title: Increased risk of secondary cancers in patients with primary cutaneous T cell lymphoma.
abstract: As putative etiologic factors of primary cutaneous T cell lymphomas may have a general cancerogenic effect, we wanted to assess the risk of secondary malignancies in 319 patients diagnosed with histopathologically verified cutaneous T cell lymphomas and reported to the Finnish Cancer Registry during the years 1953-95. Standardized incidence ratios were defined as the ratio of observed to expected numbers of cases. To obtain the expected numbers of cancer, age-, sex-, and period-specific Finnish incidence rates were applied to the appropriate person-years under observation. Ninety-five percent confidence intervals were calculated assuming a Poisson distribution. For the whole period, we detected 36 secondary cancers whereas 26 were expected (standardized incidence ratios 1.4, 95% confidence intervals 1.0-1.9). The overall risk of lung cancer was significantly increased (standardized incidence ratio was 2.7, 95% confidence intervals were 1.4-4.8); and in particular small-cell lung cancer showed high standardized incidence ratios (standardized incidence ratio was 8.5, 95% confidence intervals were 2.8-20). Also, the risk of lymphomas was elevated (standardized incidence ratios for Hodgkin and non-Hodgkin lymphomas combined were 7.0, 95% confidence intervals were 1.9-18). The incidence of other cancers was similar to the national ratios. An increased risk of secondary cancers and in particular small-cell cancer of the lung and lymphomas among patients with primary cutaneous T cell lymphoma is demonstrated. In clinical practice, lung cancer and lymphomas must be kept in mind when following up patients with cutaneous T cell lymphomas.
authors.affiliation: Helsinki University Central Hospital, Department of Dermatology, Helsinki, Finland. lvakeva@helsinki.fi
authors.forename: L
authors.initials: L
authors.lastname: Väkevä
authors.forename: E
authors.initials: E
authors.lastname: Pukkala
authors.forename: A
authors.initials: A
authors.lastname: Ranki
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008175:Lung Neoplasms / Q000473:pathology; D016410:Lymphoma, T-Cell, Cutaneous / Q000175:diagnosis / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D012307:Risk Factors; D012878:Skin Neoplasms / Q000453:epidemiology* / Q000556:secondary