Sporadic Renal Angiomyolipoma: Can We Adopt a Uniform Management Protocol / Angiomiolipoma renal esporádico: ¿Podemos adoptar un protocolo de tratamiento estándar?

Renal angiomyolipomas (AMLs), formerly known as PEComas (tumors showing perivascular epithelioid cell differentiation) are common benign renal masses composed of a varying ratio of fat, blood vessels, and smooth muscles. They are largely asymptomatic and diagnosed incidentally on imaging. The adipose tissue content is the factor that gives AMLs their characteristic appearance on imaging and makes them easily identifiable. However, the fat-poor or fat-invisible varieties, which are difficult to differentiate radiologically from renal cell carcinomas (RCCs), present a diagnostic challenge. It is thus essential to establish the diagnosis and identify the atypical and hereditary cases as they require more intense surveillance and management due to their potential for malignant transformation. Multiple management options are available, ranging from conservative approach to embolization and to the more radical option of nephrectomy. While the indications for intervention are relatively clear and aimed at a rather small cohort, the protocol for follow-up of the remainder of the cohort forming the majority of cases is not well established. The surveillance and discharge policies therefore vary between institutions and even between individual practitioners. We have reviewed the literature to establish an optimum management pathway focusing on the typical AMLs.

Los angiomiolipomas renales (AML), antes conocidos como PEComas (tumores que muestran epitelioides perivasculares) son masas renales benignas frecuentes compuestas por una proporción variable de grasa, vasos sanguíneos y músculos lisos. Suelen ser asintomáticos y se diagnostican de forma incidental en las pruebas de imagen. El contenido de tejido adiposo es el factor que confiere a los AML su aspecto característico en las imágenes y los hace fácilmente identificables. Sin embargo, las variedades pobres en grasa o invisibles, que son difíciles de diferenciar radiológicamente de los carcinomas de células renales (CCR), suponen un reto diagnóstico. Por lo tanto, es esencial establecer el diagnóstico e identificar los casos atípicos y hereditarios, ya que requieren una vigilancia y un tratamiento más intensos debido a su potencial de malignización. debido a su potencial de transformación maligna. Existen múltiples opciones de tratamiento, que van desde el enfoque conservador hasta la embolización y la opción más radical de la nefrectomía. Si bien las indicaciones para la intervención son relativamente claras y están dirigidas a una cohorte bastante pequeña, el protocolo para el seguimiento del resto de la cohorte que forma la mayoría de los casos no está bien establecido. Por lo tanto, las políticas de vigilancia y alta varían entre instituciones e incluso entre profesionales individuales. Hemos revisado la literatura para establecer una ruta de manejo óptima centrada en los AML típicos.

Primary pituitary tuberculosis

Tuberculosis is an infectious disease that involves any organ. However, the primary pituitary tuberculosis is an extremely rare disease. Intracranial tuberculomas account for 0.15-5% of intracranial space-occupying lesions, of which, pituitary as the primary site is unusual, and easily misdiagnosed as pituitary adenoma. In this setting, the late diagnosis can result in permanent endocrine dysfunction. We report the case of a 50-year-old woman who presented to the neurosurgery outpatient department with complaints of progressively increasing headache and diminished vision over the last year. On the clinical examination, the patient was conscious and oriented. The routine hematological and biochemical workup showed an increased erythrocyte sedimentation rate (ESR) and increased prolactin levels. The radiological working diagnosis was consistent with pituitary macroadenoma. No other radiological and/or clinical clue that could elicit the suspicion of pulmonary or extrapulmonary lesions of tuberculosis was found. The transsphenoidal endonasal tumor excision was done. The histopathology showed numerous epithelioid cell granulomas, Langhans giant cells along with scant necrosis. Ziehl Neelsen staining demonstrated acid-fast bacilli, and the final diagnosis of pituitary tuberculoma was made. We report this rare case of pituitary lesion that may be included in the differential diagnosis of sellar lesions to avoid unnecessary surgical interventions, especially in regions where the disease is endemic.

