City of Salem v. Stadeli

396

Argued and submitted April 20, affirmed August 9, 2023

In the Matter of the Compensation of

Maurice Stadeli, DCD, Claimant.

CITY OF SALEM,

Petitioner,

v.

Maurice STADELI, Deceased,

Respondent.

Workers’ Compensation Board

2000008; A177746

535 P3d 329

Employer seeks review of a Workers’ Compensation Board order that set

aside its denial of claimant’s occupational disease claim for tonsillar cancer.

Specifically, the board concluded that employer had not rebutted the “firefighters’

presumption” under ORS 656.802(5), which required employer to establish by

clear and convincing medical evidence that claimant’s cancer was not caused or

contributed to in material part by his employment. Held: The board did not err

as a matter of law in construing the standard to rebut the firefighters’ presump-

tion in ORS 656.802(5)(b). Rebutting the firefighter’s presumption under ORS

656.802(5)(a) requires clear and convincing medical evidence that the firefighter

claimant’s employment was not a fact of consequence of any amount in causing

or contributing to the claimant’s condition or impairment. The board also did not

err in finding that the record did not meet employer’s burden of persuasion under

that standard.

Affirmed.

Rebecca A. Watkins argued the cause for petitioner. Also

on the briefs were Jaime M. Carlton and SBH Legal.

Nelson Robert Hall argued the cause for respondent. Also

on the brief was Bennett Hartman, LLP.

Before Aoyagi, Presiding Judge, and Joyce, Judge, and

Jacquot, Judge.

JOYCE, J.

Affirmed.

Cite as 327 Or App 396 (2023) 397

JOYCE, J.

After working as a firefighter paramedic for employer

City of Salem for many years, claimant Maurice Stadeli

was diagnosed with tonsillar cancer. He underwent treat-

ment but died about six months later. This case requires

us to assess whether the Workers’ Compensation Board

(“board”) properly construed and permissibly applied the

so-called “firefighters’ presumption” when it reversed

employer’s denial of claimant’s occupational disease claim.

Under that presumption, when a firefighter contracts a

specified disease, including cancer of the throat and mouth

(and meets other criteria, undisputed here), the firefighter

need not satisfy the usual occupational disease standard:

that work was the major contributing cause of the disease.

ORS 656.802(2)(a). Instead, the disease is an occupational

disease presumed to be caused by the firefighter’s employ-

ment. ORS 656.802(4), (5). As applicable here, the employer

may rebut the presumption—and may deny a claim for a

condition or health impairment caused by the disease—

only “on the basis of clear and convincing medical evidence

that the condition or impairment was not caused or contrib-

uted to in material part by the firefighter’s employment.”

ORS 656.802(5)(b).1

We state the facts supported by substantial evi-

dence consistently with the board’s order. ORS 656.298(7);

ORS 183.482(8)(c). Claimant worked as a firefighter for over

25 years. He also chewed tobacco for “many years.” In 2018,

a biopsy of claimant’s right tonsil revealed an invasive squa-

mous cell carcinoma that was positive for the human papil-

lomavirus 16 (HPV-16).

All four physician experts who offered evidence in

this case agreed that HPV is a cause of tonsillar cancer

generally, and all three who evaluated claimant’s situation

agreed that HPV was a probable cause of claimant’s cancer

specifically. The three experts on whom the board relied in

reaching its decision—Drs. Pierce, Orwoll, and Beer—also

1

As we discuss below, 327 Or App at 405-07, a slightly different standard

applies to employers attempting to rebut the presumption for another group of

diseases. ORS 656.802(4)(a).

398 City of Salem v. Stadeli

agreed that HPV was the most significant probable cause of

claimant’s cancer.

Those experts were also asked about the probability

that either claimant’s habit of chewing tobacco or his work

as a firefighter were causally connected to his cancer. As to

both, no expert was able to cite studies in medical litera-

ture supporting a connection between either tobacco or fire-

fighting and tonsillar cancer, but neither were they able to

definitively state that either had no connection to claimant’s

cancer.

Pierce, Orwoll, and Beer all had varying opinions

regarding whether tobacco contributed to claimant’s cancer:

(1) Pierce viewed it as a “probable” or “possibly minor” cause.

Although he admitted that the medical literature tended to

support a connection only to front-of-mouth cancers, none-

theless “it’s not good to have carcinogens in your mouth.

