Primary hepatic pleomorphic liposarcoma: Case report and literature review / Liposarcoma pleomorfo hepático primario: presentación de un caso y revisión bibliográfica

Primary hepatic liposarcoma is an extremely rare malignant tumour derived from adipocytes and is part of the group of mesenchymal tumours. We present the case of a 43-year-old Hispanic male patient with a pleomorphic hepatic liposarcoma and absence of MDM2 gene amplification. Two years and six months after surgery, the patient is asymptomatic. The present case is the first report of this entity with positive immunohistochemical testing for p16, p53, S100, vimentin and absence of MDM2 gene amplification. (AU)

El liposarcoma hepático primario es un tumor maligno extremadamente raro, derivado de adipocitos, y forma parte del grupo de tumores mesenquimales. Presentamos el caso de un paciente masculino de 43 años con diagnóstico de liposarcoma hepático pleomorfo con ausencia de amplificación del gen MDM2. Dos años y 6 meses después de la cirugía el paciente se encuentra asintomático. El presente caso es el primer informe de esta entidad con estudio inmunohistoquímico positivo para p16, p53, S100, vimentina y ausencia de amplificación del gen MDM2. (AU)

Primary hepatic pleomorphic liposarcoma: Case report and literature review.

Primary hepatic liposarcoma is an extremely rare malignant tumour derived from adipocytes and is part of the group of mesenchymal tumours. We present the case of a 43-year-old Hispanic male patient with a pleomorphic hepatic liposarcoma and absence of MDM2 gene amplification. Two years and six months after surgery, the patient is asymptomatic. The present case is the first report of this entity with positive immunohistochemical testing for p16, p53, S100, vimentin and absence of MDM2 gene amplification.

Melanocytic nevus of the anal canal and granular cell tumor of the cecum: a case report and literature review of 2 coincidentally co-occurring neurocristopathies.

Granular cell tumors are predominantly benign soft tissue tumors originating from Schwann cells, whereas melanocytic nevi are benign proliferations of melanocytes. We present the case of a patient with the presence of both entities located in the cecum and anal canal, respectively, constituting an extremely rare coincidental finding. A 43-year-old woman was evaluated by colonoscopy for iron-deficiency microcytic anemia that had lasted for 1 year. Colonoscopy demonstrated a macular lesion of 0.3 cm with a melanocytic appearance in the anal canal; at the cecum level, a subepithelial, yellowish, and partially mobile firm nodular lesion measuring 1.3 cm was observed. A histopathological study showed a melanocytic nevus in the anal canal and a granular cell tumor in the cecum. This is the first reported case of a patient with the extremely rare coincidental-incidental finding of these 2 entities at the same time.

Case Report: Desmoid fibromatosis in the mediastinum of a 6-month-old toddler, what to do?

Desmoid fibromatosis is a rare, aggressive borderline lesion arising from soft tissues. Treatment will depend on the structures that the tumor has involved. Surgery with negative margins is the recommended strategy as it can usually achieve disease control; however, the tumor's location sometimes does not allow it. Therefore, a combination of medical therapies along with strict surveillance is crucial. We present the case of a 6-month-old boy with a chest mass. After further evaluation, a rapidly growing mediastinal mass involving the sternum and costal cartilage was detected. Desmoid fibromatosis was the final diagnosis.

Primary splenic histiocytic sarcoma associated with hemophagocytic lymphohistiocytosis: A case report and review of literature of next-generation sequencing involving FLT3, NOTCH2, and KMT2A mutations.

BACKGROUND: Histiocytic sarcoma is a very rare monocyte/macrophage-derived hematopoietic system tumor with a poor prognosis whose diagnosis is pathologically challenging due to its extreme rarity and histological overlap with various mimicking entities in which histiocytes also predominate. CASE: We report the case of a 33-year-old male patient with hemophagocytic lymphohistiocytosis, purpuric syndrome, and significant splenomegaly. The patient underwent splenectomy; subsequent macroscopic examination revealed a spleen weighing 2065 grams with hyperemic red pulp and multiple infarcts at the periphery. The histological and immunohistochemical study established a diagnosis of primary splenic histiocytic sarcoma with frequent hemophagocytosis. Next-generation sequencing demonstrated mutations in FLT3, NOTCH2, and KMT2A, microsatellite stability, and a tumor mutational burden of 2 mut/Mb. The patient's condition deteriorated clinically from the appearance of the first symptoms and he died 6 months later from multi-organ failure. CONCLUSION: Primary splenic histiocytic sarcoma is one of the rarest tumors of the hematopoietic system. We report the first case with mutations in FLT3, NOTCH2, and KMT2A, and associated hemophagocytic lymphohistiocytosis.

