Clinicopathological and prognostic significance of DNA mismatch-repair protein expression in gastric adenocarcinoma

Although the significance of DNA mismatch repair (MMR) protein expression in colorectal cancer is well-established, it remains contentious in extra-colorectal cancers and mainly in gastric adenocarcinoma. Data from Africa and Arab world remain limited. This study explored the MMR expression in gastric adenocarcinoma and evaluated its clinicopathological and prognostic signification among Tunisian patients. A retrospective study of 72 gastric adenocarcinomas was carried out. Clinicopathological particularities and patient outcomes were recorded. MMR expression was determined by immunohistochemistry on whole sections of archived material. Survival analysis was realized utilizing the Kaplan-Meier estimates and Log-Rank test. Expression of MMR proteins was observed in 84.7% of gastric adenocarcinoma samples. The 11 remaining samples (15.3%) exhibited an altered pattern of MMR protein. A significant association was identified between deficient MMR expression and advanced age (p = 0.03), intestinal type (p = 0.04) and lymph node metastases (p = 0.04). No other significant relationship was observed with the remaining selected tumor features. Patient survival was significantly associated with lymph node invasion (p = 0.002), distant metastases (p = 0.02) and tumor differentiation (p = 0.03), but not with MMR status (p = 0.83). MMR deficiency was related to advanced-age, intestinal type and nodal metastasis, but not to survival of Tunisian patients with gastric adenocarcinoma. Larger multicenter studies with additional molecular investigation are required to more explore these tumors.

Bien que l'importance de l'expression des protéines de réparation des mésappariements de l'ADN (MMR) dans le cancer colorectal soit bien établie, elle reste controversée dans les cancers extra-colorectaux et principalement dans l'adénocarcinome gastrique. Les données de l'Afrique et du monde arabe restent limitées. Cette étude a exploré l'expression des protéines MMR dans l'adénocarcinome gastrique et a évalué sa signification clinicopathologique et pronostique chez les patients tunisiens. Une étude rétrospective de 72 adénocarcinomes gastriques a été réalisée. Les particularités clinicopathologiques et pronostiques des patients ont été enregistrées. L'expression des protéines MMR a été déterminée par immunohistochimie. L'analyse de survie a été réalisée en utilisant la méthode de Kaplan-Meier et le test Log-Rank. L'expression des protéines MMR a été observée dans 84,7 % des échantillons d'adénocarcinome gastrique. Les 11 cas restants (15,3 %) présentaient un profil d'expression altérée des protéines MMR. Une association significative a été identifiée entre l'expression déficiente de MMR et l'âge avancé (p = 0,03), le type intestinal (p = 0,04) et les métastases ganglionnaires (p = 0,04). Aucune autre relation significative n'a été observée avec les autres caractéristiques tumorales sélectionnées. La survie des patients était significativement associée à l'envahissement des ganglions lymphatiques (Log Rank, p = 0,002), aux métastases à distance (Log Rank, p = 0,02) et à la différenciation tumorale (Log Rank, p = 0,03), mais pas à l'expression de MMR (Log Rank, p = 0,03). Rang, p = 0,83). Le déficit de l'expression des protéines MMR était lié à l'âge avancé, au type intestinal et aux métastases ganglionnaires, mais pas à la survie des patients tunisiens ayant un adénocarcinome gastrique. Des études multicentriques avec des investigations moléculaires supplémentaires sont nécessaires pour explorer davantage le cancer gastrique avec expression déficiente des protéines MMR.

The input of GATA-3 in the identification of parathyroid carcinoma diagnosis: Case report with review of literature.

