Case Reports in Pathology The latest articles from Hindawi Publishing Corporation © 2014 , Hindawi Publishing Corporation . All rights reserved. Unusual Dermoid Cyst in Oral Cavity Thu, 10 Apr 2014 12:08:38 +0000 Dermoid cysts in oral cavity are unusual lesions. Their etiology is not yet clear and can be associated with trapped cells as a result of the inclusion error resulting in the development into the ectoderm, mesoderm, and endoderm tissues. The aim of this case report is to evidence the presence of a dermoid cyst in the floor of mouth surgically removed. In the present case, the lesion showed soft consistency, floating, regular borders, smooth surface, and the same color as the adjacent mucosa, asymptomatic and measuring 4.5 × 5.5 cm in its greatest diameter. The initial diagnostic was ranula in consequence of the similarity with clinical characteristics and localization. After surgical removal lesion, a fibrotic capsule was identified with a friable material with intensive yellow color. The microscopic exam showed cystic lesion with cavity lined by squamous stratified epithelium hyperorthokeratinized. Cutaneous attachments, such as sebaceous glands and hair follicles, were present in connective adjacent tissue. Surgical intervention is elective in these situations. All dentists must have a thorough knowledge of this unusual lesion. Evanice Menezes Marçal Vieira, Alvaro Henrique Borges, Luis Evaristo Ricci Volpato, Alessandra Nogueira Porto, Artur Aburad Carvalhosa, Gilberto de Almeida Botelho, and Matheus Coelho Bandeca Copyright © 2014 Evanice Menezes Marçal Vieira et al. All rights reserved. HPV11 Positive Endometrioid Carcinoma of the Endometrium with Signet-Ring Cells: Diagnostic Criteria and Review of the Literature Mon, 07 Apr 2014 15:40:27 +0000 The presence of signet-ring cells in an endometrial adenocarcinoma is extremely uncommon and it is always necessary to rule out a metastatic neoplasm. We report a FIGO grade 2 endometrial carcinoma with a signet-ring cell component found in the curettage performed to a 53-year-old woman. The neoplastic proliferation was also found in the endometrium of the radical hysterectomy with bilateral salpingo-oophorectomy and pelvic and para-aortic lymphadenectomy. The uterine neoplasm invaded less than one-half of the myometrium (FIGO stage I B). Alcian blue showed the presence of mucin in the signet-ring cells. The patient was alive and without evidence of recurrence 14 months after surgery. Polymerase chain reaction method from paraffin-embedded tissue revealed the presence of human papilloma virus type 11. We have discussed the differential diagnosis of this kind of neoplasm and we have reviewed the literature on signet-ring cell carcinoma of the endometrium. Teresa Pusiol Copyright © 2014 Teresa Pusiol. All rights reserved. Mixed Large Cell Neuroendocrine Carcinoma and Adenocarcinoma with Spindle Cell and Clear Cell Features in the Extrahepatic Bile Duct Tue, 01 Apr 2014 09:05:51 +0000 Mixed adenoneuroendocrine carcinomas, spindle cell carcinomas, and clear cell carcinomas are all rare tumors in the biliary tract. We present the first case, to our knowledge, of an extrahepatic bile duct carcinoma composed of all three types. A 65-year-old man with prior cholecystectomy presented with painless jaundice, vomiting, and weight loss. CA19-9 and alpha-fetoprotein (AFP) were elevated. Cholangioscopy revealed a friable mass extending from the middle of the common bile duct to the common hepatic duct. A bile duct excision was performed. Gross examination revealed a 3.6 cm intraluminal polypoid tumor. Microscopically, the tumor had foci of conventional adenocarcinoma (CK7-positive and CA19-9-postive) surrounded by malignant-appearing spindle cells that were positive for cytokeratins and vimentin. Additionally, there were separate areas of large cell neuroendocrine carcinoma (LCNEC). Foci of clear cell carcinoma merged into both the LCNEC and the adenocarcinoma. Tumor invaded through the bile duct wall with extensive perineural and vascular invasion. Circumferential margins were positive. The patient’s poor performance status precluded adjuvant therapy and he died with recurrent and metastatic disease 5 