Primary cutaneous diffuse large B-Cell lymphoma, leg type mimicking subcutaneous panniculitis-like T-cell lymphoma in a COVID-19 setting: case report and review of literature.

Primary cutaneous diffuse large B-cell lymphoma, leg type is a rare entity accounting for 4% of all primary cutaneous lymphomas whose clinical presentation encompasses a range of possibilities. COVID-19 has caused a delay in diagnosis of malignant neoplasms and consequently, this has resulted in poorer prognoses. A 62-year-old woman presented with two smooth-surfaced, mobile, well-circumscribed, oval, skin-colored nodules approximately one-cm in diameter with nonerythematous borders on the lower third of the left leg. Two months later, eleven nodules measuring between one and 1.5cm with erythematous halo, slight scaling, central erosion, and crusting had appeared. Histological study showed moderate pericapillary lymphocytic infiltration in the papillary and reticular dermis and prominent diffuse proliferation of medium to large cells in the subcutis. These exhibited irregular vesicular nuclei, a conspicuous solitary nucleolus of two to three small nucleoli, and three mitoses per high power field. Adipocytes were consistently encircled by neoplastic lymphocytes. Primary cutaneous diffuse large B-cell lymphoma, leg type is a high-grade lymphoma that can manifest as a diagnostic challenge and requires adequate immunohistochemistry and in situ hybridization studies for proper diagnosis, treatment, and prognosis.

Osteocondromatosis sinovial de hombro. Una enfermedad poco frecuente / Shoulder synovial osteocondromatosis. A rare disease

RESUMEN La osteocondromatosis sinovial es una condición poco común que se caracteriza por la formación de nódulos cartilaginosos u óseos comúnmente visto en las articulaciones sobretodo en la rodilla, sin embargo en el hombro esta condición es rara. Presentamos un caso clínico de una mujer de 35 años de edad con dolor en hombro izquierdo de larga evolución, tratado de manera conservadora antes de ser referido a un ortopedista. Luego de un diagnostico clínico y radiológico se sometió a tratamiento quirúrgico en la que se realizó un desbridamiento y escisión de los cuerpos condrales con éxito. Palabras claves: Condromatosis sinovial, tratamiento, adulto joven, mujer

ABSTRACTSynovial osteochondromatosis is a rare condition characterized by the formation of cartilage or bone nodules commonly seen in the joints, especially in the knee, however, this condition is rare in the shoulder. We present a clinical case of a 35-year-old woman with a long history of left shoulder pain, treated conservatively before being referred to an orthopedist. After a clinical and radiological diagnosis, she underwent surgical treatment in which a successful debridement and excision of the chondral bodies was performed

Cutaneous Myoepithelioma: An Unusual Tumor in the Hand.

Cutaneous myoepithelioma (CM) is a rare tumor among the primary skin neoplasms. We present the case of a patient with a diagnosis of CM in the right hypothenar region. Histological study showed a proliferation of myoepithelial cells with a solid, reticular growth pattern in a chondromyxoid stroma. The tumor cells were positive for CK AE, S-100, EMA, and p63.

Mesonephric adenocarcinoma of the cervix: a case report with a three-year follow-up, lung metastases, and next-generation sequencing analysis.