INTRODUCTION: and Importance: Parathyroid carcinoma is an exceptional cancer, with significant morbidity and mortality, associated with parathyroid hormone (PTH) mediated hypercalcemia. CASE PRESENTATION: We report a case of parathyroid carcinoma with a difficult histological diagnosis. This case illustrates the usefulness of the immunohistochemical marker "GATA-3" in parathyroid differentiation especially in tumours. CLINICAL DISCUSSION: The diagnosis of parathyroid carcinoma is challenging without the knowledge of the clinical information, laboratory finding, and radiographic imaging studies. The immunohistochemistry is useful tool in these cases to identify the parathyroid origin of neoplasia. GATA-3 is a transcription factor that is involved in the embryonic development of the parathyroid glands and in adult parathyroid cell proliferation. CONCLUSION: It is concluded that GATA-3 is a very sensitive and relatively specific immunohistochemical marker for parathyroid differentiation that can assist in the differential diagnosis of parathyroid tumours.

[Adenomatoid odontogenic tumor: about two cases]. / La tumeur adénomatoïde odontogène: à propos de deux observations.

Adenomatoid odontogenic tumor is a benign epithelial tumor which mainly affects young women. It usually occurs in the anterior portion of the upper jaw. Diagnosis can be clinically suspected in patients with cyst formation associated with retained tooth but histopathological confirmation is required. This study involved two patients aged 13 and 37 years, with no previous history, presenting after the occurrence of a swelling on the jaw and mandible. Anatomopathological examination of these lesions showed adenomatoid odontogenic tumor. This study highlights the anatomoclinical features, outcome and treatment of this type of tumor.

Histopathological diagnosis of strongyloidiasis hyperinfection in Tunisian patient with hodgkin lymphoma: Case report.

INTRODUCTION: Strongyloides stercoralis, an intestinal nematode, is commonly dispersed throughout the tropical and subtropical regions. Strongyloides stercoralis infection typically contributes to an asymptomatic chronic disease which can remain hidden for decades. However, in immunocompromised patients, the hyperinfection can take place, causing high mortality rates. CASE PRESENTATION: A 45 year-old Tunisian women, with heavy medical history, suffering of stage 3 classic Hodgkin lymphoma under treatment; presented with complaints of epigastric pain, nausea, vomiting. Gastroduodenoscopy showed duodenal and gastric erythematous and ulcerated mucosa. Histological assessment showed chronic infiltration with a large amount of eosinophils around numerous helminth forms identified as larvae of Strongyloides stercoralis. CONCLUSION: Early detection of Strongyloides stercoralis infection in immunocompromised patients is life saving and avoids fatality caused by hyperinfection or systemic dissemination. Routine stool examination may be negative, so histopathological identification of the parasite in tissue sections provides the definite diagnosis.

The importance of using fine-needle aspiration cytology in the diagnosis of thyroid nodules.

BACKGROUND: Thyroid nodules are common diseases, frequent in middle-aged women; only 5%-30% are malignant. Fine needle aspiration cytology is a simple, rapid and non invasive diagnostic test, performed to predict malignancy and avoid unnecessary surgery.The aim of this study is to evaluate the accuracy of fine needle aspiration in the management of thyroid lesions. MATERIALS AND METHODS: Our study was retrospective, including all cases of thyroid fine needle aspiration between January 2010 and December 2017, which were verified by microscopic examination, Data was obtained from the files of Pathology and ENT Department of Farhat Hached Hospital of Sousse and from nuclear medicine department of Sahloul Hospital of Sousse, Tunisia. RESULTS: A total of 58 cases were studied, the main age was 40 ± 15,57 years and the sex ratio was 0.03 with female predominance. Concordance between fine needle aspiration and histology was seen in 45 cases. The sensitivity was 60% and the specificity was 100%. The negative and positive predictive values were 100 and 92%, respectively. The concordance index Kappa was of 0.67. CONCLUSION: Thyroid fine needle aspiration in experienced hands is an easily performed diagnostic procedure with very little associated risk. It should be performed in suspect nodules for treatment stratification.

Primary adenoid cystic carcinoma of the lung: A case report and literature review.

