Are sex and gender considered in head and neck cancer clinical studies?

We analyzed the inclusion of sex and/or gender (S/G) in Head and Neck Cancer (HNC) clinical studies, through inspecting ClinicalTrials.gov (AACT) and the mention of Human Papilloma Virus (HPV) on a specific subgroup, namely oral cavity, larynx and oropharynx. Only 5% of HNC studies mention S/G as a planned analytical variable. Proportionally more observational studies treated S/G as an analytical variable than interventional studies (10% vs 5%, P-value ≤ 0.001), 8% of studies that mentioned S/G involved more than 100 subjects while 4% less than 100 (P-value ≤ 0.001). In randomized protocols, S/G was mentioned more in studies with a planned sample of more than 100 patients and including HPV status (P-value < 0.05). Small controlled studies have lower mention of S/G as an analytical variable than uncontrolled studies (4% and 10%, respectively among studies with less than 100 subjects). Significantly greater mention of S/G as an analytical variable is observed in controlled and randomized studies with a sample size greater than 100 subjects. HPV was mentioned in only 18% of oral cavity-larynx-oropharynx studies. Interventional studies do not regularly account for S/G during HNC study design. Thus, although fundamental, in studies concerning HNC the S/G variable is often not considered. In trials published in scientific journals (P-value = 0.01) and in more recent clinical trials (P-value = 0.002), S/G is taken more into account suggesting an increasing awareness on its importance. However, the need to systematically include S/G in study design clearly emerges, to better highlight sex-related differences in disease incidence and prognosis and best imbue science and medicine with the proper biological and cultural differences.

What mechanisms can't do: explanatory frameworks and the function of the p53 gene in molecular oncology.

What has been called the new mechanistic philosophy conceives of mechanisms as the main providers of biological explanation. We draw on the characterization of the p53 gene in molecular oncology, to show that explaining a biological phenomenon (cancer, in our case) implies instead a dynamic interaction between the mechanistic level-rendered at the appropriate degree of ontological resolution-and far more general explanatory tools that perform a fundamental epistemic role in the provision of biological explanations. We call such tools "explanatory frameworks". They are called frameworks to stress their higher level of generality with respect to bare mechanisms; on the other hand, they are called explanatory because, as we show in this paper, their importance in explaining biological phenomena is not secondary with respect to mechanisms. We illustrate how explanatory frameworks establish selective and local criteria of causal relevance that drive the search for, characterisation and usage of biological mechanisms. Furthermore, we show that explanatory frameworks allow for changes of scientific perspective on the causal relevance of mechanisms going beyond the account provided by the new mechanistic philosophy.

Humanised models of cancer in molecular medicine: the experimental control of disanalogy.

This paper explores the epistemology of extrapolation from model organisms to humans in molecular medicine. We take into account two common views on the issue, the homology view and the disanalogy view. In response to both interpretations, we argue that the foundational basis of extrapolations cannot simply be provided by homology and that relevant disanalogies can, thanks to the techniques of molecular biology, be experimentally controlled and exploited to allow useful and reliable extrapolations. The case of "humanised mice" in the context of cancer stem cell research provides evidence of how animal models can be construed to approximate bona fide causal analogue models of human diseases. To supplement this view we show how the epistemology of model organisms needs to take into account the engineering side of molecular medicine. Model organisms are often manipulated to create analogies or remove disanalogies with the target system. We maintain that highlighting this feature is fundamental to explain what warrants extrapolation in the search for the molecular causes of disease.

Caster Semenya: sport, categories and the creative role of ethics.

Caster Semenya, a South African 18-year-old, won the 800-metre track running title at the Berlin World Athletics Championships in 2009. Only 3 h later, her gender was being harshly contested. The investigation of the International Association of Athletics Federations (IAAF) was neither discreet nor respectful of her privacy. Caster's case has implications for the ethics of sports and debates about gender and enhancement, and for the philosophical debate about the nature of categories and the classification of people. The IAAF has not disclosed the results of their tests on Caster, and the South African Ministry of Sport has decreed that in any case she can continue running with women in her own country. But could a scientific or medical test offer uncontroversial answers regarding Caster's gender? The concept of 'gender' is partly a social construction. The authors argue that ethics may guide science and medicine at addressing such questions.