BACKGROUND: Mesonephric adenocarcinoma (MNAC) is a rare tumor of the female genital tract, which originates from mesonephric duct remnants. Its diagnosis is pathologically challenging, because MNAC may exhibit a mixture of morphological patterns that complicates the differential diagnosis. CASE PRESENTATION: The patient in this case was a 48-year-old woman with a polypoid mass protruding into the endocervical canal. The patient underwent a total hysterectomy outside the institution. During biopsy, the mass showed a cerebroid aspect. Histological study revealed a tumor with a predominantly tubular and ductal growth pattern. The immunoprofile showed negative staining for calretinin, carcinoembryonic antigen (CEAm), estrogen receptors (ER), and progesterone receptors (PR), and positive staining for CD10, p16, and PAX2. The Ki-67 score was 46%. Using a next-generation sequencing assay, we documented genomic alterations in KRAS and CTNNB1, low tumor mutation burden (TMB), and an absence of microsatellite instability. In addition, gain of the long arm of chromosome 1 (1q) was also documented using chomogenic in situ hybridization (CISH). Three years later, the patient presented pulmonary nodules in the lingula and left basal lobe that were resected by thoracotomy. The histopathologic study of the pulmonary nodules confirmed the presence of metastases. CONCLUSION: Carcinomas of mesonephric origin are among the rarest subtypes of cervical tumors. We report the first case of mesonephric adenocarcinoma of the cervix with lung metastases showing a CTNNB1 gene mutation.

Immunophenotypic characteristics of diffuse large b-cell lymphoma and expression of C-MYC protein: single Ecuadorian center experience / Características inmunofenotípicas del linfoma difuso de células grandes B y expresión de la proteína C-MYC: experiencia en un centro de Ecuador

Abstract Background: Diffuse large B-cell lymphoma (DLBCL) makes up from 25% to 40% of all non-Hodgkin lymphomas (NHL) and is the most common histological subtype worldwide. In Ecuador, DLBCL makes up 49% of all NHL cases, but there have been no studies on the immunophenotypic classificationof DLBCL in germinal center (GC) and non-germinal center (NGC)subtypes.This study was conducted to ascertain the immunophenotypic profile of DLBCL in an Ecuadorian hospital. Methods: A total of 38 DLBCL cases from 2006 to 2015 were compiled from the Pathology Service at Metropolitan Hospital (HM) in Quito, Ecuador. Eleven of these cases failed to meet the inclusion criteria; thus, the final sample consisted of 27 cases. Manual tissue microarrays were constructed, and three immunohistochemical markers (CD10, BCL6, and MUM1) were applied according to the Hans algorithm; in addition, the expression of the c-myc protein expression was also investigated. Results: The results showed that 77.8% of cases were of the GC subtype, 11.1% were NGC, and 11.1% were unclassifiable according to the Hans algorithm. Conclusions: The most frequent DLBCL subtype was GC, with 21 cases; and 40.7% of these cases overexpressed c-myc.

Resumen Antecedentes: El linfoma difuso de células grandes B (LDCGB) constituye el 25 al 40% del total de los linfomas no Hodgkin (LNH) y es el subtipo histológico más frecuente en el mundo. En Ecuador el LDCGB corresponde al 49% del total de los casos de LNH, sin embargo no hay estudios de clasificación inmunofenotípica del LDCGB en centro germinal (CG) y no centro germinal (NCG). Este estudio se realizó para conocer el perfil inmunofenotípico del LDCGB en un hospital de Ecuador. Métodos: Se recopiló del Servicio de Patología del Hospital Metropolitano de Quito, Ecuador, un total de 38 casos de LDCGB desde el 2006 al 2015, de los cuales 11 no cumplieron con los criterios de inclusión. La muestra final fue de 27 casos. Se realizaron microarreglos tisulares manuales para la aplicación de tres marcadores de inmunohistoquímica según el algoritmo de Hans (CD10, BCL6 y MUM1) y luego se correlacionó con la sobreexpresión de la proteína c-MYC. Resultados: El 77,8% de casos fue tipo CG, 11,1% fue NCG y 11,1% fueron inclasificables según Hans. Conclusiones: El subtipo de LDCGB más frecuente fue CG con 21 casos y de estos 40,7% sobreexpresaron c-MYC.

Secretory Carcinoma of the Parotid: Making the Correct Diagnosis of a Rare Salivary Gland Carcinoma When Molecular Biology Testing Is Not Available.