You’re going to swallow them past your base of tongue and

tonsil.” (2) Orwoll could not “disagree that [claimant’s] use

of smokeless tobacco might have contributed to his cancer[.]”

She found “ample” data to connect smoking and non-HPV

oropharyngeal cancer, as well as data connecting snuff with

head and neck cancer. “Data in reference to chewing tobacco

for a posterior pharynx cancer are not readily available. I

have been able to determine nothing which would suggest

that there was a significant causal relationship in this

claimant’s case.” (3) Beer concluded that “tobacco use [was]

not a clear contributor in [claimant’s] case.” He noted:

“Tobacco use is a well-recognized risk factor for oropharyn-

geal cancer in general. The strongest and most extensive

evidence supports a strong relationship between smoking

and oropharyngeal cancer. The risk for smokers is as high

as 10-fold higher than in non-smokers. The data for chew-

ing tobacco is less extensive. Chewing tobacco is a risk fac-

tor for oral cancers overall, but most of the impact appears

to be on cancers of the front of the mouth (lips, che[e]ks, and

gums). The impact of chewing tobacco products on tonsillar

cancer is not as well established and is certainly smaller

than smoking.”

Pierce, Orwoll, and Beer also had slightly vary-

ing opinions regarding whether firefighting contributed to

Cite as 327 Or App 396 (2023) 399

claimant’s cancer: (1) Although Pierce acknowledged that

firefighting “can’t be excluded” as contributing to claim-

ant’s cancer, “the way we understand it[,] it’s not thought

to” materially contribute. He noted that a number of stud-

ies show correlations between carcinogen exposure that can

occur with firefighting and “certain types of cancer”—such

as lymphoma, mesothelioma, and kidney cancer, as well as

“laryngeal cancers but not other head and neck cancers”—

but no study addressed tonsillar cancer: “[I]t’s really hard

to find anything specific on tonsillar cancer in firefighting.

I couldn’t find it, actually.” When asked whether certain

“known or probable human carcinogens” to which firefight-

ers are exposed play a “contributing role” in tonsillar can-

cer, Pierce responded: “Any known human carcinogen would

have the potential to contribute to any individual’s develop-

ment of cancer. * * * [C]ertainly no one would argue that any

of the known carcinogens couldn’t contribute to the develop-

ment of cancer.”

(2) Orwoll believed that it was “extremely unlikely

that [claimant’s] occupational exposure materially contrib-

uted to cause his cancer.” Similar to Pierce, Orwoll acknowl-

edged that “[o]ne could certainly never say that there is

absolutely no chance that any [of claimant’s firefighting

activities] could have any effect whatsoever on cancer devel-

opment.” In Orwoll’s view, the medical literature shows

“inconsistent and inconstant association” between firefight-

ing and all types of head and neck cancer, and found “no

reliable medical evidence that paramedic/firefighting activ-

ities create an elevated risk for tonsillar cancer[.]”

(3) Beer concluded that, “to a reasonable degree

of medical probability, [claimant’s] work as a paramedic/

firefighter was not a fact of consequence in causing or con-

tributing to his cancer.” Like Pierce and Orwoll, in the con-

text of his opinion regarding the lack of connection between

firefighting and tonsillar cancer, Beer acknowledged that

“it is never possible in medicine to reach 100% confidence

with regard to causation of cancer” and admitted that “no

specific test or marker * * * can prove that [claimant’s] work

as a firefighter didn’t contribute to his tonsillar cancer in

some minor way.” However, Beer observed that “[n]umer-

ous studies have examined potential relationships between

400 City of Salem v. Stadeli

firefighting and cancer risk.” Existing research inconclu-

sively “posits that firefighters may have an increased risk

of certain types of cancer due to carcinogen exposure” but

that research “does not demonstrate an increase in risk of

oropharyngeal cancer or specifically tonsillar cancer among

firefighters.”

Notably, the experts differed in their opinions about

whether HPV alone caused claimant’s cancer. Pierce main-

tained that HPV alone was insufficient, identified tobacco

as the most likely cofactor in claimant’s case, but admitted

that anything else could be a cofactor. By contrast, Orwoll

and Beer were of the view that HPV was the sole cause of

claimant’s cancer.