Primary adenoid cystic carcinoma (ACC) of the lung is an unusual thoracic neoplasm with slow growing and low-grade malignancy. Usually, it is diagnosed at a higher clinical stage and is difficult to resect due to its central location. Herein, we report a 56-year-old man with hemoptysis associated with dyspnea and weight loss lasting for one month. Bronchial fibroscopy highlighted a budding nodular tumor in the left main bronchus. The patient underwent a left pneumonectomy with mediastinal lymphadenomectomy. Microscopic examination showed tumor cells infiltrating the bronchial wall and the cartilage and concluded to an ACC of the left bronchus. Ear, nose, and throat examination as well as cervico-facial magnetic resonance imaging were performed to search a primary salivary gland tumor and were returned without abnormalities. The tumor was classified as a primary ACC of the left bronchus without lymph node metastasis. To avoid their misdiagnosis, ACCs of the lung should be well known by the pathologist and surgeons. Their pathological features may be misleading and referring to a benign lesion, however, the presence of cribriform foci and infiltrative pattern are very suggestive. Although, indolent and slow growing tumor, long-term recurrences are quite frequent, especially in case of unclear surgical margin.

Inhabitual presentation of Sertoli-Leydig cell tumor of the ovary with xeroderma pigmentosum: Case report with review of literature.

INTRODUCTION: Sertoli-Leydig cell tumors (SLCTs) are rare sex-cord stromal tumors of the ovary. Heterologous components may be present, most commonly in the intermediate differentiated and poorly differentiated groups. Because of their scarcity, SLCTs with heterologous differentiation represent a challenge in both diagnosis and management, with limited available experience. PRESENTATION OF CASE: We report a case of a 27-year-old, Tunisian woman, followed in the Dermatology Department since the age of six months for xeroderma pigmentosum, with a history of basal cell carcinoma of the face operated on several times. The patient presented with abdominal pain and bloating associated with a medium abundance ascites on physical exam. Ultrasound showed a large left adnexal mass associated with an elevated cancer antigen 125 on serological exam. The patient underwent unilateral salpingo-oophorectomy with resection of two omental nodules. Microscopic examination concluded to poorly differentiated Sertoli-Leydig tumor with rhabdomyomatous differentiation. Adjuvant chemotherapy was performed and there was no clinical evidence of tumor recurrence during the three years of follow-up. DISCUSSION: SLCTs with rhabdomyomatous differentiation on the setting of xeroderma pigmentosum are exceptional, microscopic diagnosis and management is challenging, considering the tumor scarcity. CONCLUSION: Further case reports and retrospective studies are required to more understand the pathogenesis of SLCTs and to determine their optimal treatment regimen.

Significance of p53, p27, Ki-67, E-cadherin, and HER2 expression in upper urinary tract urothelial carcinoma.

BACKGROUND: The study investigated the expression and the clinicopathological significance of p53, p27, Ki-67, E-cadherin, and HER2 in upper urinary tract urothelial carcinomas (UTUC) from Tunisian patients. We performed a retrospective study of 66 UTUC. Main clinicopathological features were reported. The expression of p53, p27, Ki-67, E-cadherin, and HER2 was investigated by immunohistochemistry on whole tissue section. RESULTS: Expression of p53, Ki-67, p27, E-cadherin, and HERE2 was reported in 36.4%, 69.7%, 90.9%, 100%, and 0% of cases, respectively. p53 expression was associated with stage (p = 0.001), positive surgical margin (p = 0.005), and shorter recurrence-free survival (RFS; Log Rank test, p = 0.026). Ki-67 and p27 expression was associated with stage (p < 0.001 and p = 0.001, respectively) and grade (p < 0.001 and p = 0.001, respectively). Using Kaplan-Meier test, the positive surgical margin was associated with shorter RFS compared to free surgical margin (Log Rank test, p = 0.031). Moreover, in univariate Cox regression analysis, surgical margin (p = 0.041; HR 0.325, 95% CI 0.110-0.956) and p53 expression (p = 0.035; HR 0.328, 95% CI 0.116-0.925) were the significant factors associated with RFS. CONCLUSIONS: Together, our findings suggest that positive surgical margin and p53 expression were potential prognostic factors of UTUC since both were associated with shorter RFS in Tunisian patients.