Epithelioid inflammatory myofibroblastic sarcoma: the youngest case reported

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare variant of the inflammatory myofibroblastic tumor. It has an aggressive clinical course and a high rate of recurrence. EIMS primarily affects children and young adults. Hereby, we report this entity in a 4-month-old infant who presented with an abdominal mass. Imaging studies revealed a large hypodense mesentery-based lesion involving the right half and mid-region of the abdomen. The mass with an attached segment of the small bowel was excised in toto. Grossly, a large encapsulated tumor was identified arising from the mesentery of the small bowel. The histological examination showed a tumor consisting of epithelioid to spindle cells loosely arranged in a myxoid background with numerous blood vessels and lymphoplasmacytic inflammatory infiltrate. On immunohistochemistry, the tumor cells showed positivity for ALK1 (nuclear), desmin, SMA, CD68, and focal positivity for CD30. A final diagnosis of EIMS of the small intestine was rendered. To the best of our knowledge, this case is the youngest reported case in literature.

Epithelioid angiomyolipoma with tumor thrombus in IVC and right atrium

Epithelioid angiomyolipoma is an uncommon subtype of renal angiomyolipoma associated with potentially malignant behavior and is considered a distinct entity by the World Health Organization classification of renal tumors. We present a case of an epithelioid variant of angiomyolipoma with extension into the renal vein, inferior vena cava reaching up to the right atrium. Pre-operatively, a diagnosis of renal cell carcinoma was considered based on imaging findings. Intra-operatively due to extensive adhesions, surgical resection was not performed and only tissue sampling was performed for histopathology. Microscopic examination revealed short fascicles of spindle cells and perivascular epithelioid cells. A differential diagnosis of renal cell carcinoma with sarcomatoid differentiation was considered. The immunohistochemical profile showed tumor cells that express Melan-A and smooth muscle actin, while they were negative for pan-cytokeratin, PAX8, CK7, CD117 and CD34. Therefore a diagnosis of epithelioid angiomyolipoma was rendered. The presence of intravascular thrombi on radiological investigation and carcinoma-like growth pattern on light microscopy may compound an erroneous diagnosis of renal cell carcinoma. Hence, it is prudent for the urologist to consider differential diagnosis other than renal cell carcinoma when confronted with a renal neoplasm presenting with intravascular thrombi. In these cases, a core biopsy should be planned pre-operatively and diagnosis should be made with aid of appropriate immunohistochemical markers.

Primary Malignant Melanoma of the Breast: A Report of Two Cases

Primary malignant melanoma of the breast (PMMB) is a rare tumor with only a few case reports available in the literature. We report two cases of PMMB, one derived from the breast parenchyma and the other from the breast skin. The first case consisted of atypical epithelioid cells without overt melanocytic differentiation like melanin pigments. The tumor cells showed diffuse positivity for S100 protein, tyrosinase, and BRAF V600E. However, the tumor cells were negative for cytokeratin, epithelial membrane antigen, and HMB-45. The second case showed atypical melanocytic proliferation with heavy melanin pigmentation. The tumor cells were positive for S100 protein, HMB-45, tyrosinase, and BRAF V600E. These two cases represent two distinct presentations of PMMB in terms of skin involvement, melanin pigmentation, and HMB-45 positivity. Although PMMB is very rare, the possibility of this entity should be considered in malignant epithelioid neoplasms in the breast parenchyma.

Solitary Fibrous Tumor of Breast with Anaplastic Areas (Malignant Solitary Fibrous Tumor): A Case Report with Review of Literature / 한국유방암학회지

Solitary fibrous tumor (SFT) is a rare, soft tissue neoplasm that rarely presents in breast tissue, with only 27 previously reported cases. To our knowledge, only one case of malignant SFT has been reported in the English literature. A 75-year-old Caucasian woman presented to our institution with a 3-month history of a palpable left breast mass. No other symptoms, including nipple discharge or skin changes, were noted. She underwent 3 previous biopsies for right breast masses, all of which were benign, with no evidence of spindle cell neoplasm, atypical hyperplasia, or malignancy. Microscopic examination of the mass demonstrated a classic area of SFT with areas of high-grade anaplastic component. In these areas, the tumor showed atypical epithelioid cells arranged in hypercellular sheets with diminished branching vasculature, nuclear pleomorphism, and increased mitotic count (up to 9/10 high-power fields). This case represents the second case of malignant SFT in the breast.