As noted above, in Pierce’s opinion, claimant’s can-

cer was likely caused by HPV and tobacco use. He further

opined that HPV alone was insufficient to cause tonsillar

cancer. He specifically explained that HPV infection is com-

mon, while throat cancer is not. “HPV is a very important

[factor in tonsillar cancer], but there are other factors, cer-

tainly.” Given the state of current medical science, Pierce

indicated that it is (1) uncertain or “all to be worked out”

what those other factors are, which could include other car-

cinogens or the biology of the host, and (2) impossible to

exclude anything as a possible contributing cause:

“we know that having HPV increases your risk of getting

tonsillar or base of tongue cancer by 1,400 percent. But for

a given patient sitting in front of us, with all their genetics

and individual exposures, there’s no way for us to exclude

anything, to be honest. Nothing. No way ever.”

Orwoll concluded that claimant’s cancer “was caused

by the HPV virus * * *, which is known to be the cause of

this sort of cancer.” Her opinions reiterate several times that

HPV was “the” cause of claimant’s cancer. Orwoll was not

asked about, nor did she address, Pierce’s theory that the

low rate of tonsillar cancer among the HPV-infected implies

that other cofactors must be at play.

In his initial opinion, Beer stated that HPV “alone

was the most likely cause.” When Beer was asked to respond

to Pierce’s testimony that “medical science is incapable of

excluding all possible causes of cancer, particularly in the

Cite as 327 Or App 396 (2023) 401

case of an individual patient,” Beer agreed with Pierce’s

statement. As to the point that few HPV infected people

develop cancer, Beer agreed:

“Claimant’s counsel has tried to minimize the

likely impact of HPV, pointing out that not everyone who

has HPV goes on to develop cancer. It is true that not

everyone who has HPV will develop cancer. Likewise, not

everyone who smokes develops lung cancer; not every life-

guard unwilling to lather themselves in sunscreen will

develop skin cancer; nor will every person who has worked

with asbestos develop mesothelioma. However, scientific

research informs that tobacco use does cause lung, mouth

and throat cancer; sun exposure does cause skin cancer;

and exposure to certain chemicals, like asbestos does cause

mesothelioma. The same is true of HPV and weighing the

totality of the facts, it is the most probable explanation for

[claimant’s] cancer.”

Beer stood by his view that claimant’s “cancer likely resulted

from his underlying HPV.”

A fourth physician, Holland, also provided evidence,

which we summarize separately because the board did not

rely on it. Unlike the other experts, Holland did not exam-

ine claimant or his records. His evidence consisted of an

opinion he had provided regarding another firefighter, Matt

Laas, who also contracted tonsillar cancer, and a letter in

which he agreed that his analysis, opinions, and conclusions

in the Lass matter also applied to claimant’s matter. Like

the other physicians, Holland agreed that tonsillar cancer

is associated with HPV; he opined that HPV had “played

a causative role in the development of Mr. Laas’ tonsil can-

cer.” In Holland’s view, “[o]ther carcinogens almost certainly

play a role in the development of HPV-associated squamous

cell carcinoma.” In particular, he cited studies supporting

a causal connection between smoking and the development

of cancer in HPV-positive individuals. As to firefighting,

Holland stated:

“I am not an expert on the carcinogens that fire-

fighters are exposed to in their work. Still, ORS 656.802

acknowledges that firefighters with at least five years

employment have an increased risk of cancer of the throat.

402 City of Salem v. Stadeli

Just as tobacco smoke has been shown to play a role in

the carcinogenesis of a distinct form of HPV-associated

oropharyngeal cancer, I believe that the carcinogens that

Mr. Laas has been exposed to as a firefighter likely played

a role in the development of his tonsil cancer.”

The administrative law judge (ALJ) weighed all the

evidence, including the opinions of all four physicians, and

the presumption itself, and found that the evidence “pre-

ponderates in the employer’s favor because there is clear

and convincing medical evidence from Drs. Beer, Orwoll,

and Pierce that claimant’s squamous cell carcinoma of

the right tonsil was not caused or contributed to in mate-

rial part by claimant’s employment.” Accordingly, the ALJ

upheld employer’s denial of claimant’s occupational disease

claim.

On review, the board reversed the ALJ’s order and

set aside employer’s denial of claimant’s occupational dis-

ease claim. As explained in more detail below, the board was

“not persuaded that [the opinions of Drs. Pierce, Orwoll, and

Beer] establish by clear and convincing medical evidence

that the decedent’s cancer was not caused or contributed to

in material part by his employment.”

