Immunoglobulin Light Chain (AL) Amyloidosis Preceding Marginal Zone Lymphoma: A Case Report.

Immunoglobulin light chain (AL) amyloidosis is a systemic disease in which different systems such as kidneys, heart, and lungs are affected by the deposition of amyloid, a form of fibrillary protein. Usually, it occurs in patients with pre-existing diagnoses of plasma cell dyscrasias and is rarely seen in the concurrence of marginal zone lymphoma (MZL). Earlier interventions with cyclophosphamide and dexamethasone in conjunction with newer therapies such as bortezomib, carfilzomib or lenalidomide, and pomalidomide are being used to treat patients with AL amyloidosis. In this report, we are presenting a unique case of a patient who was diagnosed with AL amyloidosis several years prior to presenting with a soft tissue mass, which was subsequently noted to be an amyloid mass within an MZL. Overall, the occurrence of AL amyloidosis and MZL is rare with less than 20 patients reported. The MZL developed prior to or simultaneously with AL amyloidosis in the reported cases. Therefore, to our knowledge, this is the first time systemic amyloidosis has preceded MZL.

Primary Epithelioid Angiosarcoma of the Uterus: A Rare Tumor with Very Aggressive Behavior.

Angiosarcoma is a high-grade vascular tumor arising from endothelial cells of blood vessels. It represents less than 1% of the mesenchymal tumors. Uterine angiosarcoma is an extremely rare tumor with less than 25 cases reported in the literature. It usually presents in postmenopausal women as uterine mass and rarely can arise in a leiomyoma. It is included in the group of tumors of aggressive behavior and poor prognosis. Herein, we present a case of primary uterine angiosarcoma in a 56-year-old female patient with a history of fibroids presenting with pelvic pain and weight loss. Abdominal CT scan showed a large uterine mass and enlarged pelvic lymph nodes. Total abdominal hysterectomy with bilateral salpingo-oophorectomy was performed, and on histopathologic examination, it was found to be primary epithelioid angiosarcoma of the uterus. Immunohistochemical stains for CD31, keratin MAK-6, and keratin AE1/AE3 confirmed the diagnosis. In conclusion, uterine angiosarcoma should be suspected in any rapidly growing hemorrhagic uterine mass, and appropriate sampling and immunohistochemical stains should be considered.

Therapy-Related Acute Myeloid Leukemia Following TCHP Chemotherapy in Two HER2+ Breast Cancer Patients.

Increased risk for the development of therapy-induced myeloid leukemia following the treatment of breast cancer has typically been associated with the use of regimens containing anthracyclines or alkylating agents. We present two cases of estrogen receptor-positive/progesterone receptor-positive/human epidermal growth factor receptor 2-positive (ER+/PR+/HER2+) breast cancer patients, treated with a non-anthracycline, non-alkylating regimen of trastuzumab, carboplatin, docetaxel, and pertuzumab (TCHP), who developed therapy-related acute myeloid leukemia (t-AML) within 30 months of the completion of treatment. Both patients had marked cytogenetic abnormalities, including deletions of chromosomes 5 and 7, and highly aggressive disease that resulted in a poor prognosis. While platinum and taxane-based chemotherapy regimens have been previously linked to the development of t-AML or therapy-related myelodysplastic syndrome (t-MDS) following treatment for ovarian cancer, they have not yet been shown to increase the risk of t-AML/t-MDS after their use for breast cancer therapy. As TCHP is widely used for the treatment of HER2/neu overexpressed breast cancer, these cases highlight the need to further evaluate the link between taxane and platinum-based chemotherapeutics for breast cancer and the development of t-AML/t-MDS.

Predicting the Behavior of Perivascular Epithelioid Cell Tumors of the Uterine Corpus.

Perivascular epithelioid cell tumors (PEComas) are rare neoplasms that share phenotypic features with angiomyolipomas, clear cell sugar tumors, and lymphangioleiomyomatosis. They presumably represent the neoplastic counterpart of a yet-unidentified perivascular epithelioid cell that expresses smooth muscle and melanocytic immunomarkers. The uterus is the second most common site of origin for perivascular epithelioid cell tumors, after the retroperitoneum. Although most uterine perivascular epithelioid cell tumors are clinically benign and can be cured by a complete surgical excision, there is a subset characterized by both local and distant dissemination. Unfortunately, no single histopathologic or immunohistochemical parameter can accurately predict the clinical behavior of these tumors, which is why the 2012 World Health Organization classification of tumors of the female reproductive organs suggests the use of several criteria to predict the risk of aggressive clinical behavior. Here we review those perivascular epithelioid cell tumors of the uterine corpus with aggressive clinical behavior reported in the literature, and we discuss their most relevant clinical and histopathologic features.