months after surgery. This is consistent with the reported poor survival rates of biliary mixed adenoneuroendocrine carcinomas. John Wysocki, Rishi Agarwal, Laura Bratton, Jeremy Nguyen, Mandy Crause Weidenhaft, Nathan Shores, and Hillary Z. Kimbrell Copyright © 2014 John Wysocki et al. All rights reserved. Solitary Mastocytoma of the Vulva Sun, 30 Mar 2014 00:00:00 +0000 Solitary mastocytoma of the skin is a rare tumor. Its occurrence in the vulva is extremely rare with only few case reports in the literature. We report a solitary mastocytoma of the vulva in a 10-year-old girl. Her systemic examination was unremarkable. The clinical and histopathological features were consistent with the diagnosis of solitary mastocytoma of the vulva. The follow-up after surgical excision was uneventful. The purpose of this communication is (i) to report a case of solitary mastocytoma occurring in an unusual site, the vulva and to show that (ii) in this case age at presentation is 10 years with infancy as common age of presentation of solitary mastocytoma, and to show that (iii) in appropriate setting this should be included in the differential diagnosis of vulval swelling. Shasi Velusamy, Jayasree Karuthedath Areeppurath Mana, and Chalissery Francis Mathew Copyright © 2014 Shasi Velusamy et al. All rights reserved. Spontaneous Splenic Rupture in Melanoma Wed, 26 Mar 2014 08:27:37 +0000 Spontaneous rupture of spleen due to malignant melanoma is a rare situation, with only a few case reports in the literature. This study reports a previously healthy, 30-year-old man who came with chief complaint of acute abdominal pain to emergency room. On physical examination, abdominal tenderness and guarding were detected to be coincident with hypotension. Ultrasonography revealed mild splenomegaly with moderate free fluid in abdominopelvic cavity. Considering acute abdominal pain and hemodynamic instability, he underwent splenectomy with splenic rupture as the source of bleeding. Histologic examination showed diffuse infiltration by tumor. Immunohistochemical study (positive for S100, HMB45, and vimentin and negative for CK, CD10, CK20, CK7, CD30, LCA, EMA, and chromogranin) confirmed metastatic malignant melanoma. On further questioning, there was a past history of a nasal dark skin lesion which was removed two years ago with no pathologic examination. Spontaneous (nontraumatic) rupture of spleen is an uncommon situation and it happens very rarely due to neoplastic metastasis. Metastasis of malignant melanoma is one of the rare causes of the spontaneous rupture of spleen. Hadi Mirfazaelian, Ahmad Oryan, Aida Davari, Khosrow Daneshbod, and Yahya Daneshbod Copyright © 2014 Hadi Mirfazaelian et al. All rights reserved. Cylindroma with Stromal Adipose Tissue Metaplasia versus Arising in a Background of Nevus Lipomatosus Sun, 16 Mar 2014 11:44:41 +0000 Nevus lipomatosus superficialis is a rare type of connective tissue nevus. Cylindroma is a benign skin appendage tumor with a predilection for the scalp of older females. We describe the case of a 56-year-old woman with a scalp lesion demonstrating histopathologic features consistent with benign cylindroma arising within a nevus lipomatosus superficialis. To our knowledge, this lesion has not been raised in the literature in the differential for cylindroma with what is presumed to be stromal adipose metaplasia. Ryan Yu and Salem Alowami Copyright © 2014 Ryan Yu and Salem Alowami. All rights reserved. Bilateral Spontaneous Pneumothorax in Chronic Silicosis: A Case Report Sun, 16 Mar 2014 00:00:00 +0000 Silicosis is an occupational lung disease caused by inhalation of crystalline silica. People working in occupations like sandblasting, surface drilling, tunneling, silica flour milling, ceramic making, and so forth are predisposed to develop silicosis. Crystalline forms of silica are more fibrogenic than the amorphous forms, highlighting the importance of the physical form in pathogenesis. Lung biopsy is rarely performed for the diagnosis of silicosis as it can easily be detected by occupational history and radiological features. Patients with silicosis can develop complications like tuberculosis, lung cancer, progressive massive