Clinical presentation of epithelioid angiomyolipoma

OBJECTIVE: Epithelioid angiomyolipomas (AML) of the kidney are malignant tumors with aggressive clinical behavior. METHODS: We reviewed cases of epithelioid AML recently diagnosed at our institution to highlight the spectrum of clinical presentations. RESULTS: In all cases, renal lesions seen on computed tomography were suspicious for renal cell carcinoma (RCC). Histologically, these tumors can resemble RCC. The diagnosis of epithelioid AML was established by positive staining for melanoma and smooth muscle cell markers, and presence of perivascular epithelioid cells. One patient presented with a renal tumor extending into the inferior vena cava to the level of the hepatic veins. Two patients developed recurrent, metastatic disease following nephrectomy. One patient with tuberous sclerosis and multiple, bilateral AML developed an enhancing renal tumor that did not contain any fat densities. A partial nephrectomy was performed and pathology revealed epithelioid AML adjacent to conventional AML. CONCLUSIONS: These tumors are distinguished from RCC by positive immunostaining for melanoma markers and smooth muscle cell markers. They resemble conventional RCC on imaging. Epithelioid AML may be locally aggressive and metastasize.     

Nasopharyngeal granulomatous inflammation and tuberculosis complicating undifferentiated carcinoma.

OBJECTIVE: Four cases of nasopharyngeal granulomatous inflammation after radiotherapy for undifferentiated carcinoma were analyzed for tuberculosis, and the histologic features were compared. STUDY DESIGN AND SETTING: We conducted a retrospective study with analysis of tuberculosis by Ziehl Neelsen staining and polymerase chain reaction analysis for Mycobacterium tuberculosis DNA on histologic materials. RESULTS: Three patients had previous nasopharyngeal undifferentiated carcinoma, one had previous metastatic undifferentiated carcinoma to cervical lymph nodes, and all patients received similar radiotherapy regimen. The light microscopic features were similar with epithelioid histiocytes and granulomas with Langhan's giant cells. In 3 cases, acid-fast bacilli were identified by Ziehl Neelsen stain, and 1 was negative. The results of 2 cases were confirmed by polymerase chain reaction analysis for Myocbacterium tuberculosis DNA. CONCLUSION: Granulomatous reaction after radiotherapy of nasopharyngeal undifferentiated carcinoma can be caused by tuberculosis. SIGNIFICANCE: Diligent search for organisms in postirradiation granulomatous inflammation is warranted to avoid missing an occult tuberculosis infection.     

Suppression associated lymphocyte markers in lesions of sarcoidosis.

The presence within the epithelioid granulomas of sarcoidosis of lymphocytes of the "helper" (T4 positive) phenotype suggests that, as in granulomatous diseases of known aetiology, active cell mediated immunity plays a part in the disease. It has, however, been noted that T8 positive lymphocytes are also found on occasion in the granulomas. The presence of cells bearing markers associated with suppressor activity in various lesions of sarcoidosis has been investigated with a range of monoclonal antibodies. T4 positive cells were present in all granulomas; T8 positive lymphocytes were present within the epithelioid cell areas in proportions that varied from 5 to 55/100 of T4 cells. Other lymphocyte markers associated with suppression (Leu8 and SN130) were very rare on lymphocytes within granulomas but common on both T4 positive and T8 positive lymphocytes in the perigranulomatous mantle, which suggests that expression of these markers was down regulated in the granuloma or that cells bearing them are unable to migrate into the granuloma. Nevertheless, suppressor cell mechanisms could mediate the spontaneous resolution of most cases of sarcoidosis, and the presence or absence of cells bearing suppression associated phenotypes in the granuloma or its mantle may have prognostic importance.     

