Primary malignant melanoma of the transverse colon: report of a case and review of the literature

Gastrointestinal involvement by malignant melanoma is predominantly a metastatic phenomenon. Although primary malignant melanoma of the gastrointestinal tract has been documented in the esophagus, stomach, small bowel, and anorectum, the incidence of primary melanoma of the colon is rare and remains controversial in most cases. We present a case of solitary malignant melanoma of the transverse colon occurring in a 64-year-old African American male patient. Complete dermatologic and ophthalmologic examinations revealed no evidence of a cutaneous or an ocular primary lesion. Microscopic examination of the resection specimen revealed malignant melanoma, which was confirmed by immunohistochemical positivity for S100 and melan-A. We believe that this tumor represents a primary colonic malignant melanoma.     

Extranodal interdigitating dendritic cell sarcoma presenting in the pleura: a case report

Interdigitating dendritic cell sarcoma (IDCS) is an extremely rare neoplasm arising from the antigen-presenting cells of the immune system. This disease usually involves the lymph nodes, and rarely, extranodal sites may be affected. The authors report a case of extranodal IDCS presenting in the pleura. A 32-yr-old man presented with progressive chest pain. Imaging studies showed diffuse pleural thickening with pleural effusion. Morphological and immunohistochemical analysis of an incisional biopsy of the pleura were consistent with a diagnosis of IDCS; tumor cells were positive for S100 and CD45, but negative for CD1a, CD21, CD35, B cell and T cell markers. The patient was administered chemotherapy, but died of progressive disease. Although its incidence is extremely rare, this case suggests that extranodal IDCS should be considered in the differential diagnosis of undifferentiated neoplasms and that immunohistochemical staining be performed using appropriate markers.     

Diffuse filiform polyposis with unique histology mimicking familial adenomatous polyposis in a patient without inflammatory bowel disease

Filiform polyposis is an uncommon entity that is most often encountered in the colon of patients with a history of inflammatory bowel disease (IBD). Filiform polyposis is characterized by a large number of "wormlike" polyps lined by histologically normal colonic mucosa. These polyps can mimic adenomatous polyps. Only rare cases without a history or evidence of IBD have been reported. Neuromuscular and vascular hamartoma of the small bowel is a rare, focal disorder characterized by disorganized smooth muscle fascicles throughout the submucosa accompanied by fibrosis, nerve fibers, ganglion cells, and vessels. To our knowledge, there is only one report of this lesion in the large bowel (cecum), where it presented as a mass. Here we report the case of a 50-year-old man with no known history or symptoms of IBD presenting with filiform polyposis involving the entire colon, clinically mimicking familial adenomatous polyposis, and showing histologic features similar to neuromuscular and vascular hamartoma of the small bowel.     

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma without mediastinal disease: mimicking nodular sclerosis classical Hodgkin lymphoma

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma (BCLu-DLBCL/CHL), also known as gray-zone lymphoma, has overlapping clinical and biological characteristics of both diffuse large B-cell lymphoma and classical Hodgkin lymphoma (CHL). These lymphomas are typically associated with mediastinal disease, and extranodal involvement is rare. In the present report, we describe a case of a 78-year-old woman with BCLu-DLBCL/CHL found to have extranodal lesions and no evidence of mediastinal disease. Although biopsy specimens were histologically similar to nodular sclerosis CHL, the tumor cells were positive for CD30 and mature B-cell markers, such as CD20, CD79a, PAX5, BOB.1, and OCT-2, but negative for CD15. Furthermore, the patient had extranodal lesions and an increased level of soluble IL-2 receptor. These findings are unusual in CHL. Therefore, we diagnosed the patient with BCLu-DLBCL/CHL. She received adriamycin, bleomycin, vincristine, and dacarbazine therapy and exhibited partial response. Some cases without mediastinal disease, such as our case, have been reported; however, these cases are rare and further studies are required.     