fibrosis, cor pulmonale, broncholithiasis, or tracheobronchial compression by lymph nodes. Pleural involvement in silicosis is rare. Spontaneous pneumothorax is a pleural complication that can develop in such patients. Usually in silicosis pneumothorax is unilateral. We hereby report the lung biopsy findings and discuss the mechanism of pneumothorax development in a case of chronic silicosis who, later on died during the course of the disease. Pritinanda Mishra, Sajini Elizabeth Jacob, Debdatta Basu, Manoj Kumar Panigrahi, and Vishnukanth Govindaraj Copyright © 2014 Pritinanda Mishra et al. All rights reserved. Extramedullary Hematopoiesis in Uterine Leiomyoma Associated with Numerous Intravascular Thrombi Thu, 06 Mar 2014 14:09:31 +0000 We report a case of extramedullary hematopoiesis (EMH) in uterine leiomyoma and associated numerous intravascular thrombi. A 29-year-old nulliparous female presented with heavy vaginal bleeding and a hematocrit of 22%. No bone marrow biopsy has been performed. She had a history of uterine leiomyomata and menorrhagia for a year. A transvaginal ultrasound confirmed the presence of a uterine leiomyoma. The patient was treated conservatively with oral contraceptive pills due to desire for fertility. However, she continued to have heavy vaginal bleeding and developed bilateral upper extremity deep vein thrombosis and multiple superficial vein thromboses after two months. An exploratory laparotomy with uterine myomectomy was performed. Gross examination of the specimen revealed a single nodular mass measuring  cm with a white-tan swirling cut surface. Microscopic examination revealed benign smooth muscle consistent with leiomyoma and numerous intravascular thrombi both with areas of EMH. Immunohistochemical stains confirmed the presence of all three benign lineages of hematopoietic cells. Occurrence of EMH in uterine leiomyoma and intravascular thrombi is very rare. It may be related to systemic hematopoietic stimulation due to severe chronic anemia and local presence of hematopoietic growth factors and/or cytokines. Xiaoyan Cui, Deniz Peker, Heather O. Greer, Michael G. Conner, and Lea Novak Copyright © 2014 Xiaoyan Cui et al. All rights reserved. Granulomatous Pancreatitis in a Patient with Acute Manifested Insulin-Dependent Diabetes Mellitus Wed, 05 Mar 2014 00:00:00 +0000 Isolated granulomatous noncaseating pancreatitis is a rare condition exceptionally described in human population. We demonstrate a case of the a 71-years-old female patient suffering from recent diabetes mellitus, generalized atherosclerosis and hypertension who died due to pulmonary embolism and terminal bronchopneumonia. Lipomatosis of pancreatic tissue was observed during the postmortem examination. Histological examination of pancreatic tissue discovered multiple small noncaseating epithelioid cell and giant cell granulomas, partly replacing the islets of Langerhans. To our knowledge, our case represents the first description of noninfectious granulomatous pancreatitis associated with acute manifested insulin-dependent diabetes mellitus. Václav Mandys, Michal Kheck, and Michal Anděl Copyright © 2014 Václav Mandys et al. All rights reserved. Sclerosing Polycystic Adenosis of the Retromolar Pad Area: A Case Report Mon, 03 Mar 2014 13:36:40 +0000 Sclerosing polycystic adenosis is a rare pathological lesion that affects salivary glands. The majority of cases involve the parotid and its occurrence in minor glands is exceedingly rare. Here, we report the first case of this lesion in the retromolar pad area and discuss its histological features and immunohistochemical reactivity with αSMA and Ki67 markers. A review of the literature on its immunohistochemical profile is also provided. Sclerosing polycystic adenosis has a diverse histomorphology and should be differentiated from other more important pathologic lesions. Sepideh Mokhtari, Saede Atarbashi Moghadam, and Abbas Mirafsharieh Copyright © 2014 Sepideh Mokhtari et al. All rights reserved. Idiopathic Infantile Arterial Calcification: A Possible Cause of Refractory Cardiopulmonary Failure in Infancy Sun, 09 Feb 2014 14:18:00 +0000 Idiopathic Infantile Arterial Calcification is a rare autosome