TFE3-Expressing Perivascular Epithelioid Cell Tumor of the Breast

Perivascular epithelioid cell tumor (PEComa) is a very rare mesenchymal tumor with a distinctive morphology and immunophenotype. PEComas usually harbor TSC2 alterations, although TFE3 translocations, which occur in MiT family translocation renal cell carcinoma and alveolar soft part sarcoma, are also possible. We recently experienced a case of PEComa with TFE3 expression arising in the breast. An 18-year-old female patient presented with a right breast mass. Histologically, the tumor consisted of epithelioid cells with alveolar structure and showed a diffuse strong expression of HMB45 and TFE3. TSC2 was preserved. Melan A and smooth muscle actin were negative. To our knowledge, this is the first Korean case of PEComa of the breast that intriguingly presented with TFE3 expression.

Two Cases of Lupus Miliaris Disseminatus Faciei Treated with Oral Mini-pulse Steroid Therapy / 대한피부과학회지

Lupus miliaris disseminatus faciei (LMDF) is a rare granulomatous skin disease mainly affecting the central area of the face. A variety of treatments are reportedly of some benefit; however, controlled studies to establish the best treatment are lacking. Here, we report the cases of a 33-year-old man who presented with multiple, various-sized, erythematous maculopapules on the face and a 19-year-old man who presented multiple, reddish papuloplaques distributed on the face. Histopathological examinations of the two cases revealed large clear-boundary epithelioid cell granulomas with central necrosis surrounded by lymphocytic infiltration. Based on the clinical and histological findings, diagnoses of LMDF were made. As oral tetracycline and antimalarials were not fully effective in our cases, oral mini-pulse steroid therapy (dexamethasone, 5 mg bid for 2 days per week) was initiated. After several months, the eruption significantly improved, and most lesions were resolved. Here, we report two cases of LMDF successfully treated with oral mini-pulse steroid therapy.

A Case of Epithelioid Hemangioendothelioma on the Choana

Epithelioid hemangioendothelioma is a rare vascular tumor with intermediate malignity and metastasis risk. It presents epithelioid cells with intracytoplasmic vacuoles and low mitotic activity. Its vascular nature can be confirmed by immunohistochemical studies (vimentin, CD31, CD34, and factor VIII). It is extremely rare in the nasal cavity, with only one case reported on the middle turbinate in Korea. The authors present a case of epithelioid hemangioendothelioma on the choana with a size of 2mm, which easily coult have been misdiagnosed as a blood clot.

Epithelioid Cell Histiocytoma on the Palm Mimicking Pyogenic Granuloma / 대한피부과학회지

No abstract available.

Lupus miliaris disseminatus faciei

Abstract: Lupus miliaris disseminatus faciei is a rare inflammatory dermatosis of unknown etiology that primarily affects young adults. Clinically, it is characterized by an asymptomatic papular eruption mainly involving the central face, typically on and around the eyelids. Characteristic histopathological features include dermal epithelioid cell granulomas with central necrosis and surrounding lymphocytic infiltrate with multinucleate giant cells. Lupus miliaris disseminatus faciei has a spontaneously resolving course, yet can be cosmetically debilitating given the location and potential for scarring. Treatment is difficult and there is a lack of controlled studies. We report a new case of lupus miliaris disseminatus faciei successfully treated with minocycline and systemic steroids, and briefly discuss its nosology and therapeutic options.

Perivascular Epithelioid Cell Tumor in the Stomach

Perivascular epithelioid cell tumors or PEComas can arise in any location in the body. However, a limited number of cases of gastric PEComa have been reported. We present two cases of gastric PEComas. The first case involved a 62-year-old woman who presented with a 4.2 cm gastric subepithelial mass in the prepyloric antrum, and the second case involved a 67-year-old man with a 5.0 cm mass slightly below the gastroesophageal junction. Microscopic examination revealed that both tumors were composed of perivascular epithelioid cells that were immunoreactive for melanocytic and smooth muscle markers. Prior to surgery, the clinical impression of both tumors was gastrointestinal stromal tumor (GIST), and the second case was erroneously diagnosed as GIST even after microscopic examination. Although gastric PEComa is a very rare neoplasm, it should be considered in the differential diagnosis of gastric submucosal lesions.