Primary gastroesophageal-ileal hodgkin lymphoma

Primary Hodgkin lymphoma of the gastrointestinal tract is exceedingly rare to the point that some authors regard with skepticism the existence of this entity. Cases of gastrointestinal Hodgkin lymphoma have been reported previously; however, most of these cases represented secondary involvement of the digestive tract in the context of systemic disease. Other cases have been reclassified in retrospective studies as non-Hodgkin lymphomas after the application of immunohistochemical techniques. We report a case of primary Hodgkin lymphoma of the gastrointestinal tract in a patient who presented with obstructive symptoms at the site of a gastroileal bypass; the bypass had been performed years earlier because of morbid obesity. Some non-Hodgkin lymphomas may morphologically mimic Hodgkin lymphoma and vice versa; therefore, an accurate pathologic diagnosis is important, since the therapeutic approach and prognostic implications differ significantly for these diseases. In this context, immunohistochemistry should be used to confirm or to exclude the histologic diagnosis of Hodgkin lymphoma.     

Classical Hodgkin lymphoma arising in the rectum

We report a case of an 81-year-old immunocompetent Mexican man who underwent an abdominal-perineal rectal resection for a mass clinically thought to be carcinoma. Histopathologic diagnosis revealed classical Hodgkin lymphoma, nodular sclerosis type, involving the rectum. The diagnosis was confirmed by immunohistochemical studies that showed that the neoplastic cells were positive for CD15 and CD30 and negative for CD45 (LCA). In situ hybridization for Epstein-Barr virus small-encoded RNA was also positive in the neoplastic cells. Hodgkin lymphoma arising in the rectum of immunocompetent patients is rare, with only 12 cases (including this one) reported in the literature. Of these, the diagnosis was confirmed by immunohistochemical studies in only two cases, and this is the first case assessed and shown to be positive for Epstein-Barr virus.     

Clinical characteristics of 26 patients with primary extranodal Hodgkin lymphoma

Background: Most Hodgkin lymphoma (HL) patients present with disease in nodal regions. However, in a small subset, disease develops extranodal sites primarily, such as lung and liver. This study aims to identify the characteristics and outcomes of patients with primary extranodal HL. Methods: A retrospective analysis of patients with HL from 1998 to 2012 was enrolled. We selected 26 HL patients with primary extranodal involvement from 251 previously untreated HL patients. All data analyses were performed with SPSS software version 17.0 and GraphPad Prism 5. Results: We identified 26 patients with primary extranodal HL. Results in the series of young patients, male predominated. Pathologically, the major pathologic types were nodular sclerosis classical HL (NSCHL, 46.2%) and mixed cellularity classical HL (MCCHL, 38.5%). Thirteen patients had early stage (I or II stage). The most commonly primarily extranodal sites were the lung and the stomach and intestine, followed by the liver and bones. Fifteen of 26 received chemotherapy alone and 11 received combination therapy. Finally, primary extranodal HLs in our study have a favorable survival. Furthermore, there was no significant association between the international prognostic score (IPS) and survival in patients with extranodal HL. Conclusion: Our retrospective data in part reflect clinical characteristics of primary extranodal HL in China, and form the basis for further concerning researches.     

Colonic adenocarcinoma presenting as a cutaneous metastasis in an old operative scar

Cutaneous metastasis from colon cancer is an uncommon event that usually occurs after identification of the primary tumour and generally indicates diffuse disease. Incisional metastasis occasionally occurs following laparoscopic or open colon cancer resection. However, to the authors' knowledge only one previous case of colon cancer presenting as a cutaneous metastasis in an old operative scar has been reported. We describe a case of colon cancer presenting as a cutaneous metastasis in an old cholecystectomy scar and discuss possible pathophysiological mechanisms.     

Primary Epstein-Barr virus-associated Hodgkin disease of the ileum complicating Crohn disease

We describe a case of primary Hodgkin disease of the terminal ileum in a 38-year-old man with Crohn disease of 24 years' duration. The infiltrate was located in an ulcerated fistula involving the terminal ileum and urinary bladder. Reed-Sternberg cells and their variants were characteristically positive for CD15, fascin, and CD30 and showed focal positivity for CD20. Epstein-Barr virus messenger RNA was also detected in the neoplastic cells. Staging revealed no evidence of other lymph node or organ involvement. Although rare, primary gastrointestinal Hodgkin disease arising in the setting of Crohn disease may have a stronger association with Epstein-Barr virus infection than conventional Hodgkin disease.     