Detailed Histologic Evaluation of Eosinophilic Esophagitis in Pediatric Patients Presenting with Dysphagia or Abdominal Pain and Comparison of the Histology between the Two Groups.

EoE in children presents with four main symptoms. Most common symptoms exhibited by our clinic population are dysphagia (D) and abdominal pain (AP). Despite similar treatments, we found in an earlier study that the outcomes between these two groups were different. Therefore, we investigated if there exist any histological differences between these groups that could further our knowledge of EoE. Aim. To compare esophageal histology in detail, apart from the eosinophil count, between EoE-D and EoE-AP. Method. Biopsies of patients with EoE-D and EoE-AP were reevaluated for 10 additional histological criteria, in addition to the eosinophil count. Results. Both groups had 67 patients; peak mean eosinophil was 33.9 and 31.55 for EoE-D and EoE-AP (p < 0.05). Eosinophilic microabscesses, superficial layering of eosinophils, and epithelial desquamation were twice as common and significant in EoE-D group than EoE-AP. Eosinophil distribution around rete pegs was also significantly higher in EoE-D group. The remaining criteria were numerically higher in EoE-D, but not significant, with the exception of rete peg elongation. Conclusion. EoE-D patients have significantly higher eosinophils compared to EoE-AP, and the level of inflammation as seen from eosinophil microabscesses, superficial layering, desquamation, and the distribution around rete pegs is significantly higher.

Role of monocyte-lineage cells in prostate cancer cell invasion and tissue factor expression.

BACKGROUND: Tissue factor (TF) is a cell surface glycoprotein intricately related to blood coagulation and inflammation. This study was performed to investigate the role of monocyte-lineage cells in prostate cancer cell TF expression and cell invasion. METHODS: Prostate cancer cell invasion was tested with and without added peripheral blood monocytes or human monocyte-lineage cell lines. TF neutralizing antibodies were used to determine the TF requirement for prostate cancer cell invasion activity. Immunohistochemistry was performed to identify prostate tissue CD68 positive monocyte-derived cells and prostate epithelial TF expression. RESULTS: Co-culture of PC-3, DU145, and LNCaP cells with isolated human monocytes significantly stimulated prostate cancer cell invasion activity. TF expression was greater in highly invasive prostate cancer cells and was induced in PC-3, DU145, and LNCaP cells by co-culture with U-937 cells, but not with THP-1 cells. TF neutralizing antibodies inhibited PC-3 cell invasion in co-cultures with monocyte-lineage U-937 or THP-1 cells. Prostate cancer tissues contained more CD68 positive cells in the stroma and epithelium (145 ± 53/mm(2)) than benign prostate (108 ± 31/mm(2)). Samples from advanced stage prostate cancer tended to contain more CD68 positive cells when compared with lower stage lesions. Prostatic adenocarcinoma demonstrated significantly increased TF expression compared with benign prostatic epithelium. CONCLUSIONS: This study shows that co-culture with monocyte-lineage cells induced prostate cancer cell invasion activity. PC-3 invasion and TF expression was induced in co-culture with U-937 cells and partially inhibited with TF neutralizing antibodies.

Downregulation of connective tissue growth factor by three-dimensional matrix enhances ovarian carcinoma cell invasion.