On judicial review, the parties’ arguments center on

whether the board permissibly determined that employer had

not rebutted the presumption. Although the parties and the

board generally agreed about the standard the board should

apply in evaluating whether employers have rebutted the

firefighters’ presumption, construing ORS 656.802(5)(b)—

the standard for rebutting the presumption that applies

here—is an issue of first impression. For that reason, we

address the parameters of the standard before turning to

the board’s decision.

I. THE APPLICABLE STANDARD

We first consider whether the board correctly con-

strued the standard for rebutting the firefighters’ pre-

sumption in ORS 656.802(5)(b). We review the board’s

interpretation of statutes for errors of law. ORS 656.298(7);

ORS 183.482(8)(a).

Cite as 327 Or App 396 (2023) 403

The firefighters’ presumption is set out in two sub-

sections of the occupational disease statute, ORS 656.802(4)

and (5).2 The subsections share certain similarities: they

afford the firefighters’ presumption (1) to firefighters with

five or more years of employment (2) when death, disability, or

impairment is from a specified disease. Neither of those two

facets of the statutory scheme is disputed in this case. The

subsections differ in several ways, two of which are germane

to our analysis: the specified diseases and the standards for

rebutting the presumption. We briefly describe the two sub-

sections, highlighting those two differences.

ORS 656.802(4), enacted in 1961, specifies “any

disease of the lungs or respiratory tract, hypertension or

cardiovascular-renal disease.” Or Laws 1961, ch 583, § 1.

As the Supreme Court has observed, “[p]roponents of the

2

ORS 656.802 provides, in part:

“(4)(a) Death, disability or impairment of health of firefighters of any

political division who have completed five or more years of employment as

firefighters, caused by any disease of the lungs or respiratory tract, hyperten-

sion or cardiovascular-renal disease, and resulting from their employment

as firefighters is an ‘occupational disease.’ Any condition or impairment of

health arising under this subsection shall be presumed to result from a fire-

fighter’s employment. However, any such firefighter must have taken a phys-

ical examination upon becoming a firefighter, or subsequently thereto, which

failed to reveal any evidence of such condition or impairment of health which

preexisted employment. Denial of a claim for any condition or impairment

of health arising under this subsection must be on the basis of clear and

convincing medical evidence that the cause of the condition or impairment is

unrelated to the firefighter’s employment.

“* * * * *

“(5)(a) Death, disability or impairment of health of a nonvolunteer fire-

fighter employed by a political division or subdivision who has completed five

or more years of employment as a nonvolunteer firefighter is an occupational

disease if the death, disability or impairment of health:

“(A) Is caused by brain cancer, colon cancer, stomach cancer, testicular

cancer, prostate cancer, multiple myeloma, non-Hodgkin’s lymphoma, cancer

of the throat or mouth, rectal cancer, breast cancer [or] leukemia * * *;

“(B) Results from the firefighter’s employment as a nonvolunteer fire-

fighter; and

“(C) Is first diagnosed by a physician after July 1, 2009.

“(b) Any condition or impairment of health arising under this subsection

is presumed to result from the firefighter’s employment. Denial of a claim for

any condition or impairment of health arising under this subsection must

be on the basis of clear and convincing medical evidence that the condition

or impairment was not caused or contributed to in material part by the fire-

fighter’s employment.”

404 City of Salem v. Stadeli

bill explained that, according to statistical studies, fire-

fighters are more likely than other occupations to develop

heart and lung diseases, due to smoke and gas exposure in

strenuous conditions, and that firefighters should not bear

the burden of demonstrating that a disease or condition

was caused by firefighting.” SAIF v. Thompson, 360 Or 155,

158, 379 P3d 494 (2016) (citing Minutes, Senate Labor and

Industries Committee, HB 1018, Mar 8, 1961). Although

the presumption was always “disputable,” the legislature

amended the provision several times to clarify the scope of

both the presumption and the standard for rebutting it. See

Thompson, 360 Or at 158-60. Under the current version of

ORS 656.802(4):

“if the claimant prove[s] certain predicate facts, it [is] pre-

sumed that the claimant’s condition resulted from * * *

employment as a firefighter. Employers [may] deny a claim

only ‘on the basis of clear and convincing medical evidence

that the cause of the condition or impairment is unrelated to

the firefighter’s employment.’ ”

Thompson, 360 Or at 160 (emphasis added; citation and

some internal punctuation omitted).

