Tuesday, 18 February 2014

Day 209: The icing vs. the cake

At one point during today's short cross-examination of the expert pathologist hired by JTI-Macdonald, the witness objected to being asked to comment on introductions or conclusions of scientific papers.

"The 'results' section is the important part," Dr. Barsky cautioned plaintiff lawyer, André Lespérance. "All the rest is just icing on the cake."

Icing, with its tasty but camouflaging properties, seemed a more apt metaphor for Dr. Barsky's testimony at this trial. By liberally spreading attention on the minority of lung cancers that are not associated with smoking, he seemed to cover over the layers of lung cancers that are caused by tobacco products.

André Lespérance was the only plaintiff lawyer to ask questions to Dr. Barsky. The point of his cross-examination seemed to be to get Dr. Barsky to admit to the scale of tobacco-related lung cancers and also to get him to back-track or nuance some of his views about the distinct qualities of cancers associated with other risk factors (like radon, asbestos, etc). He appeared to be much more successful in the first goal than on the second.

"The link is indisputable" - and the scale is large!

Mr. Lespérance took a poetic approach to the day -- using the scientific papers that had been included as background references on Dr. Barsky's expert opinion in order to contradict his testimony. (Dr. Barsky's report is Exhibit 40504, and the reliance documents are Exhibits 40504.1 to 40504.61).

From these, Mr. Lespérance drew a steady stream of quotable quotes about the relative importance of smoking to lung cancer: "The proportion of lung cancer attributable to cigarette smoking is greater than 90%" "The link is indisputable." "Cigarette smoking is the single most important factor in the causes of lung cancer." "Smokers are 22 times more likely to die from lung cancer than nonsmokers."

For a tobacco industry witness, Dr. Barsky seemed surprisingly ready to give his general agreement with these reflections. He accepted as a  "ball park figure" that 90% of lung cancers were caused by smoking. He comfortably volunteered that he had never doubted the the link between smoking and lung cancer, and that he was aware that the companies had taken a contrary public position. Although he has been a consultant to the companies since 1987, he had never discussed this with them, however. "It wasn’t germane to what I had been asked to do.")

A likely explanation for increased adinocarcinomas:  Light cigarettes

Mr. Lespérance was likely also pleased at Dr. Barsky's agreement that it was the way that tobacco companies changed the design of their products that was the likely increase in certain lung cancer.

He was shown a medical text book included among his references (Dail and Hammar, Exhibit 40504.21), in which it was suggested that the rise in adenocarcinoma might be attributable to "deeper and more frequent inhalation of very low tar and nicotine cigarettes" 

"I don’t think anyone knows for sure," Dr. Barsky qualified, but agreed "It is a reasonable hypothesis and as good as any to explain the shift [in type of cancer]."  

He also said he was aware that the levels of tobacco specific nitrosamines had increased in cigarettes at the same time that the tar levels had been reduced and that he thought that this too was due to  "how the cigarettes were processed."

The 10% that gets 90% of Dr. Barsky's attention

Mr. Lespérance was somewhat less successful at getting Dr. Barky to agree that the other causes of lung cancer were relatively unimportant. Nor could he getting this witness to admit that his views on lung cancers caused by radon, bronchioloalveolar carcinoma and adenocarcinoma were not mainstream scientific opinion.

There were some head-scratching moments as the lawyer contrasted Dr. Barsky's statements with seemingly contradictory statements from his own scientific authorities. How could Dr. Barsky draw the conclusion that there was a "weak to modest association" between smoking and adenocarcinoma when the article he used reflected its title: Adenocarcinoma of the Lung Is Strongly Associated with Cigarette Smoking ? (Exhibit 40504.62).

A pattern soon emerged in Dr. Barsky's asnwers. "This study is an exception to other studies. You will find that the vast majority do not support his point."  Although he claimed there were "many other" papers that supported his view, he was unable to specify any by name.

The same thing happened when he was asked to substantiate his view that bronchioloalveolar carcinoma (BAC) was not cancers resulting from tobacco use. (This exchange prompted me to Google for more information on BAC -- what I did find was an an interesting analysis of how this "weird cell carcinoma" is part of the industry's litigation strategy in the USA, and how Dr. Barsky has already been identified as part of this strategy).

Marching to his own drummer

Another area where Dr. Barsky held strong to his views in the face of contradictory evidence was on the issue of whether HPV had been established as a cause of lung cancer.

