Analysis of Prognostic Factors from 9387 Merkel Cell Carcinoma Cases Forms the Basis for the New 8th Edition AJCC Staging System
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The first consensus Merkel cell carcinoma (MCC) staging system was published in 2010. New information on the clinical course prompts review of MCC staging.
A total of 9387 MCC cases from the National Cancer Data Base Participant User File with follow-up and staging data (1998–2012) were analyzed. Prognostic differences based on clinical and pathological staging were evaluated. Survival estimates were compared by disease extent.
Sixty-five percent of cases presented with local disease, whereas 26 and 8 % presented with nodal and distant disease. Disease extent at presentation was predictive of 5-year overall survival (OS) with estimates of 51, 35, and 14 % for local, nodal, and distant disease. Tumor burden at the regional nodal basin was predictive of 5-year OS with estimates of 40 and 27 % for clinically occult and clinically detected nodal disease. For local disease, we confirm improved prognosis when the regional nodal basin was negative by pathological compared with clinical staging. We identified 336 cases with clinically detected nodal disease and unknown primary tumor and showed improved prognosis over cases presenting with concurrent primary tumor (OS estimates of 42 vs. 27 %).
Analysis of a national dataset of MCC cases validates the predictive value of disease extent at presentation. Separation of clinical and pathological stage groups and regrouping of unknown primary tumors are supported by the analysis. The revised staging system provides more accurate prognostication and has been formally accepted by the AJCC staging committee for inclusion in the 8th edition.
KeywordsSentinel Lymph Node Biopsy National Comprehensive Cancer Network Merkel Cell Carcinoma Occult Nodal Metastasis Regional Nodal Basin
MAH is supported by NIH T32CA009672-24. The data used in the study are from the NCDB PUF. The ACS-CoC has not verified and are not responsible for the analytic/statistical methodology employed or the conclusions drawn by the investigators.
KLH, MAH, TMJ, CKB, and SLW have no conflict of interest disclosures. PN is a consultant for EMD Serono; travel, accommodations, other expenses from EMD Serono; research funding from Brisol Myers Squibb to PN’s institution. AJS has research funding from MELA Sciences; AJS has stock in Merck, Amgen, Teva, and Pfizer.
- 1.Moshiri AS, Nghiem P. Milestones in the staging, classification, and biology of Merkel cell carcinoma. J Natl Compr Cancer Netw. 2014;12:1255–62.Google Scholar
- 14.Edge SBBD, Compton CC, et al. AJCC cancer staging manual, 7th edn. New York: Springer; 2010.Google Scholar
- 18.Fields RC, Busam KJ, Chou JF, et al. Five hundred patients with Merkel cell carcinoma evaluated at a single institution. Ann Surg. 2011;254:465–73; discussion 473–5.Google Scholar