Transformation of double-hit follicular lymphoma to plasmablastic lymphoma: a partial role of MYC gene rearrangement.

Follicular lymphoma (FL) is genetically characterized by BCL2/IGH translocation. Some FL cases histologically transform to high-grade lymphoma, and the majority of cases transform to diffuse large B-cell lymphoma. We report herein an unusual FL case that transformed to plasmablastic lymphoma (PBL) with MYC gene rearrangement as early as 12 months after FL diagnosis. IGH/MYC translocation, the most common cytogenetic abnormality seen in de novo PBL, was also detected in the transformed tumor (double-hit lymphoma). The patient became resistant to chemotherapy and died 4 months after transformation. We speculate that the "second hit" of MYC rearrangement played a crucial role in PBL transformation (PBL-T) in this case. Highly specific three-color FISH analysis demonstrated the presence of BCL2/IGH/MYC triple fusion signals on a single chromosome as we expected, but BCL2/IGH and IGH/MYC fusion signals also coexisted in a single nucleus. The PBL-T tumor was genetically heterogeneous, despite being histologically quite homogeneous PBL. Surprisingly, three-color FISH analysis revealed that the preceding FL tumor was also genetically heterogeneous, simultaneously harboring BCL2/IGH, IGH/MYC and BCL2/IGH/MYC fusion signals (i.e. double-hit lymphoma), despite being histologically quite homogeneous FL. This suggests that MYC rearrangement played a partial role in PBL-T. Genetic instability including MYC rearrangement in the preceding FL tumor would contribute to PBL-T and poor outcome in this case. This study will broaden our understanding of the pathogenesis of high-grade transformation of FL and help improve patient outcome.

Successful treatment with biweekly CHOP for bone marrow relapse of blastic plasmacytoid dendritic cell neoplasm.

Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare and aggressive hematological malignancy derived from precursors of plasmacytoid dendritic cells. The majority of patients initially respond to multi-agent chemotherapy, though most relapse within a year and the prognosis is very poor. We report a 67-year-old man with erythema on the right chest and a nasopharyngeal mass. Histological examination revealed a mass of tumor cells expressing CD4, CD56, and CD123, but neither CD3 nor CD20. He was diagnosed with BPDCN. Bone marrow involvement was not seen at diagnosis. He achieved complete remission (CR) with CHOP-like chemotherapy. After 1 year, he relapsed with a cutaneous tumor on the head, a nasopharyngeal tumor, and massive bone marrow involvement. Relapsed BPDCN is generally resistant to chemotherapy and the prognosis is dismal. However, he was successfully treated with biweekly CHOP therapy and achieved a second CR lasting 16 months.

[Primary gastrointestinal follicular lymphoma of the small intestine with massive hemorrhage: a report of three cases].

Primary gastrointestinal follicular lymphoma (FL) has an indolent clinical presentation and many of cases are diagnosed incidentally during routine endoscopic examinations. Herein, we present 3 cases with FL of the small intestine developed massive intestinal hemorrhage that necessitated blood transfusion. In all three patients, upper and lower endoscopic examinations failed to detect the bleeding sites. Eventually, video capsule endoscopies identified ulcerative lesions in the jejunum and biopsies using single- or double-balloon endoscopy confirmed the FL diagnosis in our three cases. The respective clinical stages according to the Lugano system were I, II-1 and II-1. PET-CT did not play a significant role in identifying the gastrointestinal lesions. Two patients received rituximab monotherapy and achieved a complete response. The other remains under observation after termination of antiplatelet drug therapy. Generally, the macroscopic appearance of multiple whitish nodules and the absence of symptoms represent the typical clinical picture of gastrointestinal FL. However, this study demonstrates that patients with ulcerative lesions may be at risk for massive bleeding. Further discussion is required to determine the optimal indications for total endoscopic examination of the small intestine.

Successful treatment of histiocytic sarcoma with induction chemotherapy consisting of dose-escalated CHOP plus etoposide and upfront consolidation auto-transplantation.

