Primary mediastinal large B-cell lymphoma: A comparative study with nodular sclerosis-type Hodgkin's disease

The clinicopathological features of 10 patients with primary mediastinal la rge B-cell lymphoma (PMLBCL) are described. The patients were aged 19 to 63 years, with a median age of 25.5 years. There were 5 men and 5 women. All patients presented with chest symptoms, and 6 presented with superior vena cava syndrome. Nine patients had bulky mediastinal tumors. The disease was confined within the thorax and contiguous lymph nodes, although multiple li ver tumors were observed in 1 patient. Laboratory findings included high la ctate dehydrogenase levels and elevated C-reactive protein levels. The solu ble interleukin 2-receptor level was high in 6 patients tested. A comparati ve study of PMLBCL and nodular sclerosis-type 1-Hodgkin's disease (NS-HD) w ith a mediastinal mass revealed substantial overlap in clinical features. H istopathological examination of biopsy specimens of PMLBCL revealed cluster s of CD20(+) large cells; however, CD30(+) Hodgkin/Reed-Sternberg-like cell s were occasionally seen, raising the potential to misdiagnose PMLBCL as NS -HD. The patients with PMLBCL were treated with CHOP (cyclophosphamide, dox orubicin, vincristine, and prednisolone), biweekly CHOP, or MACOP-B (methot rexate, doxorubicin, cyclophosphamide, vincristine, prednisolone, and bleom ycin) regimen, and 6 received consolidation radiotherapy to the involved fi eld. With the exception of 1 patient who was primarily refractory to therap y, 9 patients (90%) achieved complete response and 7 (70%) remain in contin uous remission with a mean follow-up of 24 months. (C) 2001 The Japanese So ciety of Hematology.