Indolent T-lymphoblastic proliferation concomitant with acinic cell carcinoma mimicking T-lymphoblastic lymphoma: case report and literature review

Indolent T-lymphoblastic proliferation involving hepatocellular carcinoma-presentation in novel settings and comprehensive review of literature

Indolent T-lymphoblastic proliferation (iT-LBP) is a rare, non-clonal, extrathymic lymphoid proliferation with an immature T cell phenotype, indolent clinical course, and excellent prognosis. Although their pathogenesis is unclear, they are reported to be associated with Castleman disease, follicular dendritic cell tumors/sarcomas, angioimmunoblastic T cell lymphoma, hepatocellular carcinoma (HCC), myasthenia gravis, and acinic cell carcinoma. There are around 51 reported cases of iT-LBP in the literature. Recognition and accurate diagnosis of this entity is critical as it shares morphologic and immunophenotypic features with an aggressive malignancy-acute T cell leukemia/lymphoma (T-ALL). IT-LBP in HCC post-liver transplant and in metastatic sites has not been reported in the literature. Two case reports of patients presenting with recurrent and metastatic HCC in post-liver transplant settings are described. A 50-year-old man with an end-stage liver disease with HCC underwent liver transplant. A year later, he developed pulmonary metastasis with associated iT-LBP. A 69-year-old man underwent liver transplant for end-stage liver disease and HCC. Eighteen months later, he developed recurrent HCC in the transplanted liver and omental metastasis; both sites showed HCC with iT-LBP. iT-LBP in both patients expressed TdT, CD3, and CD4 and lacked CD34 and clonal T cell receptor gene rearrangements. On retrospective review, the pre-transplant HCC specimens lacked iT-LBP. We present two cases of iT-LBP associated with HCC in novel settings-in post-liver transplant patients and in recurrent/metastatic sites of HCC. In addition, a comprehensive literature review of clinical, histological, and immunophenotypic characteristics of reported cases of iT-LBP is presented.

Indolent T-lymphoblastic proliferation with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma: a case report

Objective: Indolent T-lymphoblastic proliferation (iT-LBP) is a non-neoplastic disease with an indolent clinical course, manifesting as hyperplasia of immature extrathymic T-lymphoblastic cells. Isolated iT-LBP has been observed, but the majority of iT-LBP cases has been seen in conjunction with other diseases. iT-LBP is easily misdiagnosed as T-lymphoblastic lymphoma/leukemia, and understanding the disease of indolent T-lymphoblastic proliferation may prevent misdiagnosis and missed diagnosis in pathological diagnosis. Case presentation: We report a case morphology, immunophenotypic, and molecular features of iT-LBP combined with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma and review relevant literature. Conclusion: iT-LBP combined with fibrolamellar hepatocellular carcinoma developed after colorectal adenocarcinoma is relatively rare and should always be considered as a differential diagnosis of T-lymphoblastic lymphoma and scirrhous hepatocellular carcinoma as the two disorders show highly similar clinical features.

Indolent T-lymphoblastic proliferation: A systematic review of the literature analyzing the epidemiologic, clinical, and pathologic features of 45 cases

An indolent T-lymphoblastic proliferation (iT-LBP) is a rare benign disorder characterized by an abnormal expansion of immature T-cells, which morphologically can mimic malignancy. Since the first case was described in 1999, dozens more have been reported in the literature. However, the epidemiologic, clinical, pathologic, and biologic features of this disease have not been well described. Here, we retrospectively reviewed all known cases reported in the literature to better understand this entity. A PubMed search up to January 2022 highlighted 25 papers describing cases/case series of iT-LBP, one of which was a case presentation in a slide workshop. Except for 9 of the cases in one of the papers, where it was evident that the number of CD3+/TdT+ cells were too few to conform with a diagnosis of iT-LBP, all papers and all the cases reported were included in the study amounting to a total of 45 cases. Clinicopathologic characteristics were analyzed using descriptive statistics and frequencies. Our analysis highlighted the previously known association with Castleman disease and Castleman-like features and underlined its association with dendritic cell proliferations in general, as well as uncovering high frequency of concurrence with hepatocellular carcinoma and autoimmune diseases, most notably myasthenia gravis, paraneoplastic pemphigus and paraneoplastic autoimmune multiorgan syndrome. Furthermore, the co-expression of CD4 and CD8 and high prevalence of extranodal disease and recurrences were other less well described features that were revealed.

Sirolimus for the Treatment of Airway Obstruction due to Indolent T-Lymphoblastic Proliferation

Introduction

Indolent T-lymphoblastic proliferation (iT-LBP) is a rare nonmalignant entity that presents as a proliferation of T-lymphoblasts. We report a first such case with a recurrent laryngeal obstruction presentation that was successfully controlled with Sirolimus.

Case presentation

This is the case of a 29-year-old female who presented with a recurrent significant lymphoid hyperplasia in the adenoid and tongue base region as well as a right cervical lymph node. After repeated adenoidectomies and tonsillectomies, and based on pathological and clinical findings she was diagnosed with iT-LBP. Trials of radiotherapy and immunotherapy with cyclosporine and rituximab all failed to control the progression of the disease. Sirolimus was finally able to restrict the growth and improve her symptoms.

Conclusion

While It-LBP does not usually require treatment, it is important to report cases in which treatment was crucial for the survival of the patient, and the effective role of Sirolimus in doing so, without any major adverse effects.

[Indolent T-lymphoblastic proliferation in association with localized Castleman disease: A case report]

Herein we report the case of a 41-year-old woman who presented with pelvic pain. Magnetic Resonance Imaging exhibited a single pelvic mass, measuring 50mm long axis, alongside the right iliac vessels. Histological examination of the excision specimen showed a lymphoid tumor with features of localized Castleman disease, hyaline vascular type. Moreover we identified multiple interfollicular dark clusters, composed of cells morphologically resembling cortical thymocytes. Their immunophenotype was consistent with an intermediate stage of T-cell differentiation, with the expression of CD3, CD4, CD8, TdT, CD1a, CD99, CD2, CD5, CD7 and CD10, with 40% Ki67. After integration of clinical and molecular data, the retained diagnosis was an indolent T-cell lymphoblastic proliferation associated with hyaline vascular localized Castleman disease. The clinical course confirmed the indolent nature of the proliferation, despite a late local recurrence at 7 years of the initial diagnosis, without histological modification, due to an incomplete initial resection surgery.