Investigation of simian virus 40 (SV40) and human JC, BK, MC, KI, and WU polyomaviruses in glioma.

The gliomagenesis remains not fully established and their etiological factors still remain obscure. Polyomaviruses were detected and involved in several human tumors. Their potential implication in gliomas has been not yet surveyed in Africa and Arab World. Herein, we investigated the prevalence of six polyomaviruses (SV40, JCPyV, BKPyV, MCPyV, KIPyV, and WUPyV) in 112 gliomas from Tunisian patients. The DNA sequences of polyomaviruses were examined by PCR assays. Viral infection was confirmed by DNA in situ hybridization (ISH) and/or immunohistochemistry (IHC). The relationships between polyomavirus infection and tumor features were evaluated. Specific SV40 Tag, viral regulatory, and VP1 regions were identified in 12 GBM (10.7%). DNA ISH targeting the whole SV40 genome and SV40 Tag IHC confirmed the PCR findings. Five gliomas yielded JCPyV positivity by PCR and DNA ISH (2.7%). However, no BKPyV, KIPyV, and WUPyV DNA sequences were identified in all samples. MCPyV DNA was identified in 30 gliomas (26.8%). For GBM samples, MCPyV was significantly related to patient age (p = 0.037), tumor recurrence (p = 0.024), and SV40 (p = 0.045) infection. No further significant association was identified with the remaining tumor features (p > 0.05) and patient survival (Log Rank, p > 0.05). Our study indicates the presence of SV40, JCPyV, and MCPyV DNA in Tunisian gliomas. Further investigations are required to more elucidate the potential involvement of polyomaviruses in these destructive malignancies.

Targeted next generation sequencing screening of Lynch syndrome in Tunisian population.

A high colorectal cancer (CRC) incidence is observed in Tunisia, with a relatively high proportion of patients developing CRC before the age of 40. While this suggests a genetic susceptibility, only a few Tunisian Lynch Syndrome families have been described. In this study we aimed to identify the underlying genetic cause in 32 patients with early onset CRC and/or a positive family history. Of twenty-four patients' tumor or biopsies could be analyzed with immunohistochemical staining to detect loss of expression of one of the MMR proteins. Ten tumors showed loss of expression, of which one tumor was from a patient where a germline pathogenic MSH2 variant was detected previously with Sanger sequencing. Next generation sequencing of the MMR, POLE and POLD1 genes was performed in leukocyte and tumor DNA of the remaining nine patients, as well as in two patients with MMR-proficient tumors, but with severe family history. In six of 11 patients a germline variant was detected in MLH1 (n = 5) or MSH2 (n = 1). Two of six patients were from the same family and both were found to carry a novel in-frame MLH1 deletion, predicted to affect MLH1 function. All MLH1 variant carriers had loss of heterozygosity with retention of the variant in the tumors, while a somatic pathogenic variant was detected in the patient with the germline MSH2 variant.

Laryngeal synovial sarcoma: Report of 2 cases.

Synovial sarcoma is a malignant mesenchymal tumor. It most commonly occurs in the lower extremities of young adults. The head and neck are rare sites, accounting for less than 10%. The larynx is an extremely rare site. We report two cases of 27 and 18 year-old men who developed a synovial sarcoma of the larynx. They presented with hoarseness of voice and hemoptysis. Endoscopy detected a mass in the supraglottic region. The biopsy concluded a synovial sarcoma. Immunohistochemistry conveyed diagnostic certainty. They had been treated with total laryngectomy and post-operative radiotherapy. The 2 patients are seen for regular follow-ups in our department and they remained recurrence-free for 10 years and 24 months, respectively. Synovial sarcoma is a very rare tumor of the larynx. A multidisciplinary therapeutic approach is essential for the management of this malignancy. Long-term follow-up is required to monitor for recurrence and improve disease-free survival.

Very rare localization of a retroperitoneal hemangiopericytoma revealed by lumbosciatalgia: A case report.

