Miguel Angel Martínez-González

Fine Needle Aspiration of Chromophobe Renal Cell Carcinoma

OBJECTIVE To describe the cytomorphologic findings of chromophobe renal cell carcinoma (CRCC) in order to preoperatively distinguish this rare neoplasm from other primary or secondary tumors arising from the kidney or presenting as retroperitoneal masses. STUDY DESIGN Clinical data, fine needle aspiration (FNA) and follow-up surgical specimens from 4 patients with CRCC (3 primaries and 1 metastatic to the liver) were reviewed. Electron microscopy was available for 2 histologic specimens. RESULTS Two tumors (1 primary and 1 metastatic case) were readily identified as CRCC on FNA. The 2 remaining cases were diagnosed as renal cell carcinoma (RCC) consistent with CRCC. All tumors showed aspirates with moderate to high cellularity, with the cells arranged in small clusters and single cells. Neoplastic cells had abundant heterogeneous cytoplasm, a thickened cell membrane, nuclear hyperchromasia, nuclear outline irregularity, significant nuclear size variation, intranuclear inclusions and frequent binucleation. Histology of the 4 renal tumors was characteristic of CRCC, with positivity for Hales colloidal iron in all cases. Ultrastructurally, characteristic cytoplasmic microvesicles were observed in the 2 cases that we studied. CONCLUSION In the adequate clinicoradiologic setting, CRCC has distinctive cytologic features that may allow an accurate preoperative FNA diagnosis.

Cutaneous signet ring cell carcinoma a report of a case and review of the literature

Primary cutaneous signet-ring cell carcinoma (CSRCC) is a very unusual but distinctive clinicopathologic entity. It is defined as a diffuse malignant epithelial neoplasia localized in dermis and subcutis without epidermal involvement, showing variable amounts of signet ring cells, without evidence of a visceral adenocarcinoma. We report a case of CSRCC in a 70-year-old man along with its histologic and ultrastructural characteristics, and review of previous cases. We describe their main diagnostic features and discuss its wide differential diagnosis.

Cutaneous presentation on the eyelid of primary, systemic, CD30+, anaplastic lymphoma kinase (ALK)‐negative, anaplastic large‐cell lymphoma (ALCL)

Aim  To report an unusual case of cutaneous presentation on the eyelid of systemic (or nodal), CD30+, anaplastic large‐cell lymphoma (ALCL).

Fine needle aspiration of breast myofibroblastoma. A case report.

BACKGROUND The use of fine needle aspiration cytology (FNAC) for the diagnosis of breast diseases in men has received little attention. We report the cytologic and histologic findings of myofibroblastoma of the breast in a 52-year-old man. CASE Smears disclosed irregular and cohesive sheets of cells, with ill-defined cytoplasm and oval nuclei containing single nucleoli. The nuclear membrane was frequently grooved, and occasional intranuclear cytoplasmic inclusions (pseudoinclusions) were also found. The background was clean and contained scarce collagenous stroma and fragments of myxoid material. To the best of our knowledge, there have been only seven previous reports of breast myofibroblastoma in which the cytologic features are well documented, and none of them mention the presence of pseudoinclusions. CONCLUSION FNAC could suggest the diagnosis of this distinctly uncommon tumor if evaluated together with the clinical and radiologic findings.

Lymphoepithelial cyst with crystalloid formation. Cytologic features of two cases.

BACKGROUND The presence of amylase crystalloids (AC) in cystic lesions of the parotid gland is a rare occurrence and has been diagnosed to date as sialadenitis. We report the first two cases of parotid lymphoepithelial cyst (LC) containing this type of crystalloid. CASES Case 1, a 56-year-old male, presented with a 3-cm parotid cyst. Fine needle aspiration (FNA) was performed on the mass. Smears showed numerous crystalloids identical to those described as crystallized amylase. Case 2, a 36-year-old female, had a 2-cm parotid mass. FNA smears exhibited the same features as did case 1. The two patients were treated with superficial parotidectomy, and an LC containing AC was diagnosed in both cases. CONCLUSION When the above findings are present on FNA of parotid gland, the diagnosis of LC must be considered.