Mucinous tubular and spindle cell carcinoma of the kidney with sarcomatoid change

Sarcomatoid change has been well documented in the various subtypes of renal cell carcinoma (RCC) and its presence is known to portend a worse prognosis in RCC. Mucinous tubular and spindle cell carcinoma is a RCC subtype, which is defined as polymorphous histology wherein the spindled epithelial cell is an inherent carcinomatous component. Many of these putatively low-grade tumors have been previously misdiagnosed as unclassified or sarcomatoid papillary RCC. We present 2 examples of hitherto undescribed sarcomatoid change in mucinous tubular and spindle cell carcinoma in a 71-year-old woman and an 80-year-old man who both underwent a radical nephrectomy procedure. In addition to the classic mucinous tubular and spindle cell carcinoma morphology, both cases had a sarcomatoid component characterized by predominantly high-grade spindle cells, solid pleomorphic epithelioid cells, and malignant fibrous histiocytoma-like storiform patterns. Sarcomatoid change comprised 60% and 20% of the tumors, respectively. Unlike the spindle sarcomatoid cells, the inherent spindle cell elements of mucinous tubular and spindle cell carcinoma had distinctively low-grade cytology and occasionally blended with tubular structures and variable mucinous stroma. The sarcomatoid cells were associated with significant necrosis, marked nuclear pleomorphism, mitoses of up to 5/10 high power field, higher proliferation fraction (MIB1), and loss of alpha-methylacyl-CoA racemase or cytokeratin 7 expression. Cytogenetic analysis in 1 tumor showed loss of chromosomes 14 and 15 and gains of chromosomes 2, 5, 7, 9, 10, 12, 17, 19, 20, 22, and X. Widespread metastasis to lymph nodes, bones and lungs occurred in one patient who succumbed 9 months after nephrectomy. Helpful features in distinguishing spindle cells of sarcomatoid component versus that of the native tumor include the presence of high-grade cytology, expansile growth with loss of typical imperceptible blending with the tubulo-papillary component, extensive necrosis, high mitotic activity, high proliferation fraction, and loss of expression of alpha-methylacyl-CoA racemase that contrasted the classic areas. Distinction of the sarcomatoid histology from inherent spindle cell component of mucinous tubular and spindle cell carcinoma is important because of its unfavorable prognostic implication.     

Granulomatous reaction in lymph nodes draining laryngeal carcinoma

Presented are two cases of simultaneous occurrence of epithelioid granulomas and metastatic squamous cell carcinoma in cervical lymph nodes draining supraglottic carcinoma. Laboratory tests and radiological and clinical findings ruled out sarcoidosis, as well as mycotic, mycobacterial, or other bacterial infection. Upon finding of epithelioid granulomas in cervical lymph nodes, a malignant tumor of the head and neck region should be considered as a differential diagnostic possibility. Uncritical acceptance of a diagnosis based solely on the histological appearance may lead to erroneous treatment.     

A case of hepatocellular carcinoma with tuberculoma within tumor tissue

We made a diagnosis of hepatocellular carcinoma and performed partial resection of the liver in a 72 year-old woman. Granulomas were observed within hepatocellular carcinoma in the surgical specimen. Microscopic findings demonstrated the granulomas particularly within the tumor, and showed that they were composed of epithelioid cells with caseous necrosis. These tuberculomas compressed the tumor cells, and many lymphocytes had infiltrated the tumor around the tuberculomas. The cancer stage of the patient was early and her prognosis is good.     

The role of Yersinia enterocolitica and Yersinia pseudotuberculosis in granulomatous appendicitis: a histologic and molecular study

