Florid reactive lymphoid hyperplasia of the lower female genital tract (lymphoma-like lesion): a benign condition that frequently harbors clonal immunoglobulin heavy chain gene rearrangements

Non-neoplastic B-cell predominant lymphoid proliferations at the organs exposed to external environment mimicking lymphoma: A potential diagnostic pitfall

Background: Typically, lymphatic tissue proliferative lesions include either benign lesions or lymphoma. However, not all lymphatic lesions can currently be accurately classified into one category, particularly in mucosal areas that are in contact with the external environment.Aims: To explore the morphology, immunophenotype, and molecular changes of Non-neoplastic B-cell predominant lymphoid proliferations (NBPLP) in pathological areas that are exposed to external surroundings which mimicked lymphoma.Methods and Results: 18 cases of Atypical lymphoid hyperplasia (AtLP)  were retrieved in this study. The biopsy samples were mucosal samples obtained from areas exposed to external surroundings, including intestines, urethra, cervix, tonsils, and tongue. Microscopically, there is a different level of B cell hyperplasia accompanied by morphological atypia. We categorized the morphology into 4 groups: type A (7/18), type B (3/18), type C (3/18), type D (5/18). Part of the AtLP was found positive for BCR gene rearrangement (6/15), and TCR gene rearrangement (1/4). The follow-up period ranged from 14.2 to 70 months. No evidence of lymphoma was found. Therefore, we diagnosed all of the presented cases as NBPLP. We illustrated the key differential points and provided valuable diagnostic experience on each subtype.Conclusions: Areas exposed to the external environment are commonly exposed to antigen and easily present with AtLP of NBPLP, accompanying with positive IGH rearrangement. Therefore, a comprehensive evaluation of macroscopic, morphology, immunophenotype, and molecular diagnostics is required to prevent the overdiagnosis of lymphoma.

Follicle Center Lymphoma (FCL) of the Lower Female Genital Tract (LFGT): A Novel Variant of Primary Cutaneous Follicle Center Lymphoma (PCFCL)

Primary cutaneous follicle center lymphoma has been distinguished from nodal follicular lymphoma (FL) based on genomic and clinical features. The nature of other extranodal FLs is not well defined. We report 15 cases of follicle center lymphoma involving the lower female genital tract. Cases were evaluated using an immunohistochemical panel for B-cell lymphoma, B-cell clonality, fluorescence in situ hybridization for BCL2 gene rearrangement, and next-generation sequencing. All patients had localized disease with no evidence of bone marrow involvement. Most cases (12/15, 80%) had a follicular pattern, at least focally. Large centrocytes were a prominent feature leading to concern for diffuse large B-cell lymphoma by referring pathologists. Neoplastic cells were positive for CD20 and BCL-6, while BCL-2 was positive in 2/15 (13%) cases. Fluorescence in situ hybridization for BCL2 gene rearrangement was negative in 10/11 (91%) cases. Next-generation sequencing performed in 10 cases revealed TNFRSF14 as the most frequently mutated gene in 6/10 (60%) cases. No case had CREBBP or KMT2D mutations as seen in nodal FL. None of the patients had progressive disease with durable complete remission achieved in 10/12 (83%) cases. The median follow-up period was 7.8 years (range: 0.2 to 20.5 y) with a 5-year overall survival of 100%. We conclude that follicle center lymphoma of the lower female genital tract is a novel variant of primary cutaneous follicle center lymphoma. Despite a frequent component of large cells, it is characterized by localized disease and low risk for dissemination. Awareness and recognition are important to distinguish these lesions from aggressive B-cell lymphomas.