recessive disease characterized by extensive calcification of medium and large arteries. Loss-of-function mutations in ectonucleotide pyrophosphatase/phosphodiesterase 1 gene have been described in more than 80% of the cases. Although the diagnosis is usually made at autopsy, it is possible to identify cases based on clinical presentation, radiology findings, and molecular studies. Appropriate treatment can be initiated and has been shown to successfully induce permanent remission. We report a 4-week-old neonate who initially presented with respiratory distress, heart failure, and Coxsackie B viremia suggestive of viral induced cardiomyopathy. His symptoms progressed to multiple organ failure and he eventually expired at four weeks of age. On autopsy, diffuse calcium deposition within the internal elastic lamina of medium and large arteries was identified, as well as narrowing of lumen due to myointimal proliferation. This case report will emphasize the importance of taking this rare curable disease into consideration in all cases of infants with cardiopulmonary failure. A. Nael, P. J. Siaghani, D. Chen, S. G. Romansky, and L. Shane Copyright © 2014 A. Nael et al. All rights reserved. Metastatic Squamous Cell Carcinoma of the Anus to the Lung Confirmed with Allelotyping Sun, 09 Feb 2014 11:55:19 +0000 Histopathologic techniques are insufficient for distinguishing primary squamous cell carcinoma (SCC) from metastatic SCC, which is clinically important. A patient with SCC of the anus was found to also have SCC of the lung, and the question of metastatic versus synchronous primary diseases was raised. Immunohistochemical and hematoxylin and eosin (H&E) staining on sections of tissue could not discriminate between the two entities. Immunostain for p16 and chromogenic in situ hybridization for human papillomavirus (HPV) type 16 were positive in both tumors. Additionally, allelotyping for loss of heterozygosity displayed similar findings and confirmed the histopathological impression of anal SCC metastasis to the lung. The patient was treated with palliative chemotherapy instead of additional surgical treatment. When multiple tumors are present, determining metastatic versus synchronous primary tumors is necessary for appropriate treatment. Identification can be achieved using allelotyping for loss of heterozygosity. Rachel Roth, Susan Moffatt-Bruce, and Marino E. Leon Copyright © 2014 Rachel Roth et al. All rights reserved. Ovarian Basaloid Carcinoma with Shadow Cell Differentiation Mon, 03 Feb 2014 11:44:03 +0000 So-called shadow cell differentiation (SCD) is typical for pilomatrixoma and other skin lesions with follicular differentiation, but it was rarely described also in some visceral carcinomas. We report a case of ovarian basaloid carcinoma with SCD. The tumor presented as a 14 cm ovarian mass in a 45-year-old woman, and therefore the adnexectomy and hysterectomy were performed. The tumor was of high stage. Multiple metastases were found in the liver, retroperitoneal and mediastinal lymph nodes, and the lung. Histologically, the tumor showed a pattern of high-grade basaloid carcinoma with numerous shadow cells. Extensive histologic examination did not reveal any glandular or preexisting teratoma component. Immunohistochemically, the tumor expressed markers of squamous cell differentiation, such as p63, cytokeratin 5/6, and high-molecular-weight keratin. Cytokeratin 7 and CA125 were positive in scattered cells of the lesion. Estrogen and progesterone receptor, vimentin, and p53 were negative. Beta-catenin showed nuclear and cytoplasmic positivity, indicating possible tumor proliferation/differentiation via Wnt signaling pathway. To our knowledge, SCD in basaloid carcinoma of the ovary was not described before. In addition to the description of the case, we review the literature on SCD in visceral carcinomas. Michal Zamecnik, Daniel Jando, and Peter Kascak Copyright © 2014 Michal Zamecnik et al. All rights reserved. Bile Duct Adenoma with Oncocytic Features Tue, 28 Jan 2014 07:24:46 +0000 Bile duct adenomas are benign bile duct proliferations usually encountered as an incidental finding. Oncocytic bile duct neoplasms are rare and the majority are