Granulomatous appendicitis is an enigmatic entity. Purported causes include Crohn's disease, foreign body reactions, sarcoidosis, and infectious agents; however, most cases remain idiopathic. Yersinia enterocolitica (YE) and Y. pseudotuberculosis (YP) have been implicated as causes of appendicitis, ileocolitis, and mesenteric adenitis. The authors examined the potential role of YE and YP in granulomatous appendicitis using histologic and molecular methods. Forty cases of granulomatous appendicitis were evaluated for histologic features including transmural inflammation, number and character of granulomas, and mucosal changes. Twort Gram, Grocott methenamine-silver (GMS), and Ziehl-Neelsen stains were evaluated, and polymerase chain reaction (PCR) analysis was performed to identify pathogenic YP and YE. Twenty-five percent (10 of 40) of the cases were positive for pathogenic Yersinia by PCR (four YE, four YP, and two with both species). Prominent histologic features included epithelioid granulomas with lymphoid cuffing, transmural inflammation with lymphoid aggregates, mucosal ulceration, and cryptitis. One Yersinia-positive case contained mural Gram-negative bacilli; fungal and acid-fast bacilli stains were all negative. Except for one culture-negative case, serologies and cultures were not done or results were unavailable. Two Yersinia-positive patients were diagnosed subsequently with Crohn's disease, suggesting a possible relationship between the two entities. No other patients developed significant sequelae. YE and YP are important causes of granulomatous appendicitis, and Yersinia infection may mimic Crohn's disease. No histologic features distinguish reliably between Yersinia species, or between Yersinia-positive and Yersinia-negative cases. Because special stains and cultures are often not diagnostic, PCR analysis is an excellent technique for the diagnosis of Yersinia.     

Clear cell myomelanocytic tumor of the urinary bladder

Clear cell myomelanocytic tumors are a recently described neoplastic growth considered to be a member of the family of perivascular epithelioid cell tumor. These tumors have a predilection for falciform ligament/ligamentum teres. We report an additional case arising from the muscularis propria of the urinary bladder in a 33-year-old woman. The tumor consisted of clear to eosinophilic, epithelioid, and spindled cells arranged in fascicles or packets. A delicate vascular stroma was found among the nests. Immunohistochemically, the tumor cells were typically positive for HMB-45 and smooth muscle actin but negative for S-100 protein, Melan-A, desmin, and pan-cytokeratin. The patient has been free of the disease since the excision of the tumor 6 years ago. This case, in association with the expanding list of perivascular epithelioid cell tumor reported in different sites, suggests that this type of neoplasm may be ubiquitous.     

肾细胞癌患者抑癌基因VHL双等位基因

目的探讨肾细胞癌患者中抑癌基因VHL的双等位基因失活发生情况.方法在41例肾细胞癌患者中提取肿瘤和正常组织DNA.采用单链聚合酶链反应(PCR)和测序法检测肿瘤组织中VHL基因的突变情况.采用PCR限制性片段长度多态性法检测VHL基因内部的2个单核苷酸多态性(SNP)位点,在2个位点的杂合子中通过对比肿瘤组织和正常肾组织分析VHL基因的杂合性丢失(LOH)情况.结果在肾细胞癌中51%(21/41)发生VHL基因突变,42%(8/19)发生VHL基因LOH,基因突变和LOH发生具有显著一致性(r=0.78),在37%(7/19)的肾细胞癌中发生VHL双等位基因失活.结论肾细胞癌中存在由VHL基因突变和LOH导致的VHL双等位基因失活现象,VHL双等位基因失活发生率为37%.     

Correlation of presence of granulomas with clinical and immunologic variables in Crohn's disease

Approximately 50% of patients with Crohn's disease have epithelioid granulomas present in the diseased intestine. Some studies have associated the presence of granulomas with a good prognosis. In this prospective study, 44 patients with Crohn's disease requiring surgery were followed up for five years. Twenty-two patients (50%) had granulomas. Patients with granulomas were younger and had a shorter duration of disease. They also had more extensive disease and a greater degree of peripheral lymphopenia. Follow-up showed a trend toward greater recurrence rate in the patients with granulomas. It seems that patients with aggressive and extensive Crohn's disease are not protected from the development of symptomatic early recurrence by the presence of epithelioid granulomas.     

