Photo Credit: Dr Microbe
The following is a summary of “Increased risk of recurrence and disease-specific death following delayed postoperative radiation for Merkel cell carcinoma,” published in the FEBRUARY 2024 issue of Dermatology by Alexander, et al.
Merkel cell carcinoma (MCC) typically undergoes treatment involving surgery and postoperative radiation therapy (PORT). However, the optimal timing for initiating PORT (Time-to-PORT [ttPORT]) remained uncertain. For a study, researchers sought to investigate whether delays in ttPORT are correlated with inferior outcomes in patients with stage I/II MCC.
Competing risk regression was employed to analyze the associations between ttPORT and locoregional recurrence (LRR) in a cohort of patients with stage I/II MCC, utilizing a prospective registry. Covariates were adjusted for, considering distant metastasis and death as competing risks.
The cohort comprised 124 patients, with a median ttPORT of 41 days (range: 8-125 days), and a median follow-up of 55 months. Among these, 17 (14%) patients experienced LRR, with 82% arising outside the radiation field. The 5-year LRR rate was higher for ttPORT >8 weeks compared to ≤ 8 weeks (28.0% vs. 9.2%, P = .006). The cumulative incidence of MCC-specific death increased with longer ttPORT (HR = 1.14 per 1-week increase, P = .016).
Delaying PORT was associated with an elevated risk of LRR, predominantly occurring beyond the radiation field. This aligns with the aggressive spread of MCC via lymphatics. Initiation of PORT within 8 weeks demonstrated improved locoregional control and MCC-specific survival.