Histiocytic sarcoma (HS) is an extremely rare malignant neoplasm that often exhibits an aggressive clinical presentation. In this report, we describe the case of a 38-year-old female with advanced-stage HS who was found to have a subcutaneous tumor in the left calf and enlarged lymph nodes in the left inguinal and internal iliac regions. The subcutaneous tumor and inguinal nodes were resected operatively. Immunohistochemistry of the surgical specimens showed that the malignant cells stained positive for CD163, CD68, and related markers; a diagnosis of HS was established. Following the administration of induction chemotherapy consisting of dose-escalated CHOP plus etoposide, the remaining internal iliac tumors disappeared. At that point, high-dose chemotherapy with autologous stem cell transplantation was performed as consolidation treatment. The patient remains alive with no evidence of disease for 30 months post-treatment. This report provides valuable insight into the treatment of advanced HS.

Blast phase of chronic myeloid leukemia presenting lymphoid phenotype with a chronic phase of extremely short duration.

Chronic myeloid leukemia (CML) is generally diagnosed in the chronic phase. We have recently encountered two CML-blastic phase (BP) cases, a 71-year-old woman and a 74-year-old man, who resembled de novo acute leukemia. The complete blood count was normal at least 11 and 13 months before the presentation, respectively. The leukemic cells showed predominant lymphoid phenotype. The blasts and granulocytes were positive for BCR-ABL, indicative of CML-BP. Both patients were successfully treated with prednisone and vincristine, followed by Imatinib. Our cases indicate rare presentations of CML-BP with an extremely short chronic phase. Ph-positive de novo acute leukemia should be carefully distinguished from CML-BP.

Therapy-related leukemia following chemoradiotherapy for esophageal cancer.

Chemoradiotherapy has improved the outcome of patients with esophageal cancer. Although a sufficiently long-time survival has resulted in the increase of several treatment-related late toxicities, little is still known about the incidence of secondary malignancies. In our hospital, 348 patients with esophageal cancer received chemotherapy consisting of nedaplatin and 5-fluorouracil and concurrent irradiation. Median and average follow-up durations were 8 and 21 months (1-92), respectively. Four patients developed leukemia after 19-48 months of follow-up. Two patients were diagnosed with overt leukemia from myelodysplastic syndrome presenting a complex karyotype, including the deletion of chromosome 5 or 7. Notably, one patient showed an additional chromosomal abnormality with t(9;22)(q34;q11). Other patients developed acute myeloid leukemia with t(9;22)(q34;q11) and Burkitt leukemia with t(8;14)(q24;q32). All patients eventually succumbed to leukemia. Platinum and fluorouracil have shown relatively lower risks for secondary malignancies in comparison with alkylating agents and topoisomerase II inhibitors. Especially, nedaplatin has never been described to introduce secondary neoplasms. Our report supports the idea that the concurrent administration of radiotherapy with these agents affects the risk of leukemia. Interestingly, rare balanced chromosomal abnormalities were observed in the present cases, thus providing new insights into the leukemogenesis of therapy-related leukemia.

[Prevention of hepatitis B virus reactivation in B-cell lymphoma patients receiving chemotherapy with rituximab].

Reactivation of hepatitis B virus (HBV) has been recognized as one of the most serious complications in patients receiving chemotherapy with rituximab. From October 2007 to December 2008, rituximab was administered to 123 B-cell lymphoma patients in our institute. Four patients with positive hepatitis B surface antigen (HBsAg) received preemptive entecavir, and none of them developed HBV reactivation. For 26 patients whose hepatitis B surface antibody (HBsAb) and/or hepatitis B core antibody (HBcAb) were positive, HBV-DNA was monitored for one year after completion of chemotherapy. During this period, HBV reactivation was observed in two patients. Hepatitis was prevented in one patient by the administration of entecavir at the time HBV-DNA turns positive. Another developed de novo hepatitis B due to failure of monitoring. Preemptive entecavir for HBsAg positive patients and HBV-DNA monitoring for HBsAb and/or HBcAb positive patients seem to be effective.

[Hepatic hilus extramedullary plasmacytoma diagnosed by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy in a relapsed multiple myeloma].

