Survival rates drop significantly when patients who use tobacco and are diagnosed with oral and oropharyngeal squamous cell carcinomas (OSCCs) delay treatment for more than six weeks, according to a study published on October 13 in Head & Neck.
Patients who smoked cigarettes or chewed betel quid, which is a mix of tobacco, crushed betel nut, and spices, and were diagnosed with oral cancer via visual screenings had an 18% increased risk of death if they delayed treatment more than six weeks. The survival rate was less affected in those patients who delayed treatment by more than three weeks, the authors wrote.
"Treatment delay longer than [six] weeks for OSCCs detected via a population-based screening program had unfavorable survival," wrote the group, led by Dr. William Wang-Yu Su of Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, in New Taipei City, Taiwan.
More survive but not enough
The highest numbers of OSCC cases are in areas such as South-Central and Southeast Asia and Central/Eastern Europe, where residents routinely smoke cigarettes, drink alcohol, and chew betel quid. Though the incidence worldwide has dropped over the past several decades, the overall five-year survival rate for OSCC remains, on average, about 60%. Advances in imaging, surgery, radiation, and therapies, along with collaboration among multidisciplinary teams, have improved survival rates by about 15% in the past 50 years but only 5% in the past 20 years. Because most mouth cancers are diagnosed at more aggressive stages with lower survival rates, it is imperative that clinicians develop a strategy for earlier detection and treatment.
Therefore, the researchers aimed to determine whether treatment delays can affect the survival of oral cancer patients. Using a population-based screening program in Taiwan, they observed 5,743 oral cancer patients between 2004 and 2009. Su and colleagues followed these patients through 2012 and collected data on when they received treatments and their deaths.
The numbers are clear
The hazard ratio of death from OSCC for a treatment delay of more than six weeks (compared with less than three weeks) was 1.46 (95% confidence interval [CI], 1.30‐1.65) in univariable and 1.18 (95% CI, 1.04‐1.33) in multivariable analyses, according to the authors.
Though the study highlights the importance of earlier detection and treatment, it is not without limitations. Treatment type affects survival, and the type that patients received was not available to the researchers. Information about their transitional care also was not available, the authors noted.
Knowing the risk, clinicians should prioritize treatment for these patients, they concluded.
"Unlike other prognostic factors, such as age at diagnosis, cancer stage, and cancer site that are determinants after pathologic confirmation of malignancy, the treatment delay can be shortened via arrangement of urgent treatment," the authors wrote.