Epithelial ovarian carcinoma (EOC) is a leading cause of death from gynecologic malignancies, due mainly to the prevalence of undetected metastatic disease. The process of cell invasion during intraperitoneal anchoring of metastatic lesions requires concerted regulation of many processes, including modulation of adhesion to the extracellular matrix and localized invasion. Exploratory cDNA microarray analysis of early response genes (altered after 4 hr of 3D collagen culture) coupled with confirmatory real-time reverse-transcriptase polymerase chain reaction, multiple 3D cell culture matrices, Western blot, immunostaining, adhesion, migration and invasion assays were used to identify modulators of adhesion pertinent to EOC progression and metastasis. cDNA microarray analysis indicated a dramatic downregulation of connective tissue growth factor (CTGF) in EOC cells placed in invasion- mimicking conditions (3D Type I collagen). Examination of human EOC specimens revealed that CTGF expression was absent in 46% of the tested samples (n = 41), but was present in 100% of normal ovarian epithelium samples (n = 7). Reduced CTGF expression occurs in many types of cells and may be a general phenomenon displayed by cells encountering a 3D environment. CTGF levels were inversely correlated with invasion such that downregulation of CTGF increased, while its upregulation reduced collagen invasion. Cells adhered preferentially to a surface comprised of both collagen I and CTGF relative to either component alone using alpha6beta1 and alpha3beta1 integrins. Together these data suggest that downregulation of CTGF in EOC cells may be important for cell invasion through modulation of cell-matrix adhesion.

Expression of membrane type 1 matrix metalloproteinase (MMP-14) in epithelial ovarian cancer: high level expression in clear cell carcinoma.

OBJECTIVE: Clear cell carcinomas of the ovary constitute approximately 5% of all ovarian neoplasms and have a distinct gene expression profile relative to other ovarian carcinoma histotypes. Tumors often present as an early stage large pelvic mass with a high degree of recurrence and frequent early metastasis. Matrix metalloproteinases (MMPs) play a role in intraperitoneal metastasis through breakdown of cell-cell and cell-matrix barriers, enabling anchoring of secondary lesions and promoting proliferation in a geometrically constrained matrix environment. The objective of this study was to evaluate MMP expression in ovarian clear cell carcinoma. METHODS: Immunohistochemistry was used to evaluate expression of membrane type 1 MMP (MMP-14), MMP-2 and MMP-9 in a panel of ovarian tumors. Western blotting and gelatin zymography were used to examine MMP-14 expression and activity in the clear cell carcinoma cell line ES2. The ability of ES2 cells to invade and proliferate within three-dimensional collagen gels was evaluated. RESULTS: High level expression of MMP-14 and MMP-2 were observed in ovarian clear cell carcinoma relative to other histotypes (94-95% strong positive). MMP-14 was expressed and active in cultured ES2 cells. ES2 cells also exhibited MMP-dependent invasion of and proliferation within three-dimensional collagen gels. CONCLUSIONS: The high level expression of MMP-14 together with in vitro functional analyses suggest that MMP-14 may contribute to both the proliferative capacity and the enhanced parenchymal metastasis of ovarian clear cell carcinoma.

Glypican-3 as a useful diagnostic marker that distinguishes hepatocellular carcinoma from benign hepatocellular mass lesions.

CONTEXT: Histopathologic distinction between hepatocellular carcinoma (HCC) and benign hepatocellular mass lesions, particularly hepatocellular adenoma, can sometimes be challenging. The currently available ancillary tools are suboptimal in terms of sensitivity and specificity. OBJECTIVE: To further characterize the diagnostic value of glypican-3 (GPC3), a cell surface proteoglycan that has recently been shown to be overexpressed in HCC, in the distinction between HCC and benign hepatocellular mass lesions. DESIGN: A total of 221 surgically resected liver specimens were subjected to immunohistochemical staining using a monoclonal antibody specific for GPC3. These included 111 HCCs, 48 hepatocellular adenomas, 30 focal nodular hyperplasias, and 32 large regenerative nodules in the background of cirrhosis. RESULTS: Cytoplasmic, membranous, and canalicular staining for GPC3 was detected in 84 (75.7%) of the 111 HCCs, among which, 61 (72.6%) of the 84 cases exhibited diffuse immunoreactivity. In contrast, none of the 110 cases of hepatocellular adenoma, focal nodular hyperplasia, and large regenerative nodule showed detectable GPC3 staining. Focal GPC3 immunoreactivity was detected in cirrhotic nodules in 11 (16.4%) of 67 HCC cases with a cirrhotic background, but no background staining was observed in the remaining 44 HCCs without cirrhosis. GPC3 expression in HCCs did not correlate with the size, differentiation, or stage of the tumors; the presence or absence of cirrhotic background; or the underlying etiologies. CONCLUSIONS: GPC3 is a specific immunomarker for HCC that can be used to distinguish HCC from benign hepatocellular mass lesions, particularly hepatocellular adenoma. However, the diagnosis of HCC should not rely entirely on positive GPC3 immunostaining because focal immunoreactivity can be detected in a small subset of cirrhotic nodules. In addition, GPC3 expression in HCC can also be focal, and thus, the lack of GPC3 staining does not exclude the diagnosis of HCC.

