Chronic idiopathic myelofibrosis terminating in extramedullary anaplastic plasmacytoma

Anaplastic extraosseous (extramedullary) plasmacytoma in the right nostril

Extraosseous (extramedullary) plasmacytomas are rare plasma cell neoplasms that can result in an erroneous and/or delayed diagnosis as often they are not considered in the differential diagnosis due to their rarity. Furthermore, the anaplastic type is one of the most difficult to recognize in biopsies. We report the case of a patient with an extraosseous plasmacytoma occluded in the right nostril. Its prompt and accurate diagnosis resulted in early treatment and a good outcome, despite the tumour being anaplastic with the risk of progressing into a plasma cell myeloma. The patient shows no recurrence or disease progression after 10 years of follow-up. Our case highlights the clinical and pathological characteristics of this rare disorder that should be considered in order to improve diagnostic criteria and thus early treatment. We also reviewed the pertinent literature.

Simultaneous and sequential concurrent myeloproliferative and lymphoproliferative neoplasms

Concurrent manifestation of two chronic-stage myeloid and lymphoid/plasmacytoid neoplasms in one patient is rare and occurs in ≤1% of patients. There has been no systematic analysis of which combinations are frequent/infrequent and whether two concurrent diseases in one patient are clonally related or represent independent diseases. We therefore characterised a series of cases from our own archive (n = 65) and collected a large number of previously reported cases of patients in whom myeloid and lymphoid/plasmacytoid neoplasms co-occurred (n = 185). The most frequent combination was Philadelphia chromosome-negative myeloproliferative neoplasm with concurrent B cell chronic lymphocytic leukaemia, accounting for approximately 50% of double-disease patients. We compared the quantity of unsorted bone marrow cell-derived JAK2(V617F) and KIT(D816V) alleles with the quantity of the lymphoid/plasmacytoid compartment and analysed a subfraction of cases with fluorescence in situ hybridisation. Although a common aberrant progenitor has been reported in some cases in the literature, we found evidence of two independent chronic-stage myeloid and lymphoid/plasmacytoid neoplasms.

Extramedullary plasmacytoma involving perirenal space accompanied by extramedullary hematopoiesis and amyloid deposition

A 62-year-old man was referred to us after unsuccessful treatment of bilateral weakness in his upper and lower extremities with paresthesia in both lower extremities. Computed tomography (CT) revealed soft tissue masses in the left kidney along the capsule and paraaortic region that were of relatively low attenuation with accompanying granular calcifications. Pathological diagnosis of the biopsy specimen was extramedullary plasmacytoma accompanied by extramedullary hematopoiesis and amyloid deposition. Although the CT findings correlated well with the pathological results, the case was extremely atypical for extramedullary plasmacytoma in respect to location and the accompaniment with extramedullary hematopoiesis.