November 19, 2015 -- The suicide rate of patients with head and neck cancer (HNC) is more than three times the rate of the U.S. general population, according to a new study in JAMA Otolaryngology -- Head and Neck Cancer.
In the study, researchers from multiple departments at the Rutgers New Jersey Medical School, found that the first five years after diagnosis saw the greatest increase in suicide rates among all patients with head and neck cancer. However, while rates did decline after the first five years following diagnosis, suicide rates remained higher than that of the U.S. general population for up to 10 years, except for patients for whom cancer was found in the thyroid gland and the nasal cavity and sinuses (JAMA Otolaryngol Head Neck Surg, November 12, 2015).
The study came from the researchers wanting to understand which of these patients are most at risk, noted study author Richard Chan Woo Park, MD, of the department of otolaryngology--head and neck surgery at the medical school, in an interview with the journal.
"We all deal with patients who are very depressed and who might consider suicide. We've all had patients who have had this topic come up," he said. "I wanted to see what the true rate of suicide is as it relates to head and neck cancer and ... which patients are more at risk."
The suicide rate among the general population in the U.S. is 11.8 per 100,000 person years. While it is relatively well-known that suicide rates among cancer patients in the U.S. is higher than that of the general population, it was unknown if the suicide rates for head and neck cancer patients were similar, the authors noted.
The study included more than 350,000 cases of patients with head and neck cancer that were recorded within the Surveillance, Epidemiology, and End Results (SEER) program registry between 1973 and 2011. The subset of this population whose cause of death category was coded as "suicide and self-inflicted injury" were included in the retrospective cohort study.
Patients with cancer in the head and neck region (nasal cavity, nasal sinuses, nasopharynx, oral cavity, oropharynx, salivary glands, hypopharynx, larynx, and thyroid gland) were identified by the researchers using the SEER program, which compiles cancer incidence and survival data from multiple cancer registries throughout the U.S.
The researchers reported 857 patients whose cause of death was reported as suicide and self-inflicted injury among the 350,413 SEER registry patients with head and neck cancer. These patients were observed for a total of more than 2,260,000 person years, for an age-, sex-, and race-adjusted suicide rate of 37.9 per 100,000 person years.
According to the findings, the vast majority of those who committed suicide were men (757 of 857). Those who were identified as white also were more likely to commit suicide (793 of 857).
The cancer stage at presentation was mainly divided among 376 patients whose cancer was localized and 354 whose cancer was classified as regional, the authors reported. Rates were higher for those patients treated with radiation alone (standardized mortality ratio [SMR], 5.12; 95% confidence interval [CI], 3.83-6.41) compared with those treated with surgery alone (SMR, 2.57; 95% CI, 1.66-3.49). The highest risk was seen in those 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).
"Patients with head and neck cancer have more than three times the incidence of suicide compared with the general U.S. population," the author wrote. "Furthermore, suicide rates were highest among those with cancers of the larynx and hypopharynx."
Screening for risk groups
The authors discussed the idea that the "increased rates of tracheostomy dependence and dysphagia and/or gastrostomy tube dependence in these patients" may be factors in the increased rate of suicide observed. They also noted that psychological distress and depression are often seen in these patients.
Screening should be considered for those patients found to be in one of the increased-risk groups for suicide: those who are older, male, with cancers of the hypopharynx, or with history of radiation therapy.
The authors acknowledged several limitations with the SEER database, such as an "inherent problem" when evaluating for suicide due to possible misclassification of the cause of death. They also noted that comorbidities, including substance abuse, tobacco use, and alcohol dependence, could not be ascertained. The database does not report the use of chemotherapy, so this may be a confounder within the dataset that cannot be addressed.
"It has been well-established that smoking and drinking are linked to head and neck cancer, especially that of the larynx and hypopharynx, which may explain the increased suicide rate in this population as opposed to rates in patients with thyroid or salivary gland cancers," the authors wrote.