A Previously Unrecognized Granulomatous Variant of Gamma-Delta T-Cell Lymphoma.

Primary cutaneous γδ T-cell lymphoma (PCGD-TCL) is an extremely rare and aggressive T-cell neoplasm with complex heterogeneity. We present a series of two patients who presented with firm, subcutaneous nodules and were diagnosed with PCGD-TCL. In both cases, biopsies demonstrated a both superficial and deep adnexotropic infiltrate comprised of angiocentric, medium- to large-sized atypical lymphocytes. The infiltrate extended into the panniculus. Immuno-histochemical stains highlighted atypical lymphocytes that expressed CD3, CD8 and CD56 but were negative for EBV ISH. A brisk histiocytic response with focal aggregation into granulomas was highlighted with a PG-M1 stain. The atypical lymphocytes were positive for gene rearrangements on a TCR delta stain and negative for ßF-1. CT and PET scan in one of the two patients demonstrated diffuse, subcutaneous, ground-glass foci; hypermetabolic soft tissue nodules; and lymphadenopathy in the lungs, as well as splenomegaly. A diagnosis of histiocyte-rich PCGD-TCL was rendered. A histiocyte-rich, granulomatous variant of γδ T-cell lymphoma is extremely rare. Its potentially misleading resemblance to inflammatory granulomatous conditions could pose a diagnostic pitfall in this already challenging condition. This variant may resemble granulomatous mycosis fungoides and granulomatous slack skin syndrome, but it has a distinct, aggressive clinical outcome.

Primary age-related EBV-associated effusion-based lymphoma successfully treated with rituximab and thoracentesis.

EBV-positive HHV8-negative EBL is part of the spectrum of EBV-positive diffuse large B-cell lymphoma NOS. This entity can be labeled as primary age-related EBV-associated EBL and appears to respond well to rituximab and thoracentesis.

Primary peritoneal myeloid sarcoma in association with CBFB/MYH11 fusion.

Myeloid sarcoma, also known as chloroma or granulocytic sarcoma is an extramedullary disease process that typically presents in association with acute myeloid leukemia during initial presentation or at relapse. Often associated with cytogenetic mutations, including t(8;21)(q22;q22); RUNX1/RUNX1T1, and less frequently with inv(16)(p13.1q22) or t(16;16)(p13.1;q22); CBFB/MYH11, myeloid sarcoma is most commonly discovered in skin, soft tissue, bone, and connective tissue. In rare circumstances, myeloid sarcoma can present without any evidence of bone marrow or leukemic involvement. These cases of de novo myeloid sarcoma are rare, and are commonly misdiagnosed due to similarities with other entities. We report an unusual case of a primary de novo peritoneal myeloid sarcoma, in association with inv(16)(p13;q22) and clonal heterogeneity at different sites of involvement, that has responded well to AML induction therapy and consolidation treatment with gemtuzumab ozogamicin and high dose cytarabine. Cytogenetics, immunophenotyping, and chromosomal analysis, were each critical in establishing a proper diagnosis as well as helping to develop appropriate therapeutic strategies for this rare entity.

Outcomes of Hepatosplenic T-Cell Lymphoma: The Mayo Clinic Experience.

BACKGROUND: Hepatosplenic T-cell lymphoma (HSTCL) is a rare subtype of peripheral T-cell lymphoma accounting for less than 1% of non-Hodgkin lymphomas. It is generally associated with poor prognosis. PATIENTS AND METHODS: We performed a cohort study of patients with HSTCL treated at the Mayo Clinic between 1996 and 2020 exploring the clinical characteristics and therapeutic outcomes. RESULTS: Twenty-two cases of HSTCL were identified with a median (range) age at diagnosis of 45.5 (15.5-80.6) years and a male predominance (15/22, 68.2%). Clinical characteristics include massive splenomegaly in 16 patients (73%), hepatic involvement in 13 (59%), and chronic immunosuppressed state in 8 (36%). Phenotypically, lymphoma cells had gamma/delta T-cell receptor expression in 18 (82%) and alpha/beta in 4 patients. Cytogenetic abnormalities included isochromosome 7q (i7q) in 8 (62%) of 13 and trisomy 8 in 4 (44%) of 9. The median (range) follow-up of surviving patients was 33 (2.5-137) months. The median progression-free and overall survival were 9.5 months (95% CI, 1.8, 16.3) and 12.4 months (95% CI, 4.9, 18.5), respectively. Long-term survival was seen in 4 (18%) of 22 patients, with survival of 55, 74, 95, and 137 months. Moreover, 3 of 4 long-term survivors had splenectomy as part of initial treatment, and 2 of 4 long-term survivors received an allogeneic hematopoietic cell transplant (allo-HCT). CONCLUSION: Liver involvement and chronic immunosuppression were associated with shorter survival. Although splenectomy and allo-HCT have anecdotal benefit in the literature, our data do not show a statistically significant benefit of splenectomy and/or allo-HCT, likely as a result of our small sample size.