Hepatic perivascular epithelioid cell tumor (PEComa): a case report with a review of literatures

Hepatic perivascular epithelioid cell tumors (PEComas) are very rare. We report a primary hepatic PEComa with a review of the literature. A 56-year-old women presented with a nodular mass detected during the management of chronic renal failure and chronic hepatitis C. Diagnostic imaging studies suggested a nodular hepatocellular carcinoma in segment 5 of the liver. The patient underwent partial hepatectomy. A brown-colored expansile mass measuring 3.2×3.0 cm was relatively demarcated from the surrounding liver parenchyma. The tumor was mainly composed of epithelioid cells that were arranged in a trabecular growth pattern. Adipose tissue and thick-walled blood vessels were minimally identified. A small amount of extramedullary hematopoiesis was observed in the sinusoidal spaces between tumor cells. Tumor cells were diffusely immunoreactive for human melanoma black 45 (HMB45) and Melan A, focally immunoreactive for smooth muscle actin, but not for hepatocyte specific antigen (HSA).

Epithelioid angiomyolipoma of the liver: a case report

Epithelioid angiomyolipoma (EAML) of liver is a rare neoplasm. Hepatic EAML is often misdiagnosed as other neoplasms such as hepatocellular carcinoma due to non-specific clinical and radiologic features. The morphologic features under microscope and immunohistochemistry staining profile are important in the diagnosis EAML. Here, we report a case of 52-year-old man who found 1.2 cm mass in liver by routine checkup. On the impression of hepatocellular carcinoma, lateral sectionectomy of the liver was done. Microscopically, the tumor is composed of predominant epithelioid cells with vascular component and foamy cells. These cells were positive for HMB45, MelanA, and smooth muscle actin and negative for epithelial membrane antigen. The final diagnosis was hepatic EAML.

Epithelioid myxofibrosarcoma: a clinicopathologic analysis of 10 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate clinicopathologic features, pathologic diagnosis, differential diagnosis and biological behavior of epitheioid myxofibrosarcoma (EMFS).</p><p><b>METHODS</b>The clinical and pathological data of 10 cases were collected, and microscopic examination and immunostains were performed along with a review of the literatures.</p><p><b>RESULTS</b>There were 5 males and 5 females with age ranging from 53 to 74 years, and the mean and median age was 63.6 and 62.5 years, respectively. Six cases developed in the extremities, including upper limbs (n=3) and lower limbs (n=3). Three developed in the trunk and 1 case in the mesentery of sigmoid colon. Tumor size ranged from 4.2 to 7.0 cm (mean, 5.3 cm). Most patients presented with painless masses with duration of 1 to 24 months (mean, 8 months). All 10 patients were treated by surgery, with adjunctive chemotherapy and/or radiotherapy in 4 patients and interventional therapy in 1 patient. Histologically, 8 cases were high grade and 2 were intermediate grade. Like the conventional myxofibrosarcomas, all primary tumors presented a multinodular growth pattern consisting of hypocellular myxoid and hypercellular areas. Prominent curvilinear vessels and pseudolipoblasts were observed in the hypocellular myxoid areas. Besides the spindled neoplastic cells, all tumors were characterized by a variable proportion of epithelioid cells with vesicular nuclei, prominent nucleoli and moderate to abundant eosinophilic cytoplasm. They were arranged singly or in small clusters in the myxoid areas, and in compact sheets in the solid areas. The epithelioid component comprised 30% to 90% of the tumors. In addition, areas with resemblance to undifferentiated pleomorphic sarcoma were also noted, especially in the recurrent tumors. Immunohistochemically, tumor cells showed diffuse staining of vimentin in 6 tested cases with focal expression of smooth muscle actin and epithelial membrane antigen in 1 case each. Ki-67 index ranged from 30% to 80% (mean, 58%). Follow-up data (range, 2 to 74 months; mean, 23 months) were available in 10 cases: 4 patients were alive with unresectable or recurrent disease and 6 patients were alive with no evidence of disease. Five patients experienced local recurrence and 2 cases developed metastasis. The median interval to recurrence/metastasis was 7 months (mean, 9 months).</p><p><b>CONCLUSIONS</b>The presence of epithelioid cells in a myxofibrosarcomatous background portends an aggressive clinical behavior.EMFS should be differentiated from other myxoid sarcomas with epithelioid morphology.</p>