Secretory carcinoma (SC) is a recently described entity occurring in the salivary glands. Before its description, SC was frequently classified as acinic cell carcinoma (ACC) or adenocarcinoma, not otherwise specified. Its particular histopathological and immunohistochemical characteristics are reminiscent of breast secretory carcinoma. Moreover, it displays a characteristic t(12;15) (p13;q25) translocation that results in the ETV6-NTRK3 gene fusion. This translocation has not been reported in any other salivary gland carcinoma. Identification of the t(12;15) (p13;q25) translocation is the gold standard for diagnosis, although some cases that do not present this specific translocation have already been reported. In such cases, diagnosis is challenging. In addition, some diagnostic pathology laboratories lack the resources to perform the molecular analysis to diagnose SC. In this scenario, morphology and immunohistochemistry are fundamental. Therefore, we report a case emphasizing the typical morphology of SC and its immunochemical profile to establish a final diagnosis without molecular biology tests. This case aims to demonstrate the importance of recognizing the typical presentation of a rare tumor so that clinicians will be informed or reminded of it and consider this entity among the differential diagnoses, when necessary. Moreover, in low-resource settings where molecular analysis is not available, being familiar enough with the histology of this tumor and using the immunoprofile as a key tool for differential diagnosis would be of great importance in establishing the correct diagnosis. The differential diagnosis includes, above all, acinic cell carcinoma and other salivary neoplasms such as intraductal carcinoma, low-grade mucoepidermoid carcinoma, and adenocarcinoma, not otherwise specified, which is actually a rule-out diagnosis.

Vulvar Myxoid Liposarcoma, an Extremely Rare Diagnosis: A Case Report and Review of Literature.

Malignant lipomatous tumors of the vulva are extremely rare. We report the case of a 53-year-old patient with a nodule on her right labium majus whose histological and immunohistochemical profile (S100 and p16) confirmed a diagnosis of vulvar myxoid liposarcoma.

Nuevos horizontes y direcciones futuras en la teranóstica del linfoma difuso de células grandes B / New horizons and future directions in the theranostics of diffuse lymphoma of large B cells

El linfoma difuso de células grandes B (LDCGB) abarca 25 a 40% del total de los linfomas no Hodgkin (LNH) y es el subtipo histológico más frecuente en el mundo. En Ecuador, el LDCGB corresponde al 49% del total de los casos de LNH. La Organización Mundial de la Salud (OMS) planteó, en 2008, una clasificación que incluye variantes morfológicas y subtipos moleculares e inmunofenotípicos. Los subtipos inmunofenotípicos se identifican según el algoritmo de Hans (CD10, Bcl-6 y MUM-1) y se clasifican, con fines pronósticos en: centro germinal (CG) y no-centro germinal (NCG). Los nuevos hallazgos de caracterización molecular del LDCGB (como traslocaciones cromosómicas recurrentes del myc, Bcl2 y Bcl-6) permiten desarrollar terapias blanco.(AU)

Diffuse large B-cell lymphoma (DLBCL) makes up from 25% to 40% of all non-Hodgkin lymphomas (NHL) and is the most common histologic subtype worldwide. In Ecuador, DLBCL amounts to 49% of all NHL cases. In 2008, the World Health Organization (WHO) put forth a classification that includes morphological variants and molecular and immunophenotypic subtypes. The immunophenotypic subtypes are identified by the Hans algorithm (CD10, Bcl-6, MUM-1) and are classified as germinal center (GC) and nongerminal center (NGC). The new molecular characterization findings of LDCGB as recurrent chromosomal translocations of myc, Bcl2 and Bcl-6, allow the development of target therapies.(AU)

Heterotopic sebaceous glands in the esophagus, a very rare histopathological diagnosis: a case report and review of the literature.

Sebaceous glands are very rarely found in the esophagus. Existing reports do not contain sufficient epidemiological, etiological, clinical, or prognostic data. Its histogenesis suggests heterotopia or metaplasia. Despite its extreme rarity, correct and generally easy identification enables establishing the proper patient monitoring.