Florid Lymphoid Hyperplasia or Lymphoma-like Lesion of the Lower Genital Tract: A 35-Year Literature Review in View of the New WHO Classification

Florid lymphoid hyperplasias of the lower female genital tract, also known as pseudolymphoma or lymphoma-like lesions, are benign lesions displaying histologic features which mimic aggressive B-cell lymphomas. Initially described by Young and colleagues in 1985, fewer than 100 cases have been published, making this lesion rather uncommon and subject to misdiagnoses. However, given that this entity has now been included in the World Health Organization's most recent classification, greater clarity would be beneficial for pathologists and physicians. Thus, our report aims to review these entities and provide all available data. We reviewed the available literature according to PRISMA guidelines. We found that lymphoma-like lesions, regardless of their localization, display numerous superficial lymphoid B cells admixed with a polymorphic small lymphocytic and plasmocytic background and, sometimes, superficial ulceration. Large lymphoid cells show prominent nucleoli and mitotic figures. Immunohistochemistry can usually exclude large cell lymphomas, such as high-grade follicular lymphoma and Burkitt lymphoma, when a starry sky pattern is found, as well as Hodgkin Lymphoma; however, the exclusion of diffuse large B-cell lymphoma or marginal zone lymphoma is more difficult. Explorations seeking infectious agents may show Epstein-Barr virus or, rarely, Borrelia burgdorferi involvement. Molecular study occasionally finds a monoclonal B-cell population, but without the subsequent follow-up which would otherwise be worrisome. Despite its somewhat aggressive histologic features, the benignity of this entity must be highlighted to avoid misdiagnosis and complications due to overtreating.

Expressions of the CagA protein and CagA-signaling molecules predict Helicobacter pylori dependence of early-stage gastric DLBCL

Expression of CagA and CagA-signaling molecules p-SHP2 and p-ERK is associated with HP dependence of gastric DLBCL. CagA is associated with the direct lymphomagenic effect of HP on B cells of HP-dependent gastric DLBCL.

Primary diffuse large B cell lymphoma arising from a leiomyoma of the uterine corpus

Background

Primary diffuse large B cell lymphoma (DLBCL) of the uterus is rare, and primary DLBCL arising from a uterine leiomyoma (collision tumor) has not been reported in the literature.

Case presentation

We describe the clinical, histological, immunohistochemical, and molecular features of primary DLBCL arising from a leiomyoma in the uterine corpus. A 73-year-old female patient had a uterine mass for 23 years. An ultrasound scan revealed marked enlargement of the uterus, measuring 18.2 × 13 × 16.3 cm, with a 17.6 × 10.9 × 11.6 cm hypoechoic mass in the uterine corpus. The tumors consisted of medium- to large-sized cells exhibiting a diffuse pattern of growth with a well-circumscribed leiomyoma. The neoplastic cells strongly expressed CD79α, CD20 and PAX5. Molecular analyses indicated clonal B-cell receptor gene rearrangement.

Conclusions

To the best of our knowledge, no previous cases of primary DLBCL arising from a leiomyoma have been reported. It is necessary to differentiate a diagnosis of primary DLBCL arising from a leiomyoma from that of leiomyoma with florid reactive lymphocytic infiltration (lymphoma-like lesion). Careful analysis of clinical, histological, immunophenotypic, and genetic features is required to establish the correct diagnosis.

A unique case of an indolent myometrial T-cell lymphoproliferative disorder with phenotypic features resembling uterine CD8+ resident memory T cells

OBJECTIVE

Indolent extranodal T-cell lymphoproliferative disorders have recently been described as new entities in the gastrointestinal tract and acral sites displaying clonal T-cell receptor (TCR) rearrangement and nonactivated cytotoxic CD8+ T-cell phenotypes.

METHODS/RESULTS

We report a unique case of an atypical myometrial T-cell lymphoproliferation in a 39-year-old multiparous woman, which shares many of the features mentioned above: CD8+/TIA1+/granzyme B- phenotype, clonal TCR rearrangement and indolent course.

CONCLUSION(S)

We hypothesize that it might derive from a subset of uterine nonrecirculating CD8+ resident memory T cells expanded after repeated exposure to allo-extravillous trophoblastic antigen.