ORS 656.802(5), enacted in 2009, specifies a differ-

ent, longer list of diseases and, as pertinent here, includes

“cancer of the throat or mouth.” Or Laws 2009, ch 24, § 1;

ORS 656.802(5)(a)(A). The standard for rebutting the fire-

fighter’s presumption is also worded slightly differently:

“Denial of a claim for any condition or impairment of

health arising under this subsection must be on the basis

of clear and convincing medical evidence that the condition

or impairment was not caused or contributed to in material

part by the firefighter’s employment.”

ORS 656.802(5)(b) (emphasis added).

The board and the parties concur that the phrase

“in material part” in ORS 656.802(5)(b) should have the

same meaning as the identical phrase in ORS 656.245(1)(a).3

3

ORS 656.245(1)(a) provides:

“For every compensable injury, the insurer or the self-insured employer

shall cause to be provided medical services for conditions caused in material

part by the injury for such period as the nature of the injury or the process

of the recovery requires, subject to the limitations in ORS 656.225, including

Cite as 327 Or App 396 (2023) 405

In Mize v. Comcast Corp-AT & T Broadband, 208 Or App

563, 569-70, 145 P3d 315 (2006), we concluded that “the

words ‘in material part’ [in ORS 656.245(1)(a)] refer to a fact

of ‘consequence’ ” and explained that “any contribution by a

work-related injury to a claimant’s current condition could

be a ‘material’ factor * * * without regard to the amount of

its contribution so long as the injury is a fact of consequence

regarding the claimant’s condition.” (Emphasis in original;

footnote omitted). We applied standard methods of statutory

construction to reach that construction. Nothing we con-

sulted in that interpretational endeavor has since changed:

the statutory and dictionary definitions remain the same,

as do the related statutes within ORS chapter 656. See id.

at 569-70. Notably, in Mize, we were construing a phrase

within the same statutory scheme as the statute at issue

here. And, as we noted in Mize, “[i]f the same term is used

throughout a statutory scheme, it is presumed that the leg-

islature intended the term to have the same meaning.” Id.

at 569.

We perceive no reason to construe “in material

part” differently now in ORS 656.802(5)(b) than we did in

Mize in ORS 656.245(1)(a). Therefore, in ORS 656.802(5)(b),

“in material part” refers to a fact of consequence, without

regard to the amount of causation or contribution beyond

being a fact of consequence. For that reason, rebutting the

firefighter’s presumption under ORS 656.802(5)(a) requires

clear and convincing medical evidence that the firefighter’s

employment was not a fact of consequence of any amount in

causing or contributing to a claimant’s condition or impair-

ment. The board correctly construed “in material part” in

ORS 656.802(5)(b) to refer to a “fact of consequence.”

II. THE BOARD’S DECISION

We next consider whether the board permissibly

applied the standard in ORS 656.802(5)(b) in deciding

that employer failed to rebut the presumption in this case.

Critically, our review of the board’s action in that regard is

such medical services as may be required after a determination of permanent

disability. In addition, for consequential and combined conditions described

in ORS 656.005(7), the insurer or the self-insured employer shall cause to be

provided only those medical services directed to medical conditions caused in

major part by the injury.”

406 City of Salem v. Stadeli

limited to assessing whether the board reasonably found, on

the evidence before it, that employer had failed to satisfy its

burden of persuasion. Thompson, 360 Or at 157-58. Because

the answer turns on our standard of review as illuminated

by the Supreme Court in Thompson in connection with the

original firefighters’ presumption provision, ORS 656.802(4),

we begin by reviewing that opinion and explaining how it

applies in this case, which involves the later-enacted ORS

656.802(5).

First, Thompson instructs that, once a claimant

establishes predicate facts, the employer must meet both

the burden of production and the burden of persuasion to

rebut the presumption. In Thompson, the Supreme Court

explained that, since the legislature added the phrase “on

the basis of clear and convincing medical evidence” to the

standard for rebutting the firefighters’ presumption in

ORS 656.802(4)(a), once a claimant proves the predicate

facts, both the burden of production and persuasion shift

to the employer. 360 Or at 160-61. ORS 656.802(5)(b) also

employs the phrase “on the basis of clear and convincing

medical evidence.” Accordingly, once claimant in this case

proved the predicate facts to support the presumption, which

no one disputes, then both the burden of production and the

burden of persuasion shifted to employer.