Mr. Lespérance showed him that the international cancer agency, IARC, had found in 2007 that there was inadequate evidence to draw any such conclusion. (Exhibit 1696)

Dr. Barsky predicted that IARC would change its view in future reviews, as it had previously changed its opinion on the link between HPV and cervical cancer now was. "We have to look at this as part of the historical pattern of the march of science."

Yet he did not seem to have much company on this march. Despite being given a break in which to identify other scientists supporting this view, he could offer up only one other reference (Exhibit 40504.25).

The conclusion of this report, as André Lespérance read it, sounded far from compelling: "Strictly speaking, the detection of HPV DNA alone is not sufficient to confirm an active role of the virus in this process." 

Mr. Barsky did not blink. "I have read all the articles. my position is based on the sum total of my reading. "

Later, when it was his chance to offer his witness a closing round of questions, JTI-Macdonald counsel, François Grondin, asked Dr. Barsky to describe how HPV was identified as a cause of cervical and other cancers. As he described it, this had been the accomplishment of pathologists and not epidemiology:  "Viral-induced cancers have a different line of evidence."

Epidemiology vs. Pathology

This tension between pathological evidence and epidemiological evidence seemed to underpin many of the views expressed by Dr. Barsky. and Justice Riordan focused in on this dynamic in the last questions put to this witness.

"Are any [epidemiology studies] that you have seen based on analyses of case studies when there is actually a pathological examination done on the cause of death?"

Dr. Barsky agreed that "virtually every epidemiology study makes use of pathology," but that his concerns about the need for further pathological work were not addressed by this.

Most epidemiological studies were at a time when the individual signatures of cancer types were not determined or by methods that did not allow for them to be established. "They were done in an era when there wasn’t molecular biology... There is a tobacco signature that we know about today. There is a viral signature. There is a spontaneous cancer signature. These studies will not have that information."

Well before lunch and with no further questions, Dr. Barsky was thanked for his time and offered best wishes for his return trip to Nevada.

The road ahead

With nothing scheduled after the next three sitting weeks (and with 2 of those 12 trial days sitting empty), the defence schedule is beginning to look more than a little evasive.

ITL counsel, Craig Lockwood, has the unenviable task of fielding questions on this topic, and today he was squeezed for answers. Among the questions he was more or less forced to answer this morning was whether or not Imperial Tobacco will ask for members of the two classes (i.e. Quebec smokers who are addicted or who have lung disease) to come and testify at this trial.

Mr. Lockwood said that the decision to call witnesses did not depend on how the Appeal Court would reply to their request to overturn Justice Riordan's decision that the medical records and other personal information of these individuals could not be accessed. (The Court of Appeal will hear arguments next Friday, February 28th)

He looked uncomfortable as he explained that the decision was not one that Imperial Tobacco was making independently, as the evidence from those witnesses would also affect the other defendant companies. JTI-Macdonald and Rothmans, Benson and Hedges have said they do not intend to ask for such individuals to appear.

But at the moment -- and "subject to change" -- it was still the intention for hear from these Quebecers and therefore  "our scheduling should take this into account."  

And there was more! He told Justice Riordan that "there is a good chance there will be motions that will give us guidance on the class members."

There were no further hints on what those motions might be - and Justice Riordan admitted his curiosity was piqued. "I thought I had seen every class of motion known to mankind in this trial."


Worth mentioning are some things that Dr. Barsky failed to mention. One notable absence from his testimony was any reference to lung cancers caused by second hand smoke. 

He suggested that every lung cancer among non-smokers (and even among former smokers) had a non-tobacco trigger. (The U.S. Centers for disease control estimates that about 7,000 Americans die from lung cancer caused by second-hand smoke, compared with about 127,000 from personal tobacco use.)

His response to the lack of support by any scientific authority for the idea that HPV causes lung cancer was to suggest that such organizations would soon catch up and that "science marches on." 

But he took a very different view on behalf of the tobacco companies when making a submission to the CALEPA. In that letter he cautioned the California Regulators to stick with IARC's opinion that the evidence did not yet support a link between breast cancer and passive smoking. 

Justice Riordan has previously ruled that passive smoking is not relevant to this trial, which may be why the plaintiffs did not raise this issue.

The trial did not sit this afternoon and will not sit at all tomorrow (Wednesday). On Thursday, two motions from the plaintiffs will be discussed.