Testicular natural killer/t-cell lymphoma,nasal type,of true natural killer-cell origin

The majority of primary testicular lymphomas are of B-cell type. Other primary lymphomas are rarely encountered in the testes. Natural killer (NK)/T-cell lymphomas of nasal type are aggressive extranodal lymphomas associated with Epstein-Barr virus infection that are usually encountered in the upper aerodigestive tract. They also occur in the skin, soft tissue, and colon. Primary testicular NK/T-cell lymphomas are rarely reported. We describe the case of a 66-year-old Korean man who presented with right-sided painless testicular enlargement and underwent radical orchiectomy. Histologic examination revealed an angiocentric and angioinvasive infiltrate of medium to large tumor cells with moderately abundant pale pink cytoplasm and folded and indented pleomorphic nuclei. Paraffin immunohistochemical studies showed positivity of the tumor cells for CD45, TIA-1, granzyme B, CD56, and CD3 epsilon. In situ hybridization showed diffuse positivity for Epstein-Barr virus-encoding RNA. The results of gene rearrangement studies for the gamma chain of the T-cell receptor were negative. The results of paraffin immunohistochemical studies for CD20, CD8, CD45RO, beta f1, and ALK-1 were negative. An extensive workup showed no evidence of lymphoma outside the testes. We report a rare case of primary testicular NK/T-cell lymphoma of the nasal type of true NK-cell origin.     

Nonsecretory variant of immunoproliferative small intestinal disease: a case report with pathologic, immunophenotypic, and molecular findings

We report a case of the nonsecretory variant of immunoproliferative small intestinal disease involving the distal small bowel and the mesenteric and retroperitoneal lymph nodes in a 19-year-old woman from Mexico. This variant extranodal marginal zone B-cell lymphoma appeared similar in the different sites of involvement, with more interspersed large cells and greater plasmacytic differentiation present in intestinal specimens. Characteristic lymphoepithelial lesions and follicular colonization were seen in intestinal and lymph node sections, respectively. The neoplastic B cells were cytoplasmic immunoglobulin (Ig) A heavy-chain restricted and lacked surface and cytoplasmic light-chain expression by flow cytometric analysis. Serum and urine protein electrophoresis/immunofixation revealed hypogammaglobulinemia with no paraprotein. Molecular studies showed absence of immunoglobulin heavy-chain (IgH) gene rearrangement, with a nonfunctional clonotypic rearrangement of the kappa light-chain gene. This case highlights the role for kappa light-chain gene evaluation in immunoproliferative small intestinal disease, because IgH gene rearrangement analysis is often negative.     

T cell/histiocyte-rich large B-cell lymphoma: an update on its biology and classification

T cell/histiocyte-rich large B-cell lymphoma (THRLBCL), originally considered an uncommon variant of Diffuse Large B-Cell Lymphoma (DLBCL), is recognized by the World Health Organisation as a separate clinicopathological entity since 2008. It predominantly affects middle aged men often presenting with advanced stage disease frequently involving spleen, liver and bone marrow at time of diagnosis. According to the WHO, this lymphoma is morphologically characterized by less than 10% of large neoplastic B cells in a background of abundant T cells and frequently histiocytes. Differentiating THRLBCL from other lymphoproliferative disorders such as Nodular Lymphocyte Predominant Hodgkin Lymphoma (NLPHL) and Lymphocyte-Rich classical Hodgkin lymphoma (LRcHL) is important from a clinical point of view and can be achieved in most cases, given adequate biopsy specimens, by careful morphological and immunohistochemical evaluation of both the neoplastic cells as well as the nonneoplastic stromal component. According to this WHO definition, THRLBCL is still considered a clinically heterogeneous entity, though it is noted that especially the cases containing numerous histiocytes behave aggressively and show resistance to current therapies for DLBCL. Gene expression profiling studies of THRLBCL provided evidence for a prominent role for this histiocytic component that is important for a tolerogenic host immune response in which they may assist neoplastic cells in escaping the T cell-mediated immune surveillance. Therefore, reserving the diagnosis of THRLBCL to cases containing a large proportion of histiocytes might be relevant, as modulating their activity could provide new therapeutic options.     