Second, Thompson makes clear that, even if an

employer meets its burden of production, the board may

evaluate the evidence favoring the employer and reasonably

find it lacking in persuasive value—that is, an employer may

meet its burden of production and yet fail to meet its bur-

den of persuasion. See Thompson, 360 Or at 166, 169. As we

explain below, the board in this case evaluated the evidence

favoring employer and permissibly found that employer had

not met its burden of persuasion.

In Thompson, the claimant firefighter suffered a

heart attack caused by atherosclerosis (a blocked artery due

to coronary artery disease). 360 Or at 161. It was undis-

puted, as here, that the claimant had proved the predicate

facts to give rise to the firefighters’ presumption. Id. at 157,

162. The claimant offered no medical evidence to prove that

his work caused his atherosclerosis; he relied entirely on the

Cite as 327 Or App 396 (2023) 407

firefighters’ presumption. Id. at 162. To attempt to rebut

the presumption, SAIF offered evidence from Dr. Semler,

who had examined the claimant and reviewed his medical

records. Id. at 162-64.

Responding to the ultimate question that he under-

stood that SAIF had asked him to address, Semler con-

cluded that “it is highly probable that [claimant’s] work as a

firefighter is not the major contributing cause of his cardiac

condition.” Thompson, 360 Or at 162 (brackets in original;

internal quotation marks omitted). As the Supreme Court

explained, Semler’s evidence “reduced to three propositions”:

(1) The causes of atherosclerosis are unknown; (2) the claim-

ant exhibited none of the known risk factors for atheroscle-

rosis; and (3) atherosclerosis is unrelated to firefighting (a

conclusion Semler based on the dearth of medical literature

linking firefighting to atherosclerosis). Id. at 163-64, 167-68.

In concluding that SAIF had not rebutted the pre-

sumption, the board reasoned:

“ ‘We are not persuaded * * * that Dr. Semler’s opinion

satisfies SAIF’s ‘clear and convincing’ burden to overcome

the statutory presumption. Dr. Semler conceded that the

cause of atherosclerosis is unknown. Despite that conces-

sion, Dr. Semler ruled out any contribution from claimant’s

employment as a firefighter. Dr. Semler did not persua-

sively explain, however, how he was able to make such a

categorical exclusion, given that the causes of that condi-

tion were unknown. The lack of such a persuasive explana-

tion is particularly significant, given that the record does

not establish that claimant had any identified ‘risk factors’

for atherosclerosis.’ ”

Thompson, 360 Or at 164.

On judicial review, this court reversed the board’s

order. SAIF v. Thompson, 267 Or App 356, 340 P3d 163

(2014), rev’d, 360 Or 155, 379 P3d 494 (2016). The Supreme

Court accepted review, reversed our decision, and affirmed

the board’s order. Thompson, 360 Or at 157-58.

The Supreme Court observed that the board had

done “what ORS 656.802(4) directed it to do once claimant

established, by means of the firefighters’ presumption, that

408 City of Salem v. Stadeli

his atherosclerosis ‘result[ed]’ from his employment as a fire-

fighter: The board asked whether SAIF had persuaded it by

clear and convincing medical evidence that claimant’s ath-

erosclerosis was ‘unrelated’ to his employment.” Thompson,

360 Or at 166 (brackets in original). And, in the end, “the

board reasonably could (and did) find that Semler’s report

and his testimony were not persuasive[.]” Id. at 167.

The steps the court took to reach that conclusion

inform our analysis here, and so we review each step and

apply it to this case in turn, beginning with the standard

that the experts were asked to address and moving through

the evidence the experts proffered. Our goal is to discern

whether the evidence was such that the board could rea-

sonably be unpersuaded that firefighting was not a fact of

consequence of any amount in causing or contributing to

claimant’s cancer.

