Primary plasmacytoma involving mediastinal lymph nodes: a diagnostic mimicry of primary mediastinal lymphoma

Plasmacytomas could involve any organ, and at times might pose a diagnostic challenge when the site of involvement is unusual, or if the presentation is similar to other diseases. Wedescribe a 48- year-old man presenting with worsening shortness of breath and chest discomfort with radiologic evidence of mediastinal enlargement, mimicking a lymphoma with mediastinal involvement. An excisional biopsy of a mediastinal lymph node showed a plasma-cell infiltrate strongly positive for CD138, with a flow-cytometry analysis showing a population of lambda-restricted neoplastic plasma cells. He failed to respond to 50 Gy involved-field radiotherapy, but achieved a partial response to combination chemotherapy. He underwent high-dose chemotherapy with melphalan [200 mg/m[2]] followed by lenalidomide maintenance, and is in complete remission 18 months postautografting. This case illustrates a unique and rare presentation of primary lymph-node plasmacytomas involving the mediastinum potentially mistaken as lymphoid malignancy. Clinicians should be aware of the plasma-cell origin of the mediastinal neoplastic process

Clotrimazole troches induce supratherapeutic blood levels of sirolimus and tacrolimus in an allogeneic hematopoietic cell-transplant recipient resulting in acute kidney injury

Allogeneic hematopoietic cell transplantation is a potential curative treatment option for various malignant and nonmalignant hematologic disorders. Patients undergoing an allogeneic hematopoietic cell transplant are prescribed immune-suppressant therapies to facilitate hematopoietic donor-cell engraftment and prevent graft-versus-host disease. Drug-drug interactions may occur, owing to exposure to complex multidrug regimens with narrow therapeutic windows and high toxicity profiles. Here, we describe a unique case of a 65-year-old man with poor-risk acute myeloid leukemia who underwent a matched-sibling hematopoietic cell allograft. Sirolimus and tacrolimus were used for graft-versus-host disease prophylaxis. He developed oral thrush requiring treatment with clotrimazole troches, which subsequently resulted in serious renal toxicity attributed to supratherapeutic levels of sirolimus and tacrolimus. Patient renal function improved after temporarily holding both immune suppressants, and administering phenytoin to help induce sirolimus and tacrolimus metabolism. This case highlights sudden and serious toxicities that resulted from clotrimazole-sirolimus and clotrimazole-tacrolimus drug-drug interactions, even when administered topically

Role of reduced intensity conditioning in allogeneic hematopoietic cell transplantation for patients with multiple myeloma

High-dose chemotherapy followed by autologous hematopoietic cell transplantation continues to play an integral role in the treatment strategy in patients with newly diagnosed multiple myeloma. Incorporation of newer potent anti-myeloma agents has further improved outcomes. However, disease relapse or proggression remains a challenge after autologous transplantation. Allogeneic hematopoietic cell transplantattion remains the only potentially curative modality for some patients due in part to graft-versus-myeloma effect. High transplant-related mortality, in the range of 30% to 40%, previously seen with myeloablative conditioning regimens including total body irradiation plus cyclophosphamide has been significantly reduced by introducing less ablative preparative regimens, so called reduced-intensity conditioning. Cumulative evidence suggests encouraging prospects for allogeneic transplantation through improved outcomes of myeloma patients [overall survival exceeding 70% at 2 years in some studies]; however, which patient population would benefit most from this treatment remains to be defined. Newer strategies to augment graft-versus-myeloma effect and minimize post transplant toxicities are in need of further improvement in patients with myeloma