Granulomatous variants of cutaneous T-cell lymphoma. The histopathology of granulomatous mycosis fungoides and granulomatous slack skin

Granulomatous mycosis fungoides is an unusual histologic variant of mycosis fungoides, a condition that is ordinarily indolent. Granulomatous slack skin, like granulomatous mycosis fungoides, shows epidermotropism, granulomatous inflammation, a clonal T-helper cell population, and progression to systemic lymphoma in some cases. Unlike granulomatous mycosis fungoides, it is characterized clinically by bulky, pendulous skin folds. The similarities between the two conditions prompted us to compare the histologic features. We reviewed 24 biopsies from 10 patients with granulomatous mycosis fungoides. These showed several distinct histologic patterns, including three cases that mimicked granuloma annulare. We also reviewed biopsy specimens from four patients with granulomatous slack skin. These specimens had a more stereotypic appearance, with permeation of the entire dermis and subcutis by lymphocytes, marked epidermotropism, and a more even distribution of granulomas and giant cells within the infiltrate. Biopsies of fully developed lesions of granulomatous slack skin showed elastolysis involving the full thickness of the dermis--a feature not seen in any of our granulomatous mycosis fungoides cases. Biopsy specimens from granulomatous mycosis fungoides and granulomatous slack skin may be mistaken for nonneoplastic granulomatous dermatitides, but they can usually be distinguished from these by the presence of epidermotropism or atypical lymphocytes. Because several of our patients with granulomatous mycosis fungoides died after courses of unremarkable length, it seems unlikely that the presence of granulomas is invariably correlated with a more benign course than nongranulomatous mycosis fungoides.     

Sclerosing Rhabdomyosarcoma: Presentation of a Rare Sarcoma Mimicking Myoepithelial Carcinoma of the Parotid Gland and Review of the Literature

Sclerosing rhabdomyosarcoma (SRMS), a recently characterized variant of rhabdomyosarcoma, can pose a significant diagnostic challenge given its rarity and its histological similarity to other malignancies. SRMS is characterized by dense hyalinized or sclerosing collagenous matrix and a pseudovascular pattern of growth. SRMS shares histologic similarities with several mesenchymal tumors including: leiomyosarcoma, osteosarcoma, chondrosarcoma, angiosarcoma, and sclerosing epithelioid fibrosarcoma. We herein report a case of SRMS mimicking a myoepithelial carcinoma of the parotid gland. The tumor contained small, spindled, and epithelioid tumor cells lining pseudovascular spaces within a dense hyalinized stroma. Initial stains for keratins, S100 and p63 were negative. However the tumor cells showed desmin and myogenin positivity. The tumor was negative for FKHR gene rearrangements and showed no MDM2 gene amplification. This is the second case of SRMS to be diagnosed in the parotid gland highlighting the potential for misdiagnosis as a primary salivary gland epithelial malignancy.     

P53 and her-2 alterations in renal cell carcinoma

ObjectivesTo investigate protein expression and genetic aberrations of p53 and HER-2 in renal cell carcinoma (RCC) as well as possible association of p53 and HER-2 abnormalities with the tumor behavior of RCC.MethodsFormalin-fixed and paraffin-embedded tissue blocks from 70 patients with RCC were studied. Protein expression of p53 and HER-2 was assessed immunohistochemically. Following deoxyribonucleic acid extraction from the paraffin sections using a microdissection technique, p53 gene mutations within exons 5 to 8 were examined by polymerase chain reaction (PCR) single-strand conformation polymorphism and HER-2 gene amplification by a differential PCR.ResultsOf the 70 RCCs, 16 (22.9%) showed protein expression of p53, with 7 (10%) demonstrating mutations within exons 5 to 7. Additionally, 28 RCCs (40%) displayed protein expression of HER-2, with 12 (17.1%) demonstrating gene amplification. All cases showing p53 mutations or HER-2 amplification represented protein expression of p53 or HER-2, respectively. No cases with negative immunostaining for p53 or HER-2 protein displayed positive results at gene level. Statistical analysis revealed a close relationship between p53 protein expression and the tumor grade, as well as a significant association of HER-2 protein expression and gene amplification with the tumor stage of RCC.ConclusionsOur observations suggest that the abnormalities of p53 and HER-2 may be involved in the pathogenesis of RCC and that other mechanisms leading to protein expression of p53 and HER-2 may coexist within a single tumor in addition to the genetic aberrations.     

Epithelioid hemangioendothelioma of the brain.

