title: Mediastinal large B-cell lymphoma: clinical and immunohistological findings in 18 patients treated with different third-generation regimens.
abstract: We report on the immunophenotype, clinical findings and response to aggressive chemotherapy of 18 patients with mediastinal large B-cell lymphoma (MLCL). Cases were collected from a series of 286 high-grade non-Hodgkin's lymphomas (HG-NHL) which, in the period September 1988 to August 1991, were enrolled in a prospective multicentre trial designed to compare the MACOP-B and F-MACHOP regimens. Immunostaining on frozen sections revealed a previously unrecognized phenotype, i.e. co-expression of B-cell (CD19, CD20, CD22, Ig-associated dimer) and activation-associated antigens (CD30 and CDw70) in about 60% of MLCL cases; in contrast, the activation-associated antigens CD25 and Ki-27 (unclustered) were consistently negative. This peculiar phenotype may reflect a derivation of the tumour from a subset of thymic activated B cells. Clinically, the patients (median age 31 years; F/M ratio 2.6) presented with bulky mediastinal mass (72%) associated with mediastinal syndrome in > 50% cases; disease was stage IIA in most cases. All 18 patients received aggressive chemotherapy (F-MACHOP 11; MACOP-B 7). Complete response (CR) was achieved in 57.1% of cases treated with MACOP-B. In contrast, the response of the 11 MLCL treated with F-MACHOP was poor (CR 18.2%) as compared to that of the 135 HG-NHL treated with the same regimen during the trial (CR 69.6%). This difference was still statistically significant after adjusting for negative prognostic factors (mediastinal mass > 10 cm plus increased LDH) and suggests that F-MACHOP might not be the most appropriate regimen for this kind of lymphoma.
authors.affiliation: Institute of Haematology, University of Perugia, Italy.
authors.forename: B
authors.initials: B
authors.lastname: Falini
authors.forename: S
authors.initials: S
authors.lastname: Venturi
authors.forename: M
authors.initials: M
authors.lastname: Martélli
authors.forename: A
authors.initials: A
authors.lastname: Santucci
authors.forename: S
authors.initials: S
authors.lastname: Pileri
authors.forename: E
authors.initials: E
authors.lastname: Pescarmona
authors.forename: M
authors.initials: M
authors.lastname: Giovannini
authors.forename: P
authors.initials: P
authors.lastname: Mazza
authors.forename: M F
authors.initials: MF
authors.lastname: Martelli
authors.forename: L
authors.initials: L
authors.lastname: Pasqualucci
mesh_terms: D000293:Adolescent; D000328:Adult; D000971:Antineoplastic Combined Chemotherapy Protocols; D001761:Bleomycin / Q000627:therapeutic use; D003520:Cyclophosphamide / Q000627:therapeutic use; D003561:Cytarabine / Q000627:therapeutic use; D004317:Doxorubicin / Q000627:therapeutic use; D006801:Humans; D007150:Immunohistochemistry; D016393:Lymphoma, B-Cell / Q000188:drug therapy* / Q000473:pathology; D008479:Mediastinal Neoplasms / Q000188:drug therapy* / Q000473:pathology; D008727:Methotrexate / Q000627:therapeutic use; D008875:Middle Aged; D011239:Prednisolone / Q000627:therapeutic use; D016019:Survival Analysis; D016896:Treatment Outcome; D014750:Vincristine / Q000627:therapeutic use
chemical_list: D003561:Cytarabine; D001761:Bleomycin; D014750:Vincristine; D004317:Doxorubicin; D003520:Cyclophosphamide; D011239:Prednisolone; D008727:Methotrexate