INTRODUCTION: Hemangiopericytoma is a rare vascular tumor representing about 1% of all vascular tumors and approximatively 5% of all soft tissues sarcomas that arises from the pericytes of Zimmerman surrounding capillaries and postcapillaries vessels. Retroperitoneal hemangiopericytomas are rare among the localisations as it usually occurs in lower and upper extremities. PRESENTATION OF CASE: We present a case of 31-year-old man with a well-defined retro peritoneal mass measuring about 105 × 73 × 83 mm at right lower quadrant of the abdomen anterior to right psoas muscle. Intraoperatively, an large mass measuring 10 × 8 cm was found arising from the retro peritoneum. A monobloc excision was performed. The postoperative course was uneventful. Histopathological examination with immune histochemistry revealed that tumoral cells were positive for desmin, CD34, smooth muscular antigen. Final diagnosis of hemangiopericytoma was made. On the last follow up at one year, he was symptom free. DISCUSSION: Hemangiopericytoma is a rare tumor. It takes origin from pericytes presenting as intervals along the walls of capillaries and post-capillary venules. Retroperitoneal hemangiopericytoma is a rare location. It is often discovered at late course, and can be revealed by various symptoms with the compression of the adjacent organs by the tumor Surgical resection should be considered in symptomatic cases or in case of diagnostic dilemma. CONCLUSION: Retroperitoneal hemangiopericytoma can be benign but it should be treated the same way as aggressive tumors. It requires a careful and long term follow up.

Immunohistochemical Characterization Improves the Reproducibility of the Histological Diagnosis of Ovarian Carcinoma

Background: Ovarian cancer is the leading cause of gynecologic cancer-related death. Histological assessment remains the standard clue for the diagnosis of ovarian carcinoma. Misinterpretation and inconsistent application of histological criteria may lead to significant interobserver variability and poor reproducibility of the diagnosis. In this study, we investigated the discrepancy in histological diagnosis and the significance of a designed panel of immunohistochemical markers for the improvement of the diagnostic reproducibility of ovarian carcinomas. Methods: We performed a retrospective study on 74 ovarian carcinomas. All tumor slides were independently reviewed by two pathologists. The results for seven available immunomarkers as p53, WT-1, p16INK4A, CK7, CK20, and estrogen and progesterone receptors were determined for all cases by immunohistochemistry. Results: The histological diagnosis review performed using standard histology showed a concordance of diagnoses in 86% of cases with Cohen's kappa of 0.80. Immunohistochemical results increased significantly the diagnosis reproducibility with a concordance of 91% and a Cohen's kappa of 0.86 (P = 0.001). Conclusion: Although the histological diagnosis remains reliable, the use of a designed panel of immunohistochemical markers improves significantly the interobserver concordance and the classification accuracy of ovarian carcinomas.

HPV infection and p16INK4A and TP53 expression in rare cancers of the uterine cervix.

Cervix cancer remains among most commonly diagnosed cancer in developing countries. Except squamous cell carcinoma and adenocarcinoma, the etiopathology and oncogenic mechanisms of rare cancers remain largely unknown. The study was performed to investigate the value of HPV infection and the expression of p16INK4A and TP53 in rare primitive cancers of the cervix. We conducted a retrospective study of rare primitive cancers of the cervix. Main clinicopathological features were reported. HPV infection was detected by in situ hybridization. Expression of p16INK4A and TP53 was analyzed by immunohistochemistry. Overall, seven cases were identified, including basaloid squamous cell carcinoma (BSCC, n = 2), small cell neuroendocrine carcinoma (SCNEC), granulocytic sarcoma without acute myeloid leukemia, leiomyosarcoma, primitive neuroectodermal tumor and botryoid-type embryonic rhabdomyosarcoma. The mean age of patients was 53.7 years. Four cancers were diagnosed at advanced stages. The prognosis was unfavorable and associated with patient death in five cases. HPV types 16/18 were detected in BSCCs and SCNEC. Strong and diffuse p16INK4A overexpression was described in the nucleus and the cytoplasm of all tumor cells of BSCCs and SCNEC. The remaining cancers exhibited only scattered and focal p16INK4A staining. Mutated TP53 protein was detected in BSCC (case 1) and GS. Rare cancers of the cervix are aggressive and associated with poor prognosis. In contrast to mesenchymal tumors, BSCCs and SCNEC are etiologically related to high-risk HPV infection and could be identified by block positive p16INK4A overexpression as common cancers of the cervix. TP53 mutations are not a negligible genetic event in rare cervical cancers.