malignant. A 61-year-old male with a diagnosis of colorectal adenocarcinoma was undergoing surgery when a small white nodule was discovered on the surface of the right lobe of his liver. This lesion was composed of cytologically bland cells arranged in tightly packed glands. These cells were immunopositive for cytokeratin 7, negative for Hep Par 1, contained mucin, and had a Ki67 proliferation index of 8%. The morphology, immunophenotype, presence of mucin, and normal appearing bile ducts, as well as the increased Ki67 proliferation rate, were consistent with a bile duct adenoma with oxyphilic (oncocytic) change. Oncocytic tumors in the liver are rare; the first described in 1992. Only two bile duct adenomas with oncocytic change have been reported and neither of them had reported mucin production or the presence of normal appearing bile ducts within the lesion. E. J. Johannesen, Zihao Wu, and Jason-Scott Holly Copyright © 2014 E. J. Johannesen et al. All rights reserved. Brooke-Spiegler Syndrome: A Rare Entity Thu, 23 Jan 2014 08:55:51 +0000 Brooke-Spiegler syndrome is a rare entity. It is an autosomal dominant syndrome in which multiple trichoepitheliomas, cylindromas, or other adnexal tumors are seen. Very few cases of Brooke-Spiegler syndrome are reported in the literature. We came across a 40 -year-old female in which multiple trichoepitheliomas and cylindromas were seen on scalp. In view of clinical history and histopathological examination it was diagnosed as Brooke-Spiegler syndrome. We report this case because of its rarity. Monika Rathi, Seema Awasthi, Satish Kumar Budania, Faiyaz Ahmad, Shyamoli Dutta, and Ashutosh Kumar Copyright © 2014 Monika Rathi et al. All rights reserved. Role of Fine Needle Aspiration in the Diagnosis of the Rare Disease of Langerhans Cell Histiocytosis in a Child Wed, 22 Jan 2014 16:03:51 +0000 Langerhan’s cell histiocytosis (LCH) results from the proliferation of immunophenotypically and functionally immature, morphologically rounded Langerhan’s cells along with eosinophils, macrophages, lymphocytes, and, commonly, multinucleated giant cells. Here we report a case in a 6-year-old boy of differential diagnoses including dermatopathic lymphadenitis (DL), parasitic infection, Kimura’s disease, hypersensitivity reactions, cat-scratch disease, sinus histiocytosis with massive lymphadenopathy (SHML), hyperplasic lymph nodes, and lymphoma. Seema Lale, Daniel Soto, and Patricia G. Wasserman Copyright © 2014 Seema Lale et al. All rights reserved. Rhabdomyosarcoma with Pseudolipoblasts Arising in Ovarian Carcinosarcoma: A Distinctive Postchemotherapy Morphologic Variant Mimicking Pleomorphic Liposarcoma Wed, 22 Jan 2014 09:14:19 +0000 We describe a case of ovarian carcinosarcoma occurring in a 60-year-old female. The neoplasm was excised after neoadjuvant chemotherapy and contained a predominant heterologous pleomorphic rhabdomyosarcomatous component in which there were numerous multivacuolated rhabdomyoblasts that strongly mimicked lipoblasts. The clear cell variant of rhabdomyosarcoma is rarely documented, but this case shows a highly unusual finding in which the rhabdomyoblasts show the prominent multivacuolation with nuclear indentation characteristic of and indistinguishable from pleomorphic lipoblasts. This appears to represent a posttreatment phenomenon. As this finding might conceivably occur in other rhabdomyosarcomas after chemotherapy, we highlight the potential for diagnostic confusion with pleomorphic liposarcoma, which is usually diagnosed by morphology so that immunohistochemistry for muscle markers might not be performed. Khin Thway, Steve Hazell, Susana Banerjee, and Cyril Fisher Copyright © 2014 Khin Thway et al. All rights reserved. Primary Intraparenchymal Squamous Cell Carcinoma of the Kidney: A Rare and Unique Entity Mon, 20 Jan 2014 07:13:53 +0000 Primary squamous cell carcinoma (SCC) of the renal parenchyma is a very unusual entity which needs to be differentiated from primary SCC of renal pelvis, SCC from another primary site, and urothelial carcinoma with extensive squamous differentiation. We are most probably describing the second case of primary SCC of the renal parenchyma in a 51-year-old