Matrix metalloproteinase 9 is a mediator of epidermal growth factor-dependent e-cadherin loss in ovarian carcinoma cells.

Epidermal growth factor (EGF) receptor (EGFR) is frequently elevated in epithelial ovarian cancer, and E-cadherin expression is often reduced in advanced disease. In this study, we investigated a mechanism by which EGFR activation promotes disruption of adherens junctions through induction of matrix metalloproteinase 9 (MMP-9). We show that EGFR activation down-modulates E-cadherin, and broad spectrum MMP inhibition ameliorates EGF-stimulated junctional disruption and loss of E-cadherin protein. MMP-9 involvement in EGF-dependent down-regulation of E-cadherin was determined by siRNA specifically directed against MMP-9. Furthermore, treatment with recombinant MMP-9 or transient expression of MMP-9 is sufficient to reduce E-cadherin levels in differentiated ovarian tumor cells. Stable overexpression of MMP-9 led to a loss of E-cadherin and junctional integrity, and promoted a migratory and invasive phenotype. Thus, elevated MMP-9 protein expression is sufficient for junctional disruption and loss of E-cadherin in these cells. The associations between EGFR activation, MMP-9 expression, and E-cadherin were investigated in human ovarian tumors and paired peritoneal metastases wherein immunohistochemical staining for activated (phospho) EGFR and MMP-9 colocalized with regions of reduced E-cadherin. These data suggest that regulation of MMP-9 by EGFR may represent a novel mechanism for down-modulation of E-cadherin in ovarian cancer.

Motility-related actinin alpha-4 is associated with advanced and metastatic ovarian carcinoma.

Advanced and metastatic ovarian cancer is a leading cause of death from gynecologic malignancies. A more detailed understanding of the factors controlling invasion and metastasis may lead to novel anti-metastatic therapies. To model cellular interactions that occur during intraperitoneal metastasis, comparative cDNA microarray analysis and confirmatory real-time reverse transcription PCR (RT-PCR) were employed to uncover changes in gene expression that may occur in late stage ovarian cancer in response to microenvironmental cues, particularly native three-dimensional collagen I. Gene expression in human ovarian carcinoma tissues was evaluated on the RNA and protein level using real-time RT-PCR and immunohistochemistry. Cell invasion and migration were evaluated in a collagen invasion assay and a scratch wound assay. Three-dimensional collagen I culture led to differential expression of several genes. The role of actinin alpha-4 (ACTN4), a cytoskeleton-associated protein implicated in the regulation of cell motility, was examined in detail. ACTN4 RNA and protein expression were associated with advanced and metastatic human ovarian carcinoma. This report demonstrates that a cytoskeletal-associated protein ACTN4 is upregulated by three-dimensional collagen culture conditions, leading to increased invasion and motility of ovarian cancer cells. Expression of ACTN4 in human ovarian tumors was found to be associated with advanced-stage disease and peritoneal metastases.

Wilms tumor gene protein 1 is associated with ovarian cancer metastasis and modulates cell invasion.

BACKGROUND: Although metastatic disease is the primary cause of death from epithelial ovarian carcinoma, to the authors' knowledge the cellular mechanisms that regulate intraperitoneal metastasis are largely unknown. Metastasizing ovarian carcinoma cells encounter a collagen-rich microenvironment because the submesothelial matrix is comprised mainly of interstitial collagens Types I and III. METHODS: Immunohistochemistry using primary and metastatic ovarian carcinoma samples was employed to detect expression of Wilms tumor gene protein 1 (WT1). Three-dimensional (3D) collagen culture, real-time reverse transcriptase-polymerase chain reaction, and immunofluorescent staining were used to evaluate changes in WT1 RNA and protein expression in response to 3D collagen culture. Boyden chamber invasion assay, scratch-wound motility assay, and Western blot analysis were used to establish the function of WT1 in ovarian carcinoma cells. RESULTS: To model intraperitoneal invasion in vitro, ovarian cancer cells were cultured in a 3D collagen microenvironment. 3D collagen culture resulted in robust induction of WT1 at the mRNA and protein levels. WT1 expression was prevalent in primary ovarian tumors and was retained in paired peritoneal metastases. Functional studies supported a role for WT1 in intraperitoneal invasion, because siRNA knockdown of WT1 expression reduced the ability of ovarian cancer cells to invade 3D collagen gels. CONCLUSIONS: The data from the current study identify a novel regulatory mechanism for the control of WT1 expression and provide evidence for a functional role of WT1 protein in the control of cellular invasive activity.

