MATERIALS AND METHODS: We searched for FL-LP in our institution from 2000 to 2018 and characterised the neoplastic cells by flow cytometry, immunohistochemistry and fluorescence in situ hybridization. Thirteen (6.1%) of 212 FL cases were FL-LP, all de novo neoplasms. The leukaemic cells were small in 12 cases and large in one. All had concurrent FL, mostly (92%; 12/13) low-grade. The single case with large leukaemic cells had a concurrent primary splenic low-grade FL and a double-hit large B-cell lymphoma in the marrow.
RESULTS: CD10 was expressed in the leukaemic cells in 38% (5/13) cases by flow cytometry and in 77% (10/13) cases in tumours (p= 0.0471). IGH/BCL2 reciprocal translocation was identified in 85% (11/13) cases. Most patients were treated with chemotherapy. In a median follow-up time of 36 months, nine patients were in complete remission. The 2- and 5-year survival rates were at 100% and 83%, respectively. In this study, we characterised a series of de novo FL-LP in Taiwan. All patients had concurrent nodal and/or tissue tumours, which might suggest that these patients seek medical help too late.
CONCLUSION: The lower CD10 expression rate by flow cytometry than by immunohistochemistry might be due to different epitopes for these assays. Alternatively, loss of CD10 expression might play a role in the pathogenesis of leukaemic change. The clinical course of FL-LP could be aggressive, but a significant proportion of the patients obtained complete remission with chemotherapy.
MATERIALS AND METHODS: In this study we analysed the clinical and pathological features of 32 Taiwanese MDS patients with del(5q) (ie, del(5q) alone [Group A, n = 11], del(5q) with one additional cytogenetic abnormality other than monosomy 7 or del(7q) [Group B, del(5q)+1; n = 6], and del(5q) with ≥2 additional cytogenetic abnormalities [Group C, n = 15]).
RESULTS: Progression-free survival (PFS) and overall survival (OS) were more favourable for Group A than for Groups B (p < 0.05) and C (p ≤ 0.001). Multivariate analysis showed that age >70 years, thrombocytopenia, and karyotype other than del(5q) alone were poor prognostic factors. Among the patients that had World Health Organization (WHO)-defined MDS with isolated del(5q), one patient (9%) had a typical marrow morphology of 5q minus syndrome with erythroid hypoplasia and four patients (36%) had hypolobated megakaryocytes. In addition, PFS and OS were significantly more favorable for the patients with del(5q) alone than for those with del(5q)+1 (p < 0.05).
CONCLUSION: The bone marrow morphology, clinical features, and prognosis of Taiwanese MDS patients with del(5q) were different from those associated with MDS with isolated del(5q) as defined in the current WHO classification. Researchers should compare different geographic regions and racial populations to determine whether geographic and racial differences exist with respect to MDS with del(5q).