Myelodysplasia-related acute myeloid leukemia and acute promyelocytic leukemia: concomitant occurrence of two molecularly distinct diseases.

Concurrent presentation of acute promyelocytic leukemia (APL) with other hematologic diseases in the absence of previous chemotherapy or ionizing radiotherapy treatment is very rare. We present a case of simultaneous occurrence of APL with myelodysplastic syndrome (MDS)-related acute myeloid leukemia (AML). A 43-yearold female presented with 3 month of history fatigue, night sweats, chills and pancytopenia. Bone marrow aspirate and biopsy demonstrated 20% myeloid blasts with dysplastic changes admixed with abnormal promyelocytes. Cytogenetic analysis showed tetraploidy and deletion in chromosomes 5q and 7q and polymerase chain reaction showed presence of PML/RARA mRNA transcripts, confirming the presence of concurrent APL and MDS-related AML. Induction chemotherapy with cytarabine and daunorubicin was initiated along with all-trans retinoic acid. This is the first case to be reported in the literature of concurrent occurrence of APL with MDS-related AML. Treatment with 7 + 3 regimen and ATRA was successful in inducing complete remission.

Comprehensive Genomic Profiling of a Rare Thyroid Follicular Dendritic Cell Sarcoma.

We previously reported an extremely rare case of follicular dendritic cell sarcoma (FDCS) presented as a thyroid mass. Given the rarity of this disease, there are no personalized and molecularly targeted treatment options due to the lack of knowledge in the genomic makeup of the tumor. A 44-year-old white woman was diagnosed with an extranodal FDCS in thyroid. The patient underwent a total thyroidectomy, central compartment dissection, parathyroid re-implantation, and adjuvant radiation therapy. Tumor DNA sequencing of 236 genes by FoundationOne panel found truncating mutations in PTEN and missense mutations in RET and TP53. However, patient-matched germline DNA was not sequenced which is critical for identification of true somatic mutations. Furthermore, the FoundationOne panel doesn't measure genomic rearrangements which have been shown to be abundant in sarcomas and are associated with sarcoma tumorigenesis and progression. In the current study, we carried out comprehensive genomic sequencing of the tumor, adjacent normal tissues, and patient-matched blood, in an effort to understand the genomic makeup of this rare extranodal FDCS and to identify potential therapeutic targets. Eighty-one somatic point mutations were identified in tumor but not in adjacent normal tissues or blood. A clonal truncating mutation in the CLTCL1 gene, which stabilizes the mitotic spindle, was likely a driver mutation of tumorigenesis and could explain the extensive copy number aberrations (CNAs) and genomic rearrangements in the tumor including a chr15/chr17 local chromothripsis resulted in 6 expressed fusion genes. The fusion gene HDGFRP3→SHC4 led to a 200-fold increase in the expression of oncogene SHC4 which is a potential target of the commercial drug Dasatinib. Missense mutations in ATM and splice-site mutation in VEGFR1 were also detected in addition to the TP53 missense mutation reported by FoundationOne.

Mantle cell lymphoma with a novel t(11;12)(q13;p11.2): a proposed alternative mechanism of CCND1 up-regulation.

Mantle cell lymphoma (MCL) is typically characterized by t(11;14), which places the IGH@ enhancer elements upstream of CCND1. This fusion results in up-regulation of CCND1 and consequently its protein product cyclin D1. Recent studies have shown that in MCL, mutations or translocations occurring within the 3' untranslated region (UTR) of the CCND1 gene can result in a truncated mRNA transcript that is more stable and associated with more aggressive disease. We identified a case of MCL showing cyclin D1 overexpression by immunohistochemistry and a t(11;12)(q13;p11.2) by conventional cytogenetic studies. Next-generation genomic sequencing indicated a chromosomal break through the CCND1 3'-UTR and fusion with a non-coding region of chromosome 12. We suggest that, in the absence of the typical CCND1/IGH@ fusion, this rearrangement promotes MCL pathogenesis by eliminating miRNA interaction elements within the 3'-UTR of the CCND1 mRNA transcript consequently resulting in CCND1 overexpression.

Post-Transplant Lymphoproliferative Disorder Presenting as CD20-Negative Plasmablastic Lymphoma in the Lung.

Post-transplant lymphoproliferative disorders (PTLD) are a serious complication of transplantation with a high mortality. Most PTLD present within the first year of transplantation and are associated with Epstein-Barr virus (EBV) infection. Plasmablastic lymphoma (PBL) is a rare but aggressive disease originally described in patients with HIV, presenting most commonly in the jaw and oral mucosa. To our knowledge, this is the first case of PBL presenting as PTLD of the lung in a HIV and EBV negative patient. Given the increasing number of transplants performed, we would like to share this uncommon presentation of PTLD as PBL.

Hemodynamic Transesophageal Echocardiography-Guided Venous-Arterial Extracorporeal Membrane Oxygenation Support in a Case of Giant Cell Myocarditis.