Early neoplastic lymphoid lesions

The differential diagnosis between neoplastic and reactive lymphoid proliferations is a relatively common situation, which in most cases is resolved using conventional morphological and phenotypic criteria. In the last years, a number of studies have identified different types of lymphoid lesions sharing pathological and molecular features of both benign and malignant processes that are difficult to interpret. A group of these lesions correspond to atypical lymphoid hyperplasias, including follicular hyperplasias, atypical marginal zone hyperplasias, and florid reactive lymphoid hyperplasias of the lower female genital tract in which immunoglobulin light chain restriction with or without clonal IGH rearrangements may be found in some cases. However, these lesions are usually self-limited and do not evolve to an overt lymphoid neoplasia. A second group of lesions are clonal expansions of cells with phenotypic or molecular features of well-defined lymphoid neoplasias, such as chronic lymphocytic leukemias, follicular lymphomas, or mantle cell lymphomas, occurring in otherwise healthy individuals or in the context of reactive lymphoid tissues. In this review, we discuss the criteria to distinguish these lesions from overt lymphomas and the current recommendations for the management of the individuals in which these lesions are found.

Lymphoma of the cervix

Primary non-Hodgkins lymphoma of the uterine cervix is a very rare diagnosis. A 54-year-old woman presented with a 3-month history of postmenopausal bleeding per vaginum. On examination, a friable, fungating lesion was seen on the cervix. Histology revealed a CD 20 positive high-grade non-Hodgkin's diffuse large B cell lymphoma from cervical biopsies and endometrial curettage. She was diagnosed as stage IE after workup and subsequently treated with six cycles of R-CHOP chemotherapy followed by radiotherapy of the involved field.

Primary malignant lymphoma of the uterine cervix

Primary malignant lymphoma of the female genital tract is an extremely rare clinical entity. We report a case of primary non-Hodgkin lymphoma of the uterine cervix. An 85-year-old woman presented with abnormal genital bleeding. A colposcopic examination revealed a mass in the uterine cervix. No other lesions were detected by the whole-body CT, gallium scintigraphy and bone marrow examination. The histological examination and immunohistochemical staining of the cervical biopsy material confirmed a diagnosis of diffuse large B cell lymphoma of the uterine cervix, clinical stage 1E (according to the Ann Arbor Staging Classification for Lymphomas). The patient was treated with rituximab, cyclophosphamide, hydroxydaunorubicin, vincristine (oncovin) and prednisone. Her family refused surgery and involved field irradiation. She was in good condition but after 5 months she expired due to myocardial infarction.

Florid reactive lymphoid hyperplasia (lymphoma-like lesion) of the uterine cervix

Lymphoma-like lesion (LLL) of the female genital tract is an older term in the literature that describes a florid reactive lymphoid proliferation that can be misinterpreted as lymphoma. Multiple causes of LLL have been suggested but most cases remain unexplained. We describe the clinicopathologic features of 6 patients with LLL involving the uterine cervix. Five patients presented with abnormal Papanicolaou test (Pap smear), and 3 patients had a biopsy procedure performed prior to detection of LLL in a loop electrosurgical excision procedure (LEEP). In each specimen, surface epithelial erosion was associated with a superficial, polymorphous lymphoid infiltrate with numerous scattered large cells, without cellular necrosis or sclerosis. Squamous dysplasia was present in 4 patients. Immunohistochemical studies revealed a mixed population of B- and T-lymphoid cells. T-cells were more numerous but B-cells and formed aggregates or sheets in areas. The large cells were predominantly B-cells positive for CD20 and negative for CD3 in all cases. CD30 was positive 3 cases, and Epstein-Barr virus-encoded RNA was positive in 3 cases. Assessment for clonality in 1 patient using polymerase chain reaction (PCR) methods revealed monoclonal immunoglobulin heavy chain (IgH) gene rearrangements. At last clinical follow-up there was no evidence of progressive or systemic disease. We conclude that LLL of the cervix has a number of etiologies and that a prior surgical procedure, present in 3 patients in this study, is another possible etiology. As has been reported by others, monoclonal IgH gene rearrangements can be detected in this entity which has a benign clinical course.