Gastritis autoinmunitaria. Abordaje diagnóstico y su relación con los síndromes poliglandulares autoinmunitarios / Autoimmune gastritis. Diagnostic approach and its relationship with autoimmune polyglandular syndromes

La gastritis autoinmunitaria (GAI) es una entidad subdiagnosticada; la mayoría de veces pasa inadvertida con graves consecuencias para la calidad de vida de la persona por sus complicaciones asociadas. Forma, además, parte de un grupo de trastornos autoinmunitarios conocidos como síndromes poliglandulares autoinmunitarios. Hace muchos años la GAI era un trastorno solitario; sin embargo, la reciente asociación con el Helicobacter pylori (HP) ha generado nuevo interés diagnóstico, manejo e incluso prevención de su desarrollo si se sospecha oportunamente. (AU)

Autoimmune gastritis (GAI) is an underdiagnosed entity, most often goes unnoticed with serious consequences on quality of life of the person by their associated complications. It is also part of disorders known as autoimmune polyglandular syndromes. Many years ago the GAI was a lonely disorder, however, the recent association with Helicobacter pylori (HP) has generated new interest in the diagnosis, management and even prevention when clinical suspicion exist. (AU)

Hydroa Vacciniforme-Like EBV-Positive Cutaneous T-Cell Lymphoma, First Report of 2 Cases in Ecuador.

Hydroa vacciniforme-like cutaneous lymphoma is a very rare Epstein-Barr virus positive peripheral T-cell lymphoma affecting Asian and Hispanic children and young adults with a defective cytotoxic immune response to EBV predisposing to the development of the disease. We report on 2 Ecuadorian patients with papulovesicular and ulcerated crusted lesions on the face, upper and lower extremities and abdomen, with aggressive clinical course and, in one case, a fatal outcome. The histological and molecular profiles (immunohistochemistry and in situ hybridization) established a diagnosis of hydroa vacciniforme-like Epstein-Barr virus-encoded small RNAs + cutaneous T-cell lymphoma in both cases.

Secretory Carcinoma in a 79- Year-Old Woman: An Exceptionally Rare Type of Breast Carcinoma.

Secretory breast carcinoma is an exceptionally rare mammary gland neoplasia described mainly in adult females and children of both sexes, and very rarely in the elderly. It has particular histopathological and immunohistochemical features and a favorable prognosis. We report the case of a 79-year-old Hispanic woman with a palpable breast mass. Currently, the patient is disease free after a followup period of 6 years without local recurrence or axillary lymph-nodes nor distant metastases.

Mediastinal Myxoid Liposarcoma with Intrapericardial Involvement and Large Pericardial Effusion.

Liposarcoma is the name given to a group of soft tissue sarcomas (STSs) with adipocytic differentiation. As a group, liposarcomas are the second most common STSs in adults. In 1951 Kozonis et al published that in the English language only four cases of liposarcomas originating in the mediastinum had been described. Primary mediastinal liposarcoma is an uncommon neoplasm of intrathoracic origin. We present the case of a 47-year-old woman diagnosed with a large mediastinal mass with intrapericardial invasion and massive pericardial effusion; biopsies showed a mediastinal liposarcoma.

Incomplete duplication of a lower extremity (polymelia): a case report.

INTRODUCTION: Polymelia, or congenital duplication of a limb, is an extremely rare entity in humans, with few cases reported in the literature. CASE PRESENTATION: We present the case of a six-month-old Hispanic boy born with a lower limb bud on the left posterior thigh. CONCLUSION: The infant had a favorable outcome and evolution after surgical treatment of his supernumerary limb, with no after-effects or impairment whatsoever.

Unusual histopathological diagnosis of prostatic blue nevus: a case report.

INTRODUCTION: Prostatic blue nevus was first described as a benign lesion of uncertain and controversial histogenesis by Nogogosyan in 1963. Currently, 30 cases have been reported in the world literature. CASE PRESENTATION: A 63-year-old Hispanic man presented with prostatism of several months' evolution. Histopathological examination revealed a blue nevus associated with nodular hyperplasia and acute inflammation. CONCLUSION: Prostatic blue nevus is a rare and unusual, histologically benign prostatic lesion with limited clinical significance and a favorable prognosis.