The study period ended in January 2005, and at that point seven of the patients had no evidence of disease after treatment, five were alive with disease, two had died from the cancer, and three were lost to follow-up.
Explore this issue:April 2006
“Of the cancer patients that we identified without the traditional risk factors for head and neck squamous cell carcinoma, the majority presented with early stage disease, yet half of them recurred or perished from their disease during our study period,” Dr. O’Leary said.
When compared to the patients with traditional risk factors in the medical literature, the non-drinking, non-smoking cohort faired worse. “They appear to have a worse prognosis, which is worrisome. Interestingly, most of these patients had more than one comorbidity,” she said.
The Role of Comorbidities
In the study, researchers investigated various comorbidities or factors that could have influenced cancer risk or outcome. In an interview with ENToday, Anand Devaiah, MD, Assistant Professor of Otolaryngology and Neurological Surgery at the University of Boston School of Medicine and the study’s lead author, said that an extensive list of additional factors were taken into account.
Patient histories were examined for a total of 15 comorbidities, 15 social exposures (such as working with toxins at work), use of immunosuppressive classes of medication, family history, and personal history of cancer.
Among the 17, three patients had diabetes, four had poor dental hygiene, four reported rare alcohol use, and two had reflux. However, the numbers are small and lack statistical power to determine causality, Dr. Devaiah said.
In the end, “we can’t conclude any one factor is causative—but this doesn’t mean it’s not a risk factor.” He noted that the patients with diabetes each had at least one other comorbidity.
“The big thing that we could pull out of the study was that 5 of the 17 people had none of the examined comorbidities. We couldn’t pull out any data that supported any significant exposure to any of those things,” Dr. Devaiah said.
Of the five who had no other apparent risk factors, two died from the cancer and one is being treated for recurrence of the disease. Only two are still alive with no evidence of the disease recurring.
Normally, patients who present with early stage disease have a significantly better cure rate. “But our patients, or this subset, had a worse outcome. The tumours seemed to be more aggressive. We certainly didn’t skimp on their treatment,” he said.