Vimentin reactivity in renal oncocytoma: immunohistochemical study of 234 cases.

CONTEXT: The expression of vimentin in benign renal oncocytomas has been controversial. However, this is of clinical significance because immunostains may be used in differential diagnosis of renal tumors on limited biopsy specimens. Using different staining and analysis methods, we studied vimentin immunoreactivity in a large series of renal oncocytomas with a special emphasis on the immunoreactivity patterns. OBJECTIVE: Immunohistochemical expression of vimentin has been used in the differential diagnosis of renal epithelial neoplasms. Although typically expressed in most renal cell carcinomas, the immunoreactivity of this intermediate filament in renal oncocytomas has been controversial. DESIGN: We studied vimentin immunoreactivity in a large series of 234 renal oncocytomas using 2 staining methods as well as manual and automated imaging analyses. RESULTS: We found that the focal vimentin immunoreactivity can be seen in most (72.6%) renal oncocytomas with vimentin-positive tumor cells usually found in the edge of a central scar or in small clusters scattered throughout the tumor. Computer-aided imaging analysis using ChromaVision Automatic Cellular Imaging System II confirmed the difference in vimentin immunoreactivity between oncocytoma and other renal neoplasms. CONCLUSIONS: Our study of vimentin immunohistochemistry in a series of renal oncocytomas, which to our knowledge is the largest ever published, showed focal vimentin positivity detected in most oncocytomas. Because the vimentin staining patterns in renal oncocytomas are different from those seen in clear cell or papillary renal cell carcinomas, we consider vimentin staining to be helpful in the differential diagnosis of oncocytoma from other renal tumor mimics. Furthermore, strong vimentin positivity in a renal cell neoplasm does not exclude the diagnosis of renal oncocytoma, particularly in a limited biopsy specimen.

Surgical considerations for the management and resection of esophageal gastrointestinal stromal tumors.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are the most common sarcoma of the gastrointestinal tract, but occur rarely in the esophagus. Use of tyrosine kinase inhibitors has revolutionized therapy for GISTs but complete resection remains the treatment of choice. Esophageal GISTs require special consideration regarding perioperative treatment, evaluation, and conduct of operation. METHODS: We report our experience (from 2000 to 2003) with four patients who underwent resection of esophageal GIST, reviewed consensus management guidelines, and performed a literature review for reported cases. Query of the National Cancer Database was made to assess national experience with esophageal GISTs. RESULTS: All four patients had esophageal GISTs successfully differentiated from leiomyomata by immunohistochemistry on fine needle aspirates obtained during endoscopic ultrasound. At the time of resection all tumors were noted to be adherent to tissues other than submucosa that required resection of esophageal muscularis, periesophageal tissue, or mucosa. All patients were thought to have complete resection and were alive at last contact (median, 33 months). Two of four patients recurred, one of whom underwent esophagectomy; the other patient is alive on imatinib. Seven case reports with median follow-up of three years reported no recurrence with either enucleation or esophagectomy. The National Cancer Database contains 33 cases of esophageal GIST reported since 1999. Nine of 24 patients died within six months of diagnosis. CONCLUSIONS: Esophagectomy is the treatment of choice for esophageal GISTs but requires attention to operative details that emphasize complete en bloc excision of surrounding tissue. Preoperative imatinib may improve resectability.

Engagement of collagen-binding integrins promotes matrix metalloproteinase-9-dependent E-cadherin ectodomain shedding in ovarian carcinoma cells.