Ossifying fibromyxoid tumor of the trunk mimicking hydatid cyst: A case report.

INTRODUCTION: Ossifying fibromyxoid tumor (OFMT) is a rare lesion that generally occurs in the soft tissues of proximal limbs, head or neck and presents as a slowly growing mass. Abdominal or trunk locations are extremely rare. PRESENTATION OF CASE: We report a case of 50-year-old man who presented with a painless, slow growing epigastric mass for 5 years. Radiologic assessment revealed a well circumscribed median subcutaneous parietal mass lesion present in front of the xiphoid process suspicious of a calcified hydatid cyst. Diagnosis of OFMT was made on histopathological examination of the resected specimen. DISCUSSION: OFMT most often presents as a single swelling arising from the subcutaneous soft tissues or skeletal muscles of the extremities. Multifocal presentation is exceedingly rare. Radiologically, a peripheral shell of bone is seen in more than 50% cases. On MRI, myxofibrous stroma appears isointense to muscle on T1 and of intermediate to high signal intensity on T2. Surgical excision is the mainstay of treatment. Histologically, the tumor has a thick fibrous capsule with a complete or partial underlying layer of metaplastic woven or lamellar bone. Tumor is composed of uniform round, ovoid, or spindle-shaped cells arranged in nests and cords embedded in a variably myxoid and collagenous Alcian blue-positive stroma. On immunochemistry, the tumor cells are positive for S100 protein and desmin in 90% and 50% cases respectively. CONCLUSION: OFMT is a rare soft tissue tumor with malignant potential often misdiagnosed as a benign lesion. Complete surgical excision should be performed to prevent local recurrence.

Rare triad of periampullary carcinoid, duodenal gastrointestinal stromal tumor and plexiform neurofibroma at hepatic hilum in neurofibromatosis type 1: a case report.

BACKGROUND: Neurofibromatosis type 1 is a relatively common inherited disorder. Patients with neurofibromatosis type 1 are at high risk of developing neurogenic, neuroendocrine and mesenchymal intra-abdominal tumors. Although coexistence of multiple tumors of different types is frequent in neurofibromatosis type 1, simultaneous occurrence of abdominal tumors of three types in very rare. CASE PRESENTATION: A 66-year-old lady with neurofibromatosis type 1 presented with painless progressive jaundice for six months. Laboratory investigations revealed iron deficiency anemia and conjugated hyperbilirubinemia. Tumor markers were normal. Abdominal computed tomography showed a 3 × 2 cm heterogenous mass in the periampullary region with mild dilation of the common bile duct and another 2 × 1.7 cm mass in the fourth portion of the duodenum. Endoscopic biopsy confirmed the diagnosis of periampullary carcinoid. At surgery, multiple small nodules were detected at the hepatic hilum. Frozen section suggested them to be neurofibromas. Patient underwent pancreatoduodenectomy and had uneventful recovery with no recurrence at two months. Microscopic examination of the resected specimen confirmed presence of three tumors: periampullary well differentiated neuroendocrine tumor, gastrointestinal stromal tumor of the fourth part of duodenum and plexiform neurofibroma at the hepatic hilum. CONCLUSION: Patients of neurofibromatosis type 1 with abdominal symptoms should be treated with high index of clinical suspicion and thoroughly evaluated to rule out multiple tumors.

Large bronchogenic cyst of stomach: A case report.

