High rates of sentinel lymph node positivity across all age groups in Merkel cell carcinoma

Merkelcell.org Summary

Merkel cell carcinoma (MCC) is an aggressive form of skin cancer that has a high risk of spreading to nearby lymph nodes. To check if it has spread, doctors often do a sentinel lymph node biopsy (SLNB; learn more at https://www.cancer.gov/about-cancer/diagnosis-staging/staging/sentinel-node-biopsy-fact-sheet). This test removes and checks the first lymph nodes where cancer is likely to spread, to see whether MCC has spread past where it first started.
This study used a large cancer database to see if certain groups of patients, like those in a certain age range, were more or less likely to have cancer in their lymph nodes. Out of 9,687 MCC patients, 6,417 (66%) had an SLNB. Younger patients (under age 60) were more likely to get the test than older ones (over age 80). But the chance of finding cancer in the lymph nodes was similar across all age groups — about 21% in younger patients and 27% in older patients.
This means no age group had clearly different SLNB results. So, whenever possible, MCC patients of all ages should get an SLNB to help doctors decide on the best treatment to lower the chance of the cancer coming back.

Abstract

Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy, and its management often parallels guidelines for melanoma. Multiple studies in melanoma have highlighted a significant inverse relationship between increasing age and sentinel lymph node (SLN) metastasis.^1,2 Since MCC predominantly affects patients in their mid-seventies and older,³ identifying a similar relationship in MCC could aid clinical decision-making. We examined the rates of receipt of SLN biopsy (SLNB) by age and the association of age with SLN positivity in MCC using a national cohort to assess if a low-risk group could be identified in which SLNB could be safely deferred.