Reversible modulation of cell-cell adhesion, cell-matrix adhesion, and proteolytic activity plays a critical role in remodeling of the neoplastic ovarian epithelium during metastasis, implicating cadherins, integrins, and proteinases in i.p. metastatic dissemination of epithelial ovarian carcinoma (EOC). Aberrant epithelial differentiation is an early event in ovarian carcinogenesis; thus, in contrast to most carcinomas that lose E-cadherin expression with progression, E-cadherin is abundant in primary EOC. Metastasizing EOCs engage in integrin-mediated adhesion to submesothelial interstitial collagens and express matrix metalloproteinases (MMP) that facilitate collagen invasion, thereby anchoring secondary lesions in the submesothelial matrix. As metalloproteinases have also been implicated in E-cadherin ectodomain shedding, the current study was undertaken to model the effects of matrix-induced integrin clustering on proteinase-catalyzed E-cadherin ectodomain shedding. Aggregation of collagen-binding integrins induced shedding of an 80-kDa E-cadherin ectodomain [soluble E-cadherin (sE-cad)] in a MMP- and Src kinase-dependent manner, and sE-cad was prevalent in ascites from ovarian cancer patients. Expression of MMP-9 was elevated by integrin aggregation, integrin-mediated ectodomain shedding was inhibited by a MMP-9 function blocking antibody, and incubation of cells with exogenous MMP-9 catalyzed E-cadherin ectodomain shedding. In contrast to other tumors wherein sE-cad is released into the circulation, EOC tumors maintain direct contact with sE-cad-rich ascites at high concentration, and incubation of EOC cells with physiologically relevant concentrations of recombinant sE-cad disrupted adherens junctions. These data support a novel mechanism for posttranslational modification of E-cadherin function via MMP-9 induction initiated by cell-matrix contact and suggest a mechanism for promotion of EOC metastatic dissemination.

Microenvironmental regulation of membrane type 1 matrix metalloproteinase activity in ovarian carcinoma cells via collagen-induced EGR1 expression.

Late stage ovarian cancer is characterized by disseminated intraperitoneal metastasis as secondary lesions anchor in the type I and III collagen-rich submesothelial matrix. Ovarian carcinoma cells preferentially adhere to interstitial collagen, and collagen-induced integrin clustering up-regulates the expression of the transmembrane collagenase membrane type 1 matrix metalloproteinase (MT1-MMP). Collagenolytic activity is important in intraperitoneal metastasis, potentiating invasion through the mesothelial cell layer and colonization of the submesothelial collagen-rich matrix. The objective of this study was to elucidate a potential mechanistic link between collagen adhesion and MT1-MMP expression. Our results indicate that culturing cells on three-dimensional collagen gels, but not thin layer collagen or synthetic three-dimensional hydrogels, results in rapid induction of the transcription factor EGR1. Integrin signaling through a SRC kinase-dependent pathway is necessary for EGR1 induction. Silencing of EGR1 expression using small interfering RNA abrogated collagen-induced MT1-MMP expression and inhibited cellular invasion of three-dimensional collagen gels. These data support a model for intraperitoneal metastasis wherein collagen adhesion and clustering of collagen binding integrins activates integrin-mediated signaling via SRC kinases to induce expression of EGR1, resulting in transcriptional activation of the MT1-MMP promoter and subsequent MT1-MMP-catalyzed collagen invasion. This model highlights the role of unique interactions between ovarian carcinoma cells and interstitial collagens in the ovarian tumor microenvironment in inducing gene expression changes that potentiate intraperitoneal metastatic progression.

Birt-Hogg-Dubé syndrome: clinicopathologic findings and genetic alterations.