Follicular lymphoma of the gallbladder and extrahepatic bile ducts

We report a case of a 63-year-old female, who presented with symptoms and signs of an acute biliary tract obstruction with jaundice and pain. Ultrasound together with intraoperative examination suggested a Klatskin tumour. Following radical resection, a tumour located predominantly in the wall of gallbladder, but infiltrating extensively also the walls of cystic, common hepatic and choledochus duct, was found. On the basis of cell morphology and the results of immunohistochemical analysis, the tumour was classified as an extranodal follicular lymphoma, grade II of the gallbladder, involving also hilar extrahepatic bile ducts. To the best of our knowledge, this is the first report of an extranodal follicular lymphoma in this location. A postoperative follow-up of more than 3 years has been completely uneventful without any symptoms or signs of disease recurrence.     

Extranodal lymphoplasmacytoid lymphoma (immunocytoma) presenting as small intestinal obstruction

A 57-year-old woman presented with intermittent symptoms of intestinal obstruction. Workup provided nondiagnostic radiologic studies. An exploratory laparotomy revealed a segmental dilatation in the proximal ileum, which showed diffuse thickening of the intestinal wall. Microscopic examination of the affected area disclosed a diffuse transmural infiltrate composed of small lymphocytes, mature plasma cells, and lymphoplasmacytoid cells in different stages of maturation associated with extracellular periodic acid-Schiff-positive material. In addition, serum protein electrophoresis showed a monoclonal immunoglobulin M kappa paraprotein. Postoperative workup did not demonstrate evidence of systemic involvement. The morphologic features and immunohistochemical and molecular analyses were consistent with lymphoplasmacytoid lymphoma (immunocytoma). We report an unusual case of primary extranodal immunocytoma involving the small intestine and discuss its clinicopathologic features.     

Primary Hodgkin lymphoma of the stomach--a case report

A case of a 69-year-old male with a one-month history or recurrent attacks of GI bleeding, secondary anemic syndrome and epigastric pain is reported. Endoscopic examination revealed a tumorous lesion suspicious of malignancy. Neither lymphadenopathy nor any other tumorous lesion was identified by extensive clinical examination. In the biopsy specimens there was ulcerated gastric mucosa with an infiltration by lymphoid cells, predominantly of mature T-cell type. Atypical large cells with large nuclei with prominent nucleoli were dispersed among the mature lymphocytes. These atypical cells were both mono- and binucleated (Hodgkin and RS cells). Both cell types revealed immunohistochemically membranous and dot-like perinuclear positivity of CD30 and CD15 antigens. Based on morphologic features and immunohistochemical findings, a diagnosis of primary gastric Hodgkin lymphoma was established. Diagnostic approach, as well as differential diagnosis of primary Hodgkin lymphoma in this extremely rare location, are discussed.     

Fine-needle aspiration of extranodal and extramedullary hematopoietic malignancies

There is relatively little information concerning the use of fine-needle aspiration (FNA) to diagnose extranodal and extramedullary hematopoietic malignancies. Seventy-one such cases diagnosed by FNA form the basis of this study. Seventy-one cases of FNAs performed between 1988 and 1998 on extranodal and extramedullary hematopoietic malignancies were reviewed in order to evaluate the usefulness of this technique in diagnosing these entities as well as to assess patterns of relapse. There were 45 male and 26 female patients ranging in age from 29-86 years (mean, 68 years). Sixty-six patients had a previous history of a hematopoietic malignancy. Aspirates from 65 of these patients were consistent with the patient's known primary. One aspirate of a paravertebral mass from a multiple myeloma patient showed extramedullary hematopoiesis. The remaining five aspirates were cases of multiple myeloma that first presented as soft tissue masses. The most common malignancies were lymphoma: 52 cases (73%), 48 large cell lymphomas, four mixed small and large cell lymphoma; followed by multiple myeloma: 12 cases (17%); leukemia: four cases (5.4%); Hodgkin disease: two cases (2.8%); and one case of extramedullary hematopoiesis. The aspirate sites were soft tissue: 23 cases (32%); bone: 17 cases (24%); kidney: 14 cases (20%); liver: 11 cases (15%); lung: three cases (4%); adrenal: two cases (3%); and eye: one case. The interval between primary diagnosis and FNA was 1-36 months (mean, 13 months). In conclusion, 98% of the aspirates were neoplastic in patients with a known history of hematopoietic malignancies. The most common site of involvement was soft tissue in 23 (32%) cases. In five patients with multiple myeloma, the FNA diagnosis prompted a work-up to find the primary site of involvement. FNA is a useful technique in assessing extranodal and extramedullary hematopoietic malignancies.     

