Patients with head, neck cancers at greater risk for suicide
A significantly greater proportion of patients with head and neck cancer have committed suicide than the general U.S. population, according to the results of a SEER analysis.
The researchers observed the highest suicide rates among patients with cancers of the larynx and hypopharynx.
“While affective illness and alcoholism are the most important determinants of suicide in the physically healthy population, vulnerability to suicide in patients with cancer is influenced by a number of other factors, including psychosocial and psychosomatic effects of advanced illness, pain, organic mental syndromes and preexisting psychopathologic abnormalities,” Richard Chan Woo Park, MD, assistant professor of head and neck oncology and microvascular reconstructive surgery at Rutgers New Jersey Medical School, and colleagues wrote. “Despite the strong evidence of increased risk for suicide among patients diagnosed as having cancer, to our knowledge, an in-depth analysis of suicide in patients with head and neck cancer has yet to be performed.”
Thus, Park and colleagues sought to identify the incidence rate, trends and risk factors for suicide among U.S. patients with cancers of the head and neck.
The researchers accessed the 1973 to 2011 SEER database to identify 350,413 patients with head and neck cancer. Researchers calculated incidence data from the subset of the population that had a cause of death recorded as “suicide or self-inflicted injury.”
Most of the cohort were men (54%; n = 188,701) and white (82%; n = 287,899). Thirty-six percent of patients (n = 125,790) underwent surgery alone, 34% (n = 119,935) underwent surgery and radiation, and 21% (n = 74,623) received radiation alone.
The influence of demographic factors, anatomic tumor site, disease stage and time since diagnosis on the risk for suicide served as the primary endpoint.
During an observation period lasting 2,263,376 person-years, the researchers identified 857 incidences of death by suicide, with an age-, sex- and race-adjusted suicide rate of 37.9 per 100,000 person-years.
The suicide rate among patients with head and neck cancer was three times higher than that of the U.S. general population (11.8 per 100,000 person-years).
Men accounted for 88% of documented suicides (n = 757).
Patients treated with radiation alone had a higher suicide rate (standardized mortality ratio [SMR] = 5.12; 95% CI, 3.83-6.41) than patients treated with surgery alone (SMR = 2.57; 95% CI, 1.66-3.49).
Patients with cancers of the hypopharynx (SMR = 13.91; 95% CI, 11.78-16.03) and larynx (SMR = 5.48; 95% CI, 4.14-6.81) demonstrated the highest suicide risk. With the exception of patients with cancer of the thyroid gland, patients with head and neck cancer at any site had higher suicide rates than the general population.
The researchers observed the greatest risk for suicide within the first 5 years following diagnosis, with a subsequent decline over time. However, with the exception of patients with cancers of the thyroid and nasal cavity, suicide risk remained higher than the general population for up to 10 years after diagnosis.
Patients with nasopharyngeal cancer had the highest sustained risk for suicide over time, with a high SMR persisting at more than 15 to 30 years after diagnosis (SMR = 3.26; 95% CI, 2.23-4.29).
The researchers acknowledged limitations of their study, including the possibility of misclassification of cause of death.
Further, they noted that the SEER database does not collect information on rates of substance abuse, alcohol dependence or tobacco use. Since it has been established that smoking and drinking are linked to head and neck cancer — particularly cancers of the hypopharynx and larynx — increased substance abuse in this population may explain the higher incidence of suicide among patients with these cancers.
“While there is a considerable body of research that examines survival outcomes for patients with head and neck cancer, additional research and effort should also be devoted to the psychological toll that the cancer, treatments and resulting morbidity have on patients,” Park and colleagues wrote. – by Cameron Kelsall
Disclosure: The researchers report no relevant financial disclosures.