To begin, we quote the board’s reasoning in this

case:

“Dr. Pierce’s opinion does not support the employer’s bur-

den. Specifically, he opined that although HPV-16 was an

important contributor to the decedent’s cancer, other con-

tributors, including firefighting, could not be ruled out. He

explained that HPV alone is not sufficient to cause cancer,

but that something in addition to HPV contributed to the

decedent’s cancer. Under such circumstances, Dr. Pierce’s

opinion does not support a conclusion, on a ‘clear and con-

vincing’ basis, that the decedent’s cancer was not caused

or contributed to in material part by his employment. See

656.802(5)(b).

“Further, we are unpersuaded by the opinions of Drs.

Orwoll and Beer. Although these physicians opined that

HPV was the most likely cause of the decedent’s cancer, they

did not persuasively explain how that conclusion ruled out

firefighting as a fact of consequence. In light of Dr. Pierce’s

opinion that something in addition to HPV contributed to

the decedent’s cancer, the opinions of Drs. Orwoll and Beer

are conclusory and not well explained.

“Moreover, Dr. Orwoll’s and Dr. Beer’s opinions are

internally inconsistent. Specifically, Dr. Orwoll stated that

the medical literature regarding firefighting and tonsillar

cancer was inconclusive; yet, she affirmatively eliminated

Cite as 327 Or App 396 (2023) 409

firefighting as a fact of consequence in the decedent’s case.

In addition, Dr. Orwoll stated that although HPV was ‘the

presumed cause’ and she did not know of any data correlat-

ing oropharynx cancer and chewing tobacco, she could not

rule out the decedent’s tobacco use as a contributing factor.

However, in contrast to her tobacco conclusion, Dr. Orwoll

eliminated firefighting as a fact of consequence based on

those very same factors (i.e., because HPV was the most

likely cause and the medical literature regarding firefight-

ing and head and neck cancer was inconclusive).

“Similarly, Dr. Beer stated that there was no test to

prove that the decedent’s employment did not contribute to

his tonsillar cancer in some minor way. Yet, he eliminated

the decedent’s firefighting as fact of consequence, which, as

set forth above, includes even a ‘minor cause.’ [S]ee Mize,

208 Or App at 571.

“Without further explanation for the foregoing inconsis-

tencies, we are unpersuaded by the opinions of Drs. Orwoll

and Beer on a ‘clear and convincing’ standard.”

(Emphasis in original; some citations omitted.)

The first proposition that the Supreme Court dis-

cussed in Thompson was Semler’s testimony that the causes

of atherosclerosis are unknown. 360 Or at 167-68. The court

observed that the board was entitled to find that that testi-

mony provided no persuasive evidence that claimant’s con-

dition was unrelated to the claimant’s employment. Id. That

kind of testimony is merely a “confession of an inability to

identify a cause” of a claimant’s condition, “rather than evi-

dence that [the] claimant’s condition or impairment is unre-

lated to” employment. Id. at 168 (brackets and emphasis in

original; internal quotation marks omitted).

Here, unlike in Thompson, all three physicians

agreed that one cause of tonsillar cancer is known: HPV

infection. Their opinions diverged, however, as to whether it

is known that HPV alone can cause tonsillar cancer. Even

assuming that both Orwoll and Beer were of the view that

HPV alone could cause tonsillar cancer, each also acknowl-

edged that other causes could not be excluded. Moreover,

Pierce testified that HPV alone was insufficient to cause

tonsillar cancer, pointing to the fact that few HPV-infected

individuals go on to develop tonsillar cancer, and that the

410 City of Salem v. Stadeli

exact nature of possible cofactors is presently unknown.

Beer responded to Pierce’s testimony by emphasizing that

HPV is definitively linked to tonsillar cancer. However clear

that link is, that clarity does not bear on whether other

causes exist. The board reasonably could have found itself

more persuaded by Pierce’s testimony that something other

than HPV is likely at play in developing tonsillar cancer,

given that the population of the HPV-infected is so much

larger than the population of those with tonsillar cancer.

And it also reasonably could have found that Beer’s remon-

strance, based only on the close connection between HPV

and tonsillar cancer, did not detract from the persuasive-

ness of Pierce’s testimony.

In Thompson, the Supreme Court next addressed

Semler’s testimony that the claimant had none of the known

risk factors for atherosclerosis. 360 Or at 168. The court

explained that that testimony only ruled out the known risk

factors, it did not bear on the possibility that the claimant’s

work was a cause of his condition, and so the board reason-

ably could have ascribed no persuasive value to that evi-

dence. Id.

