title: Absolute lymphocyte count: a potential prognostic factor for Merkel cell carcinoma.
abstract: BACKGROUND
  Absolute lymphocyte count (ALC) is a laboratory value commonly obtained during workup of patients with Merkel cell carcinoma (MCC).
  
  
  OBJECTIVE
  We report the prognostic impact of ALC as a surrogate of immune status in MCC.
  
  
  METHODS
  A complete blood cell count was available for 64 patients with MCC in the month before definitive surgery, chemotherapy, or radiation. Statistical analysis was performed with classification and regression tree analysis, log rank test, and Cox model.
  
  
  RESULTS
  Median overall survival (OS) for the cohort was 97 months. Median OS for patients with an ALC less than 1.1 k/mm(3) was 18.8 versus 110.1 months for those with ALC greater than or equal to 1.1 k/mm(3) (P = .002, hazard ratio 0.29). Multivariate analysis of OS controlling for ALC, sex, stage, adjuvant chemotherapy, hematologic malignancy, and immunosuppression demonstrated ALC as a prognostic factor (P = .03). Disease-free survival at 36 months for ALC less than 1.1 k/mm(3) was 26.9% versus 64.4% for those with ALC greater than or equal to 1.1 k/mm(3) (P = .01). ALC was not a significant predictor for disease-free survival on multivariate analysis (P = .12).
  
  
  CONCLUSIONS
  This is a single-institution retrospective data set.
  
  
  CONCLUSIONS
  ALC is associated with OS but not disease-free survival in MCC using a threshold of less than 1.1 k/mm(3). This test may provide additional prognostic information for patients with MCC.
authors.affiliation: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Johnson
authors.affiliation: Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Fang
authors.initials: F
authors.lastname: Zhu
authors.affiliation: Department of Biostatistics, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Tianyu
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Dermatopathology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Hong
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Galloway
authors.affiliation: Department of Surgical Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Farma
authors.affiliation: Department of Dermatology, Fox Chase Cancer Center, Philadelphia, Pennsylvania.
authors.forename: Clifford S
authors.initials: CS
authors.lastname: Perlis
authors.affiliation: Department of Radiation Oncology, Fox Chase Cancer Center, Philadelphia, Pennsylvania. Electronic address: aruna.turaka@fccc.edu.
authors.forename: Aruna
authors.initials: A
authors.lastname: Turaka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D015266:Carcinoma, Merkel Cell / Q000097:blood* / Q000276:immunology / Q000401:mortality* / Q000628:therapy; D015331:Cohort Studies; D003131:Combined Modality Therapy / Q000379:methods; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D018655:Lymphocyte Count; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009361:Neoplasm Invasiveness / Q000473:pathology; D009367:Neoplasm Staging; D011379:Prognosis; D016016:Proportional Hazards Models; D012044:Regression Analysis; D012189:Retrospective Studies; D018570:Risk Assessment; D012878:Skin Neoplasms / Q000097:blood* / Q000276:immunology / Q000401:mortality* / Q000628:therapy; D016019:Survival Analysis
chemical_list: D015415:Biomarkers
keywords: Merkel cell carcinoma; absolute lymphocyte count; immune function; skin cancer; skin neoplasm