Epithelioid hemangioendothelioma is a recently described vascular neoplasm characterized by epithelioid tumor cells and borderline biologic behavior. Its four principal sites of occurrence are the soft tissue, liver, lung, and bone. We report a case of primary cerebral epithelioid hemangioendothelioma in a 4-month-old male infant. The tumor consisted of loose aggregates of epithelioid cells with a focal cordlike or bridging-branching pattern, supported in a fibromyxoid stroma. The tumor cells displayed frequent intracytoplasmic vacuoles. Immunohistochemically, the tumor cells showed positive staining for Ulex europaeus agglutinin, vimentin, and cytokeratin. The tumor pursued an indolent clinical course. The patient was alive 28 months after initial presentation, but he was left with a severe neurological deficit because of the location and growth of the tumor.     

Florid granulomatous reaction in Epstein-Barr virus-positive nonendemic Burkitt lymphomas: report of four cases

Epithelioid cell granulomas have been reported in association with a wide range of neoplasms including malignant lymphomas. In lymphoma, this refers mainly to Hodgkin disease and T-cell-derived non-Hodgkin lymphomas where a granulomatous reaction is probably evoked by aberrant cytokine production in the tumor cells or other cells composing the tumor background. Here we report on four cases of sporadic Burkitt lymphoma with unusual florid granulomatous reaction. In all samples, the tumor cells were admixed with numerous epithelioid cells that formed clusters and granulomatous lesions. No microorganisms could be detected at the tissue level, and there were no clinical or laboratory indications of an underlying immunodeficiency. The lymphomas harbored a specific morphology and immunophenotype of Burkitt lymphoma, and the presence of translocation breakpoint in MYC gene was confirmed by interphase fluorescence in situ hybridization. In all four patients, the lymphoma was associated with Epstein-Barr virus infection, detected by EBER in situ hybridization and the latency I phenotype as defined by lack of expression of LMP1. All four patients were treated with polychemotherapy, achieved a complete remission, and are alive without evidence of disease. We draw attention to this unusual phenomenon as it caused difficulties in interpretation and delayed diagnosis and hypothesize on the possible role of Epstein-Barr virus products.     

Low-grade fibromyxoid sarcoma and hyalinizing spindle cell tumor with giant rosettes share a common t(7;16)(q34;p11) translocation

Low-grade fibromyxoid sarcoma (LGFMS) is a rare metastasizing soft tissue tumor with deceptively bland histologic features. The hyalinizing spindle cell tumor with giant rosettes (HSCT) is thought to be a closely related tumor differing only by the presence of collagen rosettes. We report the occurrence of a common t(7;16)(q34;p11) translocation in 2 cases of HSCT and 2 cases of LGFMS, thereby providing the first cytogenetic proof that LGFMS and HSCT are variants of the same entity. The tumors occurred in the thighs of 2 females and in the buttock and supraclavicular fossa of 2 males. One HSCT had a spectrum of unusual histologic features, including the presence of plump epithelioid cells with abundant cytoplasm and strands and nests of clear epithelioid cells separated by eosinophilic hyalinized stroma. Two cases showed a hitherto unreported, focal staining with epithelial membrane antigen, thus adding to the immunohistochemical profile of these tumors. LGFMS and HSCT probably have a wider spectrum of morphologic features than previously thought, the awareness of which will help pathologists to avoid diagnostic pitfalls. Demonstration of the t(7;16)(q34;p11) translocation will help to diagnose difficult cases with unusual histologic features.     

Granulomatous mastitis — a diagnostic dilemma

Granulomatous lobular mastitis is a rare benign breast disease. It is characterized by chronic, non-caseating granulomatous lobulitis. It may be misdiagnosed as a carcinoma of the breast and may lead to mastectomy. Diagnostic criteria include-A) Granulomatous infl ammation with multinucleated giant cells, epithelioid histiocytes. B) It is centered on lobules with minor ductal and periductal infl ammation. C) It nearly always follows the pregnancy. A case of GLM, which was treated with local excision and postoperative steroid therapy is being reported to increase awareness amongst surgeons and pathologist.