Radiation, Lymph Node Dissection, or Both: Management of Lymph Node Micrometastases from Merkel Cell Carcinoma
May 30, 2023
Annals of Surgical Oncology
May 30, 2023
These researchers used a large database to analyze the outcomes of patients who received radiation therapy (RT), lymph node surgery (CLND; ‘completion lymph node dissection’), or a combination of both (RT+CLND). They found that overall survival rates were similar among patients who received each of these three different treatments. The researchers concluded that both radiation therapy and lymph node surgery have benefits and risks, and treatment decisions should be personalized based on individual patient factors.
Background: Regional lymph node micrometastases from Merkel cell carcinoma (MCC) can be treated with completion lymph node dissection (CLND) and/or radiation therapy (RT). It is unclear how these options compare in terms of survival benefits for patients.
Patients and methods: This retrospective cohort study used data from years 2012-2019 of the National Cancer Database. Patients with MCC and clinically negative, but pathologically positive, lymph node metastases who received RT to and/or CLND of the regional lymph node basin were included. Inverse probability weight balancing was performed using covariates followed by Cox proportional hazards modeling for survival analysis.
Results: A total of 962 patients were included [median (interquartile range) age, 74 (67-80) years, 662 (68.8%) male patients, 926 (96.3%) white patients]. The majority (63%, n = 606) had a CLND only, while 18% (n = 173) had RT only, and 19% (n = 183) had both CLND and RT. From 2016 to 2019, usage of RT only increased from 10% to 31.8%. Multivariate analysis demonstrated that treatment modality was not associated with survival [RT versus CLND, hazard ratio (HR) 0.842, 95% confidence interval (CI) 0.621-1.142, p = 0.269, RT+CLND versus CLND, HR 1.029, 95% CI 0.775-1.367, p = 0.844]. This persisted after balancing weights (RT versus CLND, HR 0.837, 95% CI 0.614-1.142, p = 0.262, RT+CLND versus CLND, HR 1.085, 95% CI 0.801-1.470, p = 0.599).
Conclusions: The usage of RT for nodal micrometastasis in MCC is increasing as compared with CLND. This strategy appears to be safe, with no significant difference in survival outcomes.