Isolated vaginal myeloid sarcoma in a 16-year-old girl

Involvement of the female genital tract by myeloid sarcoma as the initial presentation is extremely uncommon, especially in the vagina. The lack of specific histologic features and the unusual location can be a diagnostic challenge to both the surgical pathologist and the clinician. The very few reported cases of myeloid sarcoma occurring in the vagina have been exclusively seen in adults. We report a 16-year-old girl who presented with a vaginal mass of 4 weeks duration. The initial clinical impression was a Bartholin cyst vs an abscess. However, because of persistence of the vaginal mass after a full course of antibiotic treatment, a biopsy was performed. Immunohistochemistry supported the diagnosis of myeloid sarcoma. Peripheral blood and bone marrow studies were normal. The patient received 4 cycles of chemotherapy and remained disease free 5 months from therapy completion. The clinical course, diagnostic workup, and differential diagnosis of our patient are discussed. Reported cases of myeloid sarcoma occurring in the vagina are reviewed and summarized.

An operative case of hepatic pseudolymphoma difficult to differentiate from primary hepatic marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue

Hepatic pseudolymphoma (HPL) and primary hepatic marginal zone B cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma) are rare diseases and the differential diagnosis between these two entities is sometimes difficult. We herein report a 56-year-old Japanese woman who was pointed out to have a space occupying lesion in the left lateral segment of the liver. Hepatitis viral-associated antigen/antibody was negative and liver function tests including lactic dehydrogenase, peripheral blood count, tumor markers and soluble interleukin-2 receptor were all within normal limit. Imaging study using computed tomography and magnetic resonance imaging were not typical for hepatocellular carcinoma, cholangiocarcinoma, or other metastatic cancer. Fluorodeoxyglucose-positron emission tomography examination integrated with computed tomography scanning showed high standardized uptake value in the solitary lesion in the liver. Under a diagnosis of primary liver neoplasm, laparoscopic-assisted lateral segmentectomy was performed. Liver tumor of maximal 1.0 cm in diameter was consisted of aggregation of lymphocytes of predominantly B-cell, containing multiple lymphocyte follicles positive for CD10 and bcl-2, consistent with a diagnosis of HPL rather than MALT lymphoma, although a definitive differentiation was pending. The background liver showed non-alcoholic fatty liver disease/early non-alcoholic steatohepatitis. The patient is currently doing well with no sign of relapse 13 months after the surgery. Since the accurate diagnosis is difficult, laparoscopic approach would provide a reasonable procedure of diagnostic and therapeutic advantage with minimal invasiveness for patients. Considering that the real nature of this entity remains unclear, vigilant follow-up of patient is essential.

Unifocal and multifocal reactive lymphoid hyperplasia vs follicular lymphoma of the ocular adnexa

PURPOSE

To characterize the differentiating histopathologic and immunophenotypic features of reactive lymphoid hyperplasia (RLH) and follicular lymphoma of the ocular adnexa.

DESIGN

Retrospective case study with clinical follow-up and review of the literature.

METHODS

Clinical records of 9 cases of RLH and 6 cases of follicular lymphoma from 2 institutions were reviewed. Light microscopic evaluation and immunohistochemical stains including CD20, CD3, CD5, CD21, CD23, BCL-2, BCL-6, CD10, kappa, lambda, and Ki67 were used to distinguish the 2 categories.

RESULTS

RLH preferentially involved the conjunctiva, whereas follicular lymphoma had a propensity to involve the lacrimal gland. Microscopic analysis with immunohistochemical staining distinguished RLH from follicular lymphoma. BCL-2 was positive in follicular centers of follicular lymphoma but not in RLH. CD10 identified follicular center cells and Ki67 quantified cells in S-phase. CD21 and CD23 detected dendritic cell scaffoldings of indistinct germinal centers. None of the patients with RLH developed lymphoma during their clinical courses (up to 18 years). However, 3 patients with orbital, but not conjunctival, RLH developed immunohistochemically proven multifocal nonophthalmic supradiaphragmatic adnexal RLH (sites included lung, parotid, axillary nodes, and uvea). All 6 patients with follicular lymphoma had disseminated disease.

CONCLUSIONS

A correct diagnosis of RLH vs follicular lymphoma can be reliably established employing immunohistochemical methods. A heretofore undescribed "multifocal RLH" syndrome must be distinguished from follicular lymphoma. Conjunctival RLH can usually be managed surgically without radiotherapy, but "multifocal RLH" required systemic treatment in 2 of 3 patients. Follicular lymphoma requires systemic chemotherapy if discovered beyond stage 1E.