TY - JOUR
T1 - Regional lymph node irradiation in locally advanced Merkel cell carcinoma reduces regional and distant relapse and improves disease-specific survival
AU - Andruska, Neal
AU - Mahapatra, Lily
AU - Brenneman, Randall J.
AU - Huang, Yi
AU - Paniello, Randal C.
AU - Puram, Sidharth V.
AU - Mansour, Mena
AU - Rich, Jason T.
AU - Baumann, Brian C.
AU - Thorstad, Wade L.
AU - Daly, Mackenzie D.
N1 - Funding Information:
This work was supported in part by institutional funds from the Departments of Radiation Oncology and Pathology & Immunology , and Siteman Cancer Center at Washington University in St Louis School of Medicine .
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2021/2
Y1 - 2021/2
N2 - Background: One-third of patients with Merkel cell carcinoma (MCC) present with locally advanced disease involving the regional lymph nodes, but indications for regional lymph node radiation therapy (rLN-RT) are not well established. Materials and methods: 72 patients with locally advanced MCC were retrospectively reviewed. Regional lymph nodes were addressed with observation, lymph node dissection (LND) alone, definitive nodal radiotherapy (DnRT), or LND plus adjuvant nodal radiotherapy (AnRT). Cox regression was used to compare treatment modalities in terms of regional recurrence-free survival (RRFS), distant recurrence-free survival (DRFS), disease-free survival (DFS) and disease-specific survival (DSS). Results: rLN-RT, including both DnRT and AnRT, improved RRFS (Hazard ratio (HR): 0.07, 95% confidence interval (CI): 0.01–0.40, p = 0.003), DRFS (HR: 0.28, CI: 0.11–0.76, p = 0.01), DFS (HR: 0.23, CI: 0.09–0.58, p = 0.002), and DSS (HR: 0.23, CI: 0.06–0.90, p = 0.03). AnRT improved DFS and DSS in high-risk subgroups (e.g., extranodal extension (ENE), ≥ 2 positive lymph nodes, or bulkier lymph nodes). The benefit of AnRT increased with higher disease burden. After controlling for these adverse factors, AnRT significantly improved RRFS (HR: 0.04, CI: 0.01–0.37, p = 0.004), DRFS (HR: 0.14, CI: 0.04–0.50, p = 0.003), DFS (HR: 0.09, CI: 0.02–0.33, p < 0.001), and DSS (HR: 0.21, CI: 0.05–0.89, p = 0.03). Conclusion: rLN-RT, including both DnRT and AnRT, reduces relapse and death from MCC in patients with node-positive disease. AnRT is particularly beneficial for patients with ENE, multiple involved lymph nodes, or larger nodal foci of disease. These results argue for more liberal use of nodal RT for MCC patients who present with node-positive disease.
AB - Background: One-third of patients with Merkel cell carcinoma (MCC) present with locally advanced disease involving the regional lymph nodes, but indications for regional lymph node radiation therapy (rLN-RT) are not well established. Materials and methods: 72 patients with locally advanced MCC were retrospectively reviewed. Regional lymph nodes were addressed with observation, lymph node dissection (LND) alone, definitive nodal radiotherapy (DnRT), or LND plus adjuvant nodal radiotherapy (AnRT). Cox regression was used to compare treatment modalities in terms of regional recurrence-free survival (RRFS), distant recurrence-free survival (DRFS), disease-free survival (DFS) and disease-specific survival (DSS). Results: rLN-RT, including both DnRT and AnRT, improved RRFS (Hazard ratio (HR): 0.07, 95% confidence interval (CI): 0.01–0.40, p = 0.003), DRFS (HR: 0.28, CI: 0.11–0.76, p = 0.01), DFS (HR: 0.23, CI: 0.09–0.58, p = 0.002), and DSS (HR: 0.23, CI: 0.06–0.90, p = 0.03). AnRT improved DFS and DSS in high-risk subgroups (e.g., extranodal extension (ENE), ≥ 2 positive lymph nodes, or bulkier lymph nodes). The benefit of AnRT increased with higher disease burden. After controlling for these adverse factors, AnRT significantly improved RRFS (HR: 0.04, CI: 0.01–0.37, p = 0.004), DRFS (HR: 0.14, CI: 0.04–0.50, p = 0.003), DFS (HR: 0.09, CI: 0.02–0.33, p < 0.001), and DSS (HR: 0.21, CI: 0.05–0.89, p = 0.03). Conclusion: rLN-RT, including both DnRT and AnRT, reduces relapse and death from MCC in patients with node-positive disease. AnRT is particularly beneficial for patients with ENE, multiple involved lymph nodes, or larger nodal foci of disease. These results argue for more liberal use of nodal RT for MCC patients who present with node-positive disease.
KW - Adjuvant lymph node radiation
KW - Merkel cell carcinoma
KW - Neuroendocrine
KW - Regional lymph node radiation
KW - Skin cancer
UR - http://www.scopus.com/inward/record.url?scp=85097148757&partnerID=8YFLogxK
U2 - 10.1016/j.radonc.2020.11.003
DO - 10.1016/j.radonc.2020.11.003
M3 - Article
C2 - 33212121
AN - SCOPUS:85097148757
SN - 0167-8140
VL - 155
SP - 246
EP - 253
JO - Radiotherapy and Oncology
JF - Radiotherapy and Oncology
ER -