Acral peeling skin syndrome: report of two cases.

Peeling skin syndrome is a rare dermatosis characterized by spontaneous and painless peeling of the skin. The authors report two patients with history of spontaneous, asymptomatic, and noninflammatory peeling skin of the acral surfaces after soaking in water. On light microscopy, blisters were located in the mid layers of the stratum corneum, above the granular layer. Ultrastructural examination revealed increased intercellular lipids and abnormal, “moth-eaten,” keratohyalin granules, but the authors were unable to determine whether the separation initiated within the horny cells or between adjacent cells. These patients represented a localized variant of peeling skin syndrome.

ULTRASTRUCTURAL STUDY OF A PERINEURIOMA WITH RIBOSOME-LAMELLA COMPLEXES

The participation of the perineurial cell in peripheral nerve tumors is the subject of much debate. The case of a 75-year-old female with a soft tissue tumor on her left shoulder is presented. The tumor had histological, ultrastructural, and immunohistochemical characteristics of a pure perineurial cell neoplasm. Ultrastructurally, distinctive ribosome-lamella complexes were found in the cytoplasm of the perineurial cells. This may be the first time that these structures have been described in perineurioma.

Undifferentiated carcinoma of the jejunum with extensive rhabdoid features. Case report and review of the literature.

Malignant rhabdoid tumor, first described in the kidney of young infants, is a rare and highly aggressive neoplasm of controversial histogenesis that has been reported at many other sites, including the gastrointestinal tract. However, malignant rhabdoid tumor of the small intestine is very rare, with only seven cases published to date. We report a 70‐year‐old man who presented with abdominal pain and weight loss, and showed a perforated jejunal mass with disseminated metastases by imaging. The patient underwent partial jejunectomy and biopsy of a liver metastasis. Microscopically, the tumor was characterized by neoplastic cells with vesicular nuclei, large nucleoli and abundant eccentric cytoplasm with hyaline globular intracytoplasmic inclusions. Immunohistochemically, the neoplasm coexpressed vimentin and epithelial antigens (AE1/AE3, Cam 5.2, CK34βE12, CK19 and EMA), most of them showing a peculiar immunostaining pattern in relation to the globular inclusions. Ultrastructurally, the inclusions corresponded to paranuclear whorls of intermediate filaments. The patient received postoperative chemotherapy but died 9 months after surgery. In summary, we report the exceptional case of an undifferentiated carcinoma of the jejunum with rhabdoid phenotype. As with tumors at other sites, recognition of rhabdoid morphology in small intestine neoplasms is of significance because the prognosis is extremely poor.

Clear Cell Atypical Fibroxanthoma: Clinicopathological Study of 6 Cases and Review of the Literature With Special Emphasis on the Differential Diagnosis.

Abstract:Atypical fibroxanthoma (AFX) is an uncommon dermal-based neoplasm arising on the sun-damaged skin of elderly people. Clear cell AFX is a rare variant with only 12 cases reported until the present date, all of them as case reports, except for 1 small series of 3 cases. The authors report 6 new cases and review the literature with special emphasis on the differential diagnosis. The clear cell variant represents 5% of AFX from their files. Histopathologically, it consists of sheets of epithelioid, pleomorphic cells, intermixed with a varying number of giant multinucleated and spindle cells, the latter arranged in a fascicular pattern. All cell types predominantly exhibit a clear, microvacuolated cytoplasm with well-demarcated cell borders. The clinical and immunohistochemical features of this variant are similar to those of the classic type. Clear cell AFX must be differentiated from other cutaneous clear cell neoplasms, some of them with an aggressive clinical behavior, including clear cell melanoma, primary cutaneous and metastatic clear cell carcinomas, clear cell sarcoma, pleomorphic liposarcoma, tumor of perivascular epithelioid cells, and distinctive dermal clear cell mesenchymal neoplasm. The clinical presentation and immunohistochemical profile play a key role in the differential diagnosis.