Giant cell myocarditis (GCM) is a rare and commonly fatal form of fulminant myocarditis. During the acute phase, while immunosuppressive therapy is initiated, venoarterial extracorporeal membrane oxygenation (VA-ECMO) support is commonly used as a bridge to heart transplantation or recovery. Until recently, conventional transesophageal echocardiography and transthoracic echocardiography were the tools available for hemodynamic assessment of patients on this form of mechanical circulatory support. Nevertheless, both techniques have their limitations. We present a case of a 54-year-old man diagnosed with GCM requiring VA-ECMO support that was monitored under a novel miniaturized transesophageal echocardiography (hTEE) probe recently approved for 72 hours of continuous hemodynamic monitoring. Our case highlights the value of this novel, flexible, and disposable device for hemodynamic monitoring, accurate therapy guidance, and potential VA-ECMO weaning process of patients with this form of severe myocarditis.

Maxillary sinus angiomyolipoma: A case report and overview.

Otolaryngologists are called upon to evaluate and treat sinonasal masses discovered incidentally on imaging studies. Although common conditions such as sinonasal polyps and mucus retention cysts predominate, it is prudent practice to formulate a differential diagnosis to identify unusual conditions. We present a case of a maxillary sinus mass in a 78-year-old man that was discovered incidentally on brain imaging and subsequently identified on biopsy as an angiomyolipoma (AML). AMLs are benign hamartomatous tumors that rarely occur in extrarenal locations. Only a few cases have been reported in the nasal cavity. We believe our case represents the first reported instance of AML arising within a maxillary sinus. Identification of intratumoral fat within the mass on imaging studies may suggest the diagnosis of AML preoperatively. Close interdisciplinary collaboration among the otorhinolaryngology, radiology, and pathology services is beneficial for patient management. We report this case to raise awareness that AML can arise in this previously unreported location. Moreover, we wish to emphasize that AML should be considered in the differential diagnosis when imaging studies demonstrate a well-defined, heterogeneous, fat-containing solitary mass in the nasal cavity or maxillary sinus.

Excellent Outcome of Immunomodulation or Bruton's Tyrosine Kinase Inhibition in Highly Refractory Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type.

Primary cutaneous diffuse large B-cell lymphoma, leg type (PCDLBCL-LT) is a rare diffuse large B-cell lymphoma confined to the skin of the legs. The typical presentation is characterized by solitary or multiple growing plaques, usually confined to one leg. We report a case of PCDLBCL-LT of activated B-cell subtype characterized by multiple local relapses in the legs, initially, and systemic relapses about seven years after the diagnosis. Local relapses were sensitive to radiation therapy. Cutaneous and systemic relapses responded well to immunomodulatory therapy with lenalidomide followed by Bruton's tyrosine kinase inhibition with ibrutinib. Ibrutinib is the only treatment that resulted in long-lasting complete remission. Lenalidomide and especially ibrutinib appear to have a significant activity against this lymphoma and should be incorporated in the treatment of this resistant and aggressive lymphoma. To our knowledge, this is the first case of PCDLBCL-LT reported in the literature exhibiting a complete response to ibrutinib.

Intussusception of a small bowel large B-cell lymphoma.

Gastrointestinal tumors can rarely cause intestinal intussusception. Herein, we describe a 74 year-old male with a presumed diagnosis of Crohn's disease who presented with persistent symptoms refractory to medical management. Radiography demonstrated small bowel intussusception into the cecum. Lower endoscopy with biopsy diagnosed small bowel large Bcell lymphoma. Management included laparoscopic ileocecectomy and adjuvant R-CHOP chemotherapy. Long term outcomes of small bowel large B-cell lymphoma are related to disease stage at diagnosis, and average close to 75 %.

The clinical spectrum of Castleman's disease.

Castleman's disease (CD) is a rare, poorly understood lymphoproliferative disease. The spectrum of symptoms and course of disease are broad, but there is no large study describing the natural history of this disease. Basic clinic and laboratory data from the records of 113 patients with CD evaluated at the Mayo Clinic and University of Nebraska were abstracted. The impact of these variables on overall survival (OS) from time of diagnosis was evaluated. Sixty patients had multicentric disease. Of the patients with multicentric CD, 32% had criteria sufficient for a diagnosis of POEMS syndrome. For all patients, 2, 5, and 10-year OS was 92%, 76%, 59%, respectively. Most of the factors identified as risk factors for death on univariate analysis cosegregated with diagnostic criteria for POEMS syndrome, which supported the concept of four categories of CD, which are (along with their 5-year OS): (1) unicentric CD (91%); (2) multicentric CD associated with the osteosclerotic variant of POEMS syndrome (90%); (3); multicentric CD without POEMS syndrome (65%); and (4) multicentric CD with POEMS syndrome without osteosclerotic lesions (27%). We have demonstrated that CD represents a spectrum of disease that can be differentiated by simple prognostic factors that provide a framework for further study.