male who presented with heaviness of right upper abdomen with intermittent pain in right flank. Contrast-enhanced computed tomography (CECT) revealed a mass in the right lower pole of the kidney and histopathology following nephrectomy displayed the features of well-differentiated squamous cell carcinoma without urothelial involvement. Prithwijit Ghosh and Kaushik Saha Copyright © 2014 Prithwijit Ghosh and Kaushik Saha. All rights reserved. Concurrent Liver Hodgkin Lymphoma and Nodular Regenerative Hyperplasia on an Explanted Liver with Clinical Diagnosis of Alcoholic Cirrhosis at University Hospital Fundación Santa Fe de Bogotá Sun, 05 Jan 2014 06:44:31 +0000 Liver involvement by Hodgkin lymphoma (HL) is well documented. However, secondary liver failure to this neoplastic process is rare and usually presents late in the course of the disease. We present a case of a HL associated with nodular regenerative hyperplasia (NRH) diagnosed on an explanted liver from a 53-year-old patient with clinical diagnosis of alcoholic cirrhosis. Hematoxylin and eosin stain (H&E) showed abnormal liver architecture with hepatocytes nodules highlighted by reticulin stain with absent fibrosis on the trichrome stain. The portal spaces had diffuse infiltration by Reed-Sternberg cells positive for CD15, CD30, and latent membrane protein (LMP) on immunohistochemical studies. The patient also had a concurrent hilar lymph node biopsy that also showed HL involvement. Liver failure as the initial presentation of Hodgkin’ lymphoma is rare. We believe that more research about the utility of performing liver biopsies in patients candidates for transplantation with noncirrhotic hepatic failure is needed in order to establish the etiology and the optimal treatment. R. López, L. Barrera, A. Vera, and R. Andrade Copyright © 2014 R. López et al. All rights reserved. Myofibroblastoma of the Female Breast with Admixed but Distinct Foci of Spindle Cell Lipoma: A Case Report Sun, 29 Dec 2013 13:50:39 +0000 Mammary myofibroblastoma (MFB) is a rare benign spindle neoplasm that affects both sexes with a male predominance. It can exhibit a wide range of histological patterns. We report a case of epithelioid/spindle MFB of the female breast with admixed, but distinct, foci of spindle cell lipoma. Whilst all the spindle cells within the tumour expressed CD34, AR, ER, BCL2, and CD10, only those within the myofibroblastoma expressed desmin and only those within the lipomatous areas expressed S100. This finding, to our knowledge, is a novel one that has not been reported before. Hazem A. H. Ibrahim and Sami Shousha Copyright © 2013 Hazem A. H. Ibrahim and Sami Shousha. All rights reserved. Myolipoma of Mesentery: A Case Report Thu, 26 Dec 2013 15:03:54 +0000 Myolipomas are very rare benign lipomatous soft tissue tumors which are usually located in retroperitoneum, abdominal and pelvic cavity, and the abdominal wall. They can be diagnosed histologically by the presence of irregularly admixed mature adipose tissue and smooth muscle fibers. The correct diagnosis of myolipoma is important, because it should be considered in the differential diagnosis of fat-containing lesions of the soft tissue and should follow a benign clinical course despite its frequently large size and deep location. We report here a case of myolipoma arising in the mesentery of the jejunum. Hyun Sung Kim, Suk Kim, Kyungbin Kim, Kyung Un Choi, and Joo Youn Kim Copyright © 2013 Hyun Sung Kim et al. All rights reserved. Clear Cell Adenocarcinoma of the Renal Pelvis in a Male Patient Mon, 23 Dec 2013 14:17:55 +0000 Carcinoma of the renal pelvis is an uncommon renal neoplasm. Clear cell adenocarcinoma in the urinary tract is rare and has a histomorphology resembling that of the female genital tract. We herein present a case of clear cell adenocarcinoma of the renal pelvis, which is the first example in a male patient to our knowledge. A 54-year-old man presented with right flank pain. The tumor was associated with renal stones and hydronephrosis and invaded into the peripelvic fat tissue with regional lymph node metastasis. The patient died of metastatic disease six months postoperatively. Histologically, the tumor showed complex