This article is more than 5 years old. Information may no longer be current.

Radiation therapy may not be factor in survival of MCC patients following surgery

Patients with merkel cell carcinoma who had radiation therapy following resection had improved overall survival when compared with patients who only had surgery, but it was likely the result of factors other than radiation, according to study results.

Researchers studied 747 patients with merkel cell carcinoma (MCC) in the Surveillance, Epidemiology, and End Results (SEER) national database who underwent surgical resection (n=343; mean age, 74.9 years; 56.6% men) or surgery followed by radiation therapy (n=404; mean age, 72.2 years; 57.4% men) between 1998 and 2006. Factors associated with MCC-specific and overall survival were determined by Cox proportional regression models. Patients who had surgery and radiation were compared with those who underwent surgery alone through Kaplan-Meier survival analysis.

Patients were matched for age, sex, race or ethnicity, diagnosis period, tumor size, disease stage, primary site surgery, type of lymph node surgery and geographic region. Surviving less than 4 months and metastatic disease were exclusion criteria. MCC-specific and overall survival were associated with factors including age and disease stage.

Based on propensity scoring and matching procedure, researchers evaluated 269 pairs of patients who had surgery or who had surgery plus radiation therapy. Patients with radiation therapy plus surgery had improved overall survival (P=.03) but not MCC-specific survival (P=.26).

“The results of the present study indicate that, although SEER patients who received radiation therapy following resected MCC demonstrated an increased overall survival compared with patients who received surgery alone, the hazard of death from MCC is not significantly associated with radiation therapy,” the researchers reported. “The lack of improvement in MCC-specific survival brings into question the therapeutic value of radiation therapy for these patients.”

Disclosure: The researchers declare no relevant financial disclosures.