Hepatic angiomyolipoma: a clinicopathologic features and prognosis analysis of 182 cases / 中华病理学杂志

<p><b>OBJECTIVE</b>To study the clinicopathological characteristics of hepatic angiomyolipoma (HAML) and to evaluate the correlation between clinicopathological parameters and tumor subtypes.</p><p><b>METHODS</b>Retrospective analysis of clinicopathological features was conducted in 182 cases of HAML.</p><p><b>RESULTS</b>HAML patients were predominantly female (M:F=1:4) and most commonly presented with non-specific symptoms. The median age at diagnosis was 46 years, ranged from 17 to 77 years. Tumor diameter was ranged from 0.3 to 32.0 cm with an average of 5.0 cm. Majority of the tumor was epithelioid type (112/165, 67.9%). Extramedullary hematopoiesis, multinucleated giant cells, intranuclear inclusions, nucleolus, cellular atypia, invasive growth pattern, multiple masses, hyperpigmentation and purpura-like changes mostly occurred in the epithelioid type (P<0.05). Extramedullary hematopoiesis was commonly seen in HAML, the significance of which was still uncertain.</p><p><b>CONCLUSIONS</b>Most of HAML are epithelioid type, characterized by a proliferation of predominantly epithelioid cells, in which extramedullary hematopoiesis is commonly seen. Some morphologic features that may predict malignant such as necrosis, mitotic figures, and tumor emboli are only found in the epithelioid HAML. Mitotic activity, tumor necrosis, tumor thrombus, giant cells, periportal invasion, multiple lesions and tumors size over 10 cm are closely related with tumor recurrence and metastasis.</p>

Cellular Neurothekeoma of the Scalp in the Elderly

Cellular neurothekeoma (CNT) is an uncommon variant of neurothekeoma that is composed of pithelioid to spindled cells with variable nuclear atypia or pleomorphism but no myxoid stroma. CNT occurs predominantly in the head and neck or upper trunk of children and young adults, with female predominance. The following case is different from typical CNTs. An 88-year-old female presented with a palpable mass on the scalp, which we excised. Histologically, the tumor was non-encapsulated and composed of spindled and epithelioid cells arranged in fascicles and nodules separated by a collagen-rich stroma. Immunohistochemical analysis showed that the epithelioid and spindle-shaped cells were focally positive for vimentin, neuron-specific enolase, smooth muscle actin, CD68, and CD10 but negative for S-100 protein, HMB-45, epithelial membrane antigen, and CD34. We report a new case of CNT that arose in the scalp of an older patient and that was associated with uncommon clinical, histological, and immunohistochemical profiles.

Cellular Neurothekeoma of the Scalp in the Elderly

Cellular neurothekeoma (CNT) is an uncommon variant of neurothekeoma that is composed of pithelioid to spindled cells with variable nuclear atypia or pleomorphism but no myxoid stroma. CNT occurs predominantly in the head and neck or upper trunk of children and young adults, with female predominance. The following case is different from typical CNTs. An 88-year-old female presented with a palpable mass on the scalp, which we excised. Histologically, the tumor was non-encapsulated and composed of spindled and epithelioid cells arranged in fascicles and nodules separated by a collagen-rich stroma. Immunohistochemical analysis showed that the epithelioid and spindle-shaped cells were focally positive for vimentin, neuron-specific enolase, smooth muscle actin, CD68, and CD10 but negative for S-100 protein, HMB-45, epithelial membrane antigen, and CD34. We report a new case of CNT that arose in the scalp of an older patient and that was associated with uncommon clinical, histological, and immunohistochemical profiles.

Pathomorphological features of calcinosis circumscripta in a dog / 한국실험동물학회지

A 19-month-old male German shepherd dog was presented with a hindlimb footpad mass. The mass was excised and histopathology was performed. Grossly, the cut section of the mass had multiple well-circumscribed nodules with a chalky appearance. Histopathologically, basophilic-stained calcium deposits of various sizes were distributed from dermis to subcutis, surrounded by epithelioid cells, multinucleated giant cells, and reactive fibroblasts. Myxoid metaplasia, calcium deposits in hair follicles, and psammoma-like bodies were also found. These histopathologic observations will greatly help to understand the pathogenesis of calcinosis circumscripta.