We report a rare case of multiple myeloma that developed extramedullary plasmacytoma at the hilus of the liver causing obstructive jaundice. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy was quite useful in the diagnosis. A 71-year-old man was diagnosed with stage IIIA multiple myeloma in June 2007 based on osteolytic lesions, increased atypical plasma cells in the bone marrow, and monoclonal (M) protein of IgA-lambda, IgG-lambda, BJP-lambda type. M-protein was decreased by MP therapy following radiotherapy for the cervical lesion. However, in February 2008, M-protein started to increase again. The patient presented with obstructive jaundice in the middle of March. Abdominal ultrasound and MRI demonstrated a 12-mm mass at the hilus of the liver and the upper biliary tract dilatation, and a stent was placed across the bile duct stricture. EUS-FNA biopsy from the hepatic hilar mass showed multiple sheets of atypical plasma cells consistent with extramedullary plasmacytoma. The abdominal and intracranial mass did not respond to bortezomib therapy and gradually developed. Radiotherapy and high dose dexamethazone therapy were performed with little effect. The patient died in June 2008. To our knowledge, this is the first reported case of extramedullary plasmacytoma diagnosed by EUS-FNA.

[Complete response achieved after rituximab plus CHOP therapy in a patient with rapidly progressing Waldenstrom's macroglobulinemia].

A 62-year-old man presented with lymphocytosis, anemia, thrombocytopenia, abdominal lymphadenopathies, and gross splenomegaly. He had a high serum immunoglobulin M (IgM) of 1,150 mg/dl and IgM-kappa type monoclonal protein was detected. Bone marrow examination demonstrated massive infiltration of CD19+CD20+CD5-CD10-CD23-lymphoplasmacytic cells, and the diagnosis of Waldenstrom's macroglobulinemia (WM) was made. The serum levels of soluble interleukin-2 receptor and beta2-microglobulin were also elevated to 14,300 U/ml and 6.2 mg/l, respectively. The high tumor burden and aggressive clinical features prompted the initiation of CHOP therapy. After three courses of CHOP, the patient recovered from anemia and the serum IgM level decreased to 615 mg/dl. Then we administered rituximab in combination with CHOP (R-CHOP therapy). After an additional five courses of R-CHOP, bone marrow tumor cells, splenomegaly and lymphadenopathies entirely disappeared and IgM-type monoclonal protein also became negative on immunofixation studies. Thus, a complete response (CR) was achieved and the patient has remained in CR for 12 months. Although new therapeutic options for WM including combination chemotherapy have recently been explored, complete response rates defined by immunofixation remain low. Our case indicates that R-CHOP therapy is fully effective and tolerable for aggressive type WM.

[Hepatitis B virus reactivation after cessation of prophylactic lamivudine therapy in B-cell lymphoma patients treated with rituximab combined CHOP therapy].

Here we report three cases of hepatitis B virus (HBV) reactivation after cessation of preemptive lamivudine therapy in B-cell lymphoma patients treated with rituximab plus CHOP (R-CHOP). Two patients received eight cycles of R-CHOP, and one received two cycles of R-CHOP followed by two courses of rituximab. As all the patients were HBV surface antigen (HBsAg) positive, lamivudine was administered simultaneously with R-CHOP to prevent virus reactivation. All the patients developed hepatitis due to HBV reactivation 6, 8 and 13 months after completion of chemotherapy, and 4, 2 and 2 months after cessation of lamivudine, respectively. They were treated with either lamivudine or entecavir and all achieved full recovery. When HBV carriers undergo immunosuppressive anticancer treatment, prophylactic antiviral therapy is well recognized as effective. However, the optimal method of prophylaxis has not yet been established. Since the introduction of rituximab, new problems such as delayed HBV reactivation from HBsAg positive patients and de novo hepatitis B from HBsAg negative patients have emerged. Guidelines for prophylactic antiviral therapy in the era of rituximab need to be established.

[Bone lesion in multiple myeloma].

Bone destruction is a hallmark of multiple myeloma(MM). Almost all MM patients develop osteolytic bone lesions that can cause pathologic fractures and severe bone pain. Osteolytic lesions result from increased bone resorption due to osteoclast stimulation and decreased bone formation due to osteoblast inhibition. Plain radiography, CT, and MRI are established imaging techniques in MM. FDG-PET imaging is promising newer scanning technique under current evaluation. The aggressive features of MM bone lesions have significantly contributed to poor prognosis. Therefore, a systemic approach to analgesia, which includes radiotherapy and orthopedic intervention, must be applied as a part of the comprehensive care plan of MM patient. Bisphosphonates have been shown to reduce vertebral fractures and bone pain.