Isoliert extranodale Rosai-Dorfman-Erkrankung

A case of extranodal sinus histiocytosis with massive lymphadenopathy (ENSHML; Rosai-Dorfman disease) is reported. The patient presented with a history of intracranial tumour and exophthalmus. Clinical examination found a large mass in the left orbit and paranasal sinuses. Excisional biopsy showed a dense fibrous tissue with an infiltrate rich in macrophages. Further evaluation revealed a retroperitoneal mass with consecutive ureteral stenosis. Further histological and immunohistochemical investigation of the orbital mass, now in suspicion of a systemic disease showed an infiltrate of S-100-positive histiocytes and emperipolesis allowing the diagnosis of extranodal sinus histiocytosis. The correct histologic diagnosis was delayed due to the unusual and isolated extranodal localisation of the disease. The literature concerning extranodal manifestations of Rosai-Dorfman disease is reviewed. We suggest the additional evaluation of such rare and unusual cases in experienced reference centers.     

Small bowel adenocarcinoma with high levels of microsatellite instability in Crohn's disease

Microsatellite instability (MSI) is a hallmark of carcinomas occurring in the setting of hereditary nonpolyposis colorectal cancer, but can also be found in sporadic and colitis-associated tumors. The incidence of MSI in Crohn's disease is unknown and has usually been reported in the colon. We report the case of a 26-year-old man, diagnosed 4 years earlier with Crohn's disease, who developed an associated small bowel adenocarcinoma. The tumor was found to have high levels of MSI by immunohistochemical staining and by MSI testing. No mutations were identified by genetic testing, and high levels of MSI are most probably due to hypermethylation.     

Thyroid sclerosing mucoepidermoid carcinoma with eosinophilia: mimic of Hodgkin disease in nodal metastases

We present the clinical and pathologic findings of a case of sclerosing mucoepidermoid carcinoma with eosinophilia of the thyroid in a 39-year-old woman. This particular case is notable because it initially presented as a cervical lymph node metastasis, and the initial clinical and histologic impression was Hodgkin disease, nodular sclerosis type. Sclerosing mucoepidermoid carcinoma with eosinophilia is a differentiated malignant neoplasm of the thyroid that can be confused with anaplastic carcinoma, medullary carcinoma, squamous cell carcinoma, or, as in this case, Hodgkin disease. A correct diagnosis of sclerosing mucoepidermoid carcinoma with eosinophilia involves awareness of this entity and appropriate immunohistochemical analysis. In this article, we briefly review the literature and stress the histologic and cytologic findings characteristic of sclerosing mucoepidermoid with eosinophilia of the thyroid.     

Vesico-ileosigmoidal fistula caused by diverticulitis: report of a case and literature review in Japan

Enterovesical fistula is a relatively uncommon complication of colorectal and pelvic malignancies, diverticulitis, inflammatory bowel disease, radiotherapy, and trauma in Asian countries. A case of vesico-ileosigmoidal fistula and a literature review of this disease in Japan are presented. A 70-yr-old male was referred with complaints of urinary pain and pneumaturia. On admission, urinary tract infection and pneumaturia were presented. A barium enema demonstrated multiple diverticulum in his sigmoid colon and the passage of contrast medium into the bladder and ileum. Under the diagnosis of vesico-ileosigmoidal fistula due to suspected diverticulitis of the sigmoid colon, sigmoidectomy and partial resection of the ileum with partial cystectomy were performed. The histopathology revealed diverticulosis of the sigmoid colon with diverticulitis and development of a vesico-ileosigmoidal fistula. No malignant findings were observed. Until the year 2000, a total of 173 cases of vesico-sigmoidal fistula caused by diverticulitis had been reported in Japan. Pneumaturia and fecaluria are the most common types, presenting symptoms in 63% of the cases. Computed tomography, with a sensitivity of 40% to 100%, is the most commonly used diagnostic study. For patients with vesico-sigmoidal fistula, resection of the diseased sigmoid colon and partial cystectomy with primary anastomosis are the safest and most acceptable procedures, leading to the best results.