Here, the evidence was unanimous that claimant

had the primary known risk factor for tonsillar cancer:

HPV. As to whether other risk factors were known, the

experts agreed that being male and over 40, claimant was

in the demographic group that is most likely to develop ton-

sillar cancer. As to tobacco use and firefighting, the experts

were generally consistent: No compelling evidence of causal

connection currently exists between either tobacco use or

firefighting and the particular kind of cancer claimant suf-

fered from; however, neither can be excluded as a possible

cause of tonsillar cancer. The board was entitled to find that

that level of uncertainty did not persuade it that claimant’s

employment was not a fact of consequence in causing or con-

tributing to his condition.4

Finally, in Thompson, the Supreme Court addressed

Semler’s opinion that the claimant’s atherosclerosis was

unrelated to firefighting, based on his inability to find in

4

See also Thompson, 360 Or at 163 n 6 (observing that the board could rea-

sonably find equivocal testimony about causation unpersuasive).

Cite as 327 Or App 396 (2023) 411

the medical literature a proven connection between fire-

fighting and atherosclerosis. Thompson, 360 Or at 168. The

board had observed that Semler had also testified that the

causes of atherosclerosis are unknown, and that the claim-

ant had no known risk factors for atherosclerosis. Id. In

light of that other testimony, the board found that the basis

for Semler’s opinion that the claimant’s atherosclerosis was

unrelated to firefighting was not apparent and accordingly

not sufficiently persuasive to meet SAIF’s burden of persua-

sion. Id. In the eyes of the Supreme Court, the board acted

permissibly:

“As we read the board’s opinion, the board evaluated the

persuasive value of Semler’s opinion and found it lacking.

As the board explained, Semler’s opinion that atherosclero-

sis is unrelated to firefighting was at odds with his testi-

mony that the causes of atherosclerosis are unknown. The

latter testimony undercut the former, or so the board rea-

sonably could find.”

Id. at 169.

Here, the experts similarly and unanimously reported

that no medical literature showed an association between

firefighting and tonsillar cancer, and that lack of empiri-

cal data led each to give the opinion that firefighting was

unlikely to have been materially related to causing or con-

tributing to claimant’s condition.

As to Pierce’s opinion, the board reasoned that it did

“not support a conclusion * * * that [claimant’s] cancer was

not caused or contributed to in material part by his employ-

ment.” To the extent that Pierce also responded that it was

“completely unknown” whether there were no other contrib-

utors other than HPV to claimant’s cancer, the board was

entitled to weigh that evidence against employer’s burden.

As to Orwoll’s and Beer’s opinions, the board

explained that they were unpersuasive for several reasons.

Again, the board was entitled to find those opinions unper-

suasive. One reason the board gave was that Orwoll and

Beer “did not persuasively explain how [the strong link

between HPV and tonsillar cancer] ruled out firefighting as

a fact of consequence.” To the extent that Orwoll and Pierce

gave opinions that firefighting was unlikely to be a fact of

412 City of Salem v. Stadeli

consequence in causing or contributing to claimant’s con-

dition, the board could reasonably see the opinions as not

establishing that it was highly probable that firefighting

was not a fact of consequence.

The board gave two other reasons for finding the

opinions of Orwoll and Beer to be unpersuasive. First, the

board observed that “[i]n light of Dr. Pierce’s opinion that

something in addition to HPV contributed to [claimant’s]

cancer, the opinions of Drs. Orwoll and Beer are conclusory

and not well explained.” On this record, the board could rea-

sonably find Pierce’s opinion more persuasive—that is, the

board could find compelling Pierce’s reasoning that it was

likely that other factors contribute to tonsillar cancer, given

that so few HPV-infected persons develop cancer—and that

Orwoll’s and Beer’s opinions did not undercut the persua-

sive value of Pierce’s opinion. But the primary reason that

the board was entitled to find persuasive the testimony of

all three of the experts is that all the opinions indicate that

the state of medical science is presently uncertain as to the

causation of tonsillar cancer, not that Orwoll and Pierce

were overly confident that science is certain in eliminating

firefighting as a cause.

For the above reasons, (1) the board did not err as

a matter of law in construing the standard to rebut the

firefighters’ presumption in ORS 656.802(5)(b), and (2) the

board permissibly could find that the record did not meet

employer’s burden of persuasion under that standard.

Affirmed.