papillary architecture lined with clear and hobnail cells. Clear cell adenocarcinoma of the renal pelvis may pose a diagnostic challenge on histological grounds, particularly in the distinction from renal cell carcinoma. The immunohistochemical stains could help confirm the diagnosis. Due to its rarity, an effective treatment regimen remains to be determined. Sarawut Kongkarnka, Pruit Kitirattakarn, Hironori Katayama, and Surapan Khunamornpong Copyright © 2013 Sarawut Kongkarnka et al. All rights reserved. Follicular Lymphoma In Situ Presenting as Dermatopathic Lymphadenopathy Sun, 22 Dec 2013 18:50:52 +0000 Introduction. Follicular lymphoma in situ (FLIS) is a recently described entity with few cases recognized worldwide. To our knowledge, this is the first FLIS reported from West Africa. Case Presentation. We present the case of a 48-year-old civil servant with axillary lymphadenopathy discovered on routine mammography. On histology, a predominant reactive change with aggregates of melanophages was seen prompting a diagnosis of reactive lymphadenopathy. Immunohistochemistry done in our laboratory showed CD10 and Bcl-6 positive germinal centres with a small population of Bcl-2 positive germinal centre centre cells that were limited to some of the germinal centres. Conclusion. This highlights the use of immunohistochemistry in lymph node pathology—a resource which is very limited in our environment. Orah Nnamdi Obumneme, Igbokwe Uche, Banjo Adekunbiola, Akinde Ralph, and Irurhe Nicholas Copyright © 2013 Orah Nnamdi Obumneme et al. All rights reserved. Primary Subcutaneous Hydatid Cyst with Palisading Granulomatous Reaction Tue, 10 Dec 2013 13:58:53 +0000 Palisading granulomatous reactions are prominent microscopic characteristics that are seen in many diseases. Isolated subcutaneous cystic echinococcosis is rarely documented. Palisading granuloma as a host immune reaction to Echinococcus granulosus in an isolated primary subcutaneous hydatid cyst has been reported only once before. In this report, we are describing a 53-year-old male who developed a slowly growing subcutaneous thigh mass. Light microscopy confirmed the presence of hydatid cyst. Further radiological workup for liver and lung has not shown any visceral hydatid focus. Noorah Almadani, Bader Almutairi, and Ali H. Alassiri Copyright © 2013 Noorah Almadani et al. All rights reserved. Growth Patterns of Placental and Paraovarian Adrenocortical Heterotopias Are Different Sat, 07 Dec 2013 11:02:00 +0000 Two cases of adrenocortical heterotopia are reported. One is in a full-term placenta. The other is adjacent to the ovarian hilum of an adult. Both are incidental findings. Despite sharing similar histological and immunological features, they show different growth patterns. The literature is reviewed and adrenocortical heterotopias of different locations are compared. New hypotheses of its histogenesis are discussed. Hua Zhong, Bo Xu, and Dorota A. Popiolek Copyright © 2013 Hua Zhong et al. All rights reserved. Mucoepidermoid Carcinoma of the Intrapancreatic Common Bile Duct: Immunohistochemical Profile, Prognosis, and Review of the Literature Tue, 03 Dec 2013 11:55:44 +0000 Mucoepidermoid carcinoma of the bile duct is a rare entity. Only one mucoepidermoid carcinoma from the common bile duct has been reported in the Korean literature. Herein, we present the first in the English literature. The tumor arose in the intrapancreatic (distal) common bile duct in an 83-year-old woman who presented with obstructive jaundice and elevated liver enzymes. The tumor invaded the underlying pancreas and peripancreatic adipose tissue and showed pagetoid spread into the extrapancreatic common bile duct and cystic duct. The tumor exhibited nests of malignant cells with diffuse CK7 and MUC1 positivity. The basal cells were p63 and CK5/6 positive. The luminal cells were stained with carcinoembryonic antigen, MUC5, and mucicarmine and were focally positive for CK20. There was focal MUC4 staining on the apical luminal border. The neoplastic cells were negative for MUC2 and HER2-neu. We discuss the clinical presentation, diagnostic features, immunohistochemical profile, and prognosis of mucoepidermoid carcinoma