CONTEXT: Birt-Hogg-Dubé (BHD) syndrome is a rare clinicopathologic condition transmitted in an autosomal dominant fashion. This complex entity is characterized by cutaneous fibrofolliculomas, kidney tumors, pulmonary cysts, and spontaneous pneumothorax. Recently, the gene possibly responsible for the clinical manifestations of BHD syndrome has been cloned and characterized. The few reviews of BHD syndrome found in the English literature mostly focus on the skin lesions or genetics, with limited information on other pathologic changes, particularly the kidney lesions. OBJECTIVE: To review the literature on this subject with a special emphasis on BHD syndrome-associated renal pathology as well as recent advances in molecular genetic discovery of the BHD syndrome. DATA SOURCES: We used all data available after performing a literature search using MEDLINE and searching under the headings "Birt-Hogg-Dubé," "hybrid oncocytic tumors," and "folliculin." CONCLUSIONS: The presence of BHD syndrome should be investigated in any patient with multiple bilateral kidney tumors, especially if the predominant histologic type is chromophobe renal cell carcinoma or the so-called hybrid oncocytic tumor. The genetic alteration for BHD syndrome has been mapped to chromosome 17p12q11, and the gene in this region has been cloned and believed to be responsible for the BHD syndrome. The function of the BHD product, called folliculin, is still unknown, although it is speculated to be a tumor suppressor gene. Numerous mutations have been described in the BHD gene. Studies are ongoing to determine the relationship between the BHD gene and development of sporadic renal cell carcinoma and other lesions.

Urothelial-Type adenocarcinoma of the prostate mimicking metastatic colorectal adenocarcinoma

Adenocarcinoma arising in urinary bladder or prostatic urethra is uncommon. When they occur, the tumor can be mistaken for metastatic lesions, especially from the colon. Here we report the fifth case of a primary urothelial-type adenocarcinoma arising in the prostate which showed enteric differentiation. The patient was a 55 year-old male whose prostatic needle core biopsy showed a high grade adenocarcinoma which was initially thought to be metastatic colon cancer. A follow-up colonoscopy was unremarkable. Subsequent prostatectomy revealed a high grade adenocarcinoma which was positive for cytokeratins 7 and 20, carcinoembryonic antigen, CDX2, and high molecular weight cytokeratin, and negative for prostate specific antigen, prostate specific acid phosphatase and AMACR. A diagnosis of urothelial-type adenocarcinoma of the prostate was rendered. We review the literature regarding this entity, and discuss the differential diagnosis, emphasizing utility of immunohistochemistry in making the diagnosis. Finally, we speculate on the behavior of these rare tumors.

Alpha-methylacyl coenzyme A racemase immunoreactivity in partial atrophy of the prostate.

It was reported that 15 of 19 consultation cases of prostatic partial atrophy were a-methylacyl coenzyme A racemase (AMACR)-positive. We investigated partial atrophy cases from a single institution using a standard AMACR immunostaining method. Immunohistochemical analysis was performed using an antibody cocktail containing p63, high-molecular-weight keratin (34bE12), and AMACR antibodies on 122 foci of partial atrophy. AMACR staining was analyzed in partial atrophy (n = 122) and compared with adjacent benign glands (n = 122) and prostatic carcinomas (n = 28). Of 122 foci of partial atrophy, 38 (31.1%) showed AMACR immunoreactivity. Typically, AMACR staining was weak or moderate. In addition, 82 (67.2%) showed patchy to negative distribution of basal cells. Partial atrophy may show AMACR immunoreactivity when using a 34bE12, p63, and AMACR antibody cocktail staining method. Compounding this problem, focal lack of basal cells may be seen. However, the AMACR staining pattern of partial atrophy is usually comparable to that of adjacent benign glands and substantially different from adenocarcinoma.

Cytologic and histologic findings in multiple renal hybrid oncocytic tumors in a patient with Birt-Hogg-Dubé syndrome: a case report.

BACKGROUND: Birt-Hogg-Dubé (BHD) syndrome is a rare autosomal dominant neoplastic syndrome characterized by multiple skin lesions, lung cysts and renal tumors. A variety of histologic types of renal tumors have been reported, including clear cell renal cell carcinoma (RCC), papillary RCC, chromophobe RCC, oncocytoma and a recently described hybrid oncocytic tumor, which is thought to be highly associated with BHD. CASE: We report a case of a 48-year-old woman with BHD who initially presented to our institution with spontaneous pneumothorax and was found to have multiple lung cysts and renal tumors on computed tomography. We describe the fine needle aspiration findings of one of the renal tumors, which was suggestive of so-called hybrid oncocytic tumor. We also describe the gross and histologic findings of the multiple kidney tumors that the patient subsequently had excised. CONCLUSION: When multiple kidney tumors from a single patient appear oncycytic on fine needle aspiration, especially when focal clear cells are present, the possibility of oncocytomas and hybrid tumors associated with BHD must be entertained.