title: Systemic immune suppression predicts diminished Merkel cell carcinoma-specific survival independent of stage.
abstract: Merkel cell carcinoma (MCC) is an aggressive cutaneous malignancy linked to a contributory virus (Merkel cell polyomavirus). Multiple epidemiologic studies have established an increased incidence of MCC among persons with systemic immune suppression. Several forms of immune suppression are associated with increased MCC incidence, including hematologic malignancies, HIV/AIDS, and immunosuppressive medications for autoimmune disease or transplant. Indeed, immune-suppressed individuals represent ∼10% of MCC patients, a significant overrepresentation relative to the general population. We hypothesized that immune-suppressed patients may have a poorer MCC-specific prognosis and examined a cohort of 471 patients with a combined follow-up of 1,427 years (median 2.1 years). Immune-suppressed patients (n=41) demonstrated reduced MCC-specific survival (40% at 3 years) compared with patients with no known systemic immune suppression (n=430; 74% MCC-specific survival at 3 years). By competing risk regression analysis, immune suppression was a stage-independent predictor of worsened MCC-specific survival (hazard ratio 3.8, P<0.01). Thus, immune-suppressed individuals have both an increased chance of developing MCC and poorer MCC-specific survival. It may be appropriate to follow these higher-risk individuals more closely, and, when clinically feasible, there may be a benefit of diminishing iatrogenic systemic immune suppression.
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Kelly G
authors.initials: KG
authors.lastname: Paulson
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Jayasri G
authors.initials: JG
authors.lastname: Iyer
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Astrid
authors.initials: A
authors.lastname: Blom
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California, USA.
authors.forename: E Margaret
authors.initials: EM
authors.lastname: Warton
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California, USA.
authors.forename: Monica
authors.initials: M
authors.lastname: Sokil
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Lola
authors.initials: L
authors.lastname: Yelistratova
authors.affiliation: Clinical Data Systems, Fountain Valley, California, USA.
authors.forename: Louise
authors.initials: L
authors.lastname: Schuman
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA; Division of Dermatology, Department of Internal Medicine, Faculty of Medicine, Saga University, Saga, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Nagase
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA.
authors.forename: Shailender
authors.initials: S
authors.lastname: Bhatia
authors.affiliation: Division of Research, Kaiser Permanente Northern California, Oakland, California, USA.
authors.forename: Maryam M
authors.initials: MM
authors.lastname: Asgari
authors.affiliation: Divisions of Dermatology and Medical Oncology, Department of Internal Medicine, University of Washington, Seattle, Washington, USA. Electronic address: pnghiem@uw.edu.
authors.forename: Paul
authors.initials: P
authors.lastname: Nghiem
mesh_terms: D000368:Aged; D015266:Carcinoma, Merkel Cell / Q000453:epidemiology / Q000401:mortality* / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007108:Immune Tolerance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011237:Predictive Value of Tests; D011379:Prognosis; D012044:Regression Analysis; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology / Q000401:mortality* / Q000473:pathology*; D015996:Survival Rate