of the common bile duct. The features of this neoplasm are further compared with mucoepidermoid carcinoma of the hepatobiliary system, adenosquamous carcinoma, and mucoepidermoid carcinoma of other organs. Adrienne E. Moul, Pablo A. Bejarano, Javier Casillas, Joe U. Levi, and Monica T. Garcia-Buitrago Copyright © 2013 Adrienne E. Moul et al. All rights reserved. Acinic Cell Carcinoma of the Breast Arising in Microglandular Adenosis Thu, 28 Nov 2013 18:23:42 +0000 Acinic cell carcinoma is a rare breast tumour belonging to salivary gland-like tumours of the breast. They are “triple-negative” breast cancers even if their biological behaviour seems to be more favourable. Herein we present an acinic cell carcinoma arising on a background of typical and atypical microglandular adenosis in a 58-year-old woman, along with a review of the literature. Jessica Falleti, Gino Coletti, Ettore Rispoli, Francesca Scarabeo, Mariarosaria Cervasio, Luigi Tornillo, Guido Pettinato, and Luigi Insabato Copyright © 2013 Jessica Falleti et al. All rights reserved. Calcifying Epithelial Odontogenic Tumor Wed, 27 Nov 2013 15:07:54 +0000 The calcifying epithelial odontogenic tumor (CEOT) is a rare benign epithelial odontogenic neoplasm of slow growth that is locally aggressive and tends to invade bone and adjacent soft tissue. Here is reported the case of a 21-year-old female patient with a CEOT in the left mandibular posterior region. The computerized tomography in coronal plane revealed a hypodense lesion in the posterior region of the left mandibular body with hyperdense areas inside and was associated with element 37. An incisional biopsy of the lesion was performed and the histopathological analysis revealed the presence of layers of epithelial odontogenic cells that formed prominent intercellular bridges. A large quantity of extracellular, eosinophilic, and amyloid-like material and an occasional formation of concentric calcifications (Liesegang rings) were also found. The histopathological diagnosis was a Pindborg tumor. Resection of the tumor with a safety margin was performed and after 6 months of follow-up there has been no sign of recurrence of the lesion. Olavo Hoston Gonçalves Pereira, Laura Priscila Barboza de Carvalho, Vilson Lacerda Brasileiro Junior, and Cláudia Roberta Leite Vieira de Figueiredo Copyright © 2013 Olavo Hoston Gonçalves Pereira et al. All rights reserved. Dermoid Cyst of the Pancreas: A Report of an Unusual Case and a Review of the Literature Thu, 14 Nov 2013 17:05:03 +0000 Pancreatic dermoid cysts are a rare entity. Preoperative diagnosis is difficult. The diagnosis is generally taking intraoperative. A 20-year-old female presented with epigastric pain without nausea, vomiting, diarrhea, fever, jaundice, and weight loss of one-month duration. Ultrasonography and computed tomography showed a smooth borders, solid, hyperechoic tumor within midline abdomen, without any connection to the stomach or spleen. At surgery, the entire mass was excised off of the head and inferior part of pancreas. Histopathologic evaluation revealed the rare diagnosis of a dermoid cyst. The diagnosis is difficult preoperatively in evaluating cystic pancreatic lesions by imaging. Therefore, we want to summarize the literature on this rare entity knowledge. Aynur Albayrak, Umran Yildirim, and Metin Aydin Copyright © 2013 Aynur Albayrak et al. All rights reserved. A Rare Component of Psammomatous Meningioma in a Testicular Teratoma Sun, 10 Nov 2013 09:38:54 +0000 We report a case of a psammomatous variant of meningioma arising in a pure and mature testicular teratoma. At immunohistochemistry, the meningiomatous component showed epithelial membrane antigen, S100 protein, and vimentin positive. Benign neoplasms arising in testicular teratomas are extremely rare. To our knowledge, we have not found any such report of psammomatous variant of meningioma in a testicular teratoma and any meningioma arising in a pure and mature testicular teratoma. This is a unique phenomenon. Fábio Meira Castro Pereira, Marbele Guimarães de Oliveira, Laiana do Carmo Almeida, Bruno Cunha Pires, and José de Bessa Júnior Copyright © 2013 Fábio Meira Castro Pereira et al. All rights reserved.