INTRODUCTION: Bronchogenic cysts are congenital cysts arising as an abnormal budding from primitive tracheobronchial tree. They are lined by pseudostratified columnar or cuboidal ciliated epithelium and contain smooth muscle fibers, submucosal bronchial glands and/or cartilage. They are most frequently located in the mediastinum or the lung parenchyma. Intramural occurrence of bronchogenic cyst in the gastric wall is very rare. PRESENTATION OF CASE: We present a case of 65-year-old lady with a 7×8cm lesion in the gastric cardia suspicious of gastrointestinal stromal tumor. Because of the large size, total gastrectomy with Roux-en-Y esophagojejunal anastomosis was performed. The postoperative course was uneventful. Histopathological examination revealed a sub-mucosal cyst lined by PCCE with presence of smooth muscle fibers and focal mucous glands. Final diagnosis of bronchogenic cyst was made. On the last follow up at one year, she was symptom free. DISCUSSION: On extensive Medline/Pubmed search, only 38 cases of gastric bronchogenic cysts were found to be reported till date. They are typically located in the posterior gastric wall close to the gastric cardia. On radiological imaging, they appear as well defined intramural cystic lesion without any characteristic features. Surgical resection is considered in symptomatic cases or in case of diagnostic dilemma. CONCLUSION: Gastric bronchogenic cysts often mimic gastrointestinal stromal tumor on preoperative imaging. They should be included in the differential diagnosis while dealing with an intramural gastric lesion close to the cardia or gastroesophageal junction.

Retroperitoneal unicentric Castleman's disease: A case report.

INTRODUCTION: Castleman's disease (CD) is an angio-follicular lymph node hyperplasia presenting as a localized or a systemic disease masquerading malignancy. The most common sites of CD are mediastinum, neck, axilla and pelvis. Unicentric CD in the peripancreatic region is very rare. PRESENTATION OF CASE: We report a case of the 34-year-old lady presenting with epigastric pain for 3 months. Abdominal imaging revealed a retroperitoneal mass arising from the pancreas suspected to be neuroendocrine tumor. Tumor markers were not elevated. Complete surgical excision was performed and patient had uneventful recovery. Pathologic findings demonstrated localized hyaline-vascular type of Castleman's disease. DISCUSSION: CD is a very rare cause for development of retroperitoneal mass. It is more frequent in young adults without predilection of sex. It can occur anywhere along the lymphoid chain. Abdominal and retroperitoneal locations usually present with symptoms due to the mass effect on adjacent organs. CD appears as a homogeneously hypoechoic mass on ultrasound and non-specific enhancing homogeneous mass with micro calcifications on computed tomography. Histologically, the hyaline vascular type demonstrates a follicular and inter-follicular capillary proliferation with peri-vascular hyalinization, with expansion of the mantle zones by a mixed inflammatory infiltrate of numerous small lymphocytes and plasma cells. The standard therapy of localized form is en bloc surgical excision as performed in our case. CONCLUSION: Unicentric CD in the peripancreatic region is difficult to differentiate from pancreatic neoplasm preoperatively. However, preoperative biopsy in cases of high clinical suspicion can help in avoiding extensive surgery for this benign disease.

Distribution of molecular breast cancer subtypes among Tunisian women and correlation with histopathological parameters: a study of 194 patients.

According to the immunohistochemical test of estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor-2 (Her-2), breast cancer can be divided into 4 molecular subtypes: luminal A, luminal B, Her-2, and basal-like. The purpose of this study is to correlate these subtypes with clinicopathological features. We have selected from the files of our Pathology Department 194 breast carcinomas which had already been studied for ER, PR, and Her-2, diagnosed between January 2008 and October 2009. The cases were classified into 4 molecular subtypes. The clinicopathological characteristics of each subtype were compared. The luminal A subtype was the most prevalent (51.5%). The basal-like and Her-2 subtypes were significantly correlated to a large tumor size, a high tumor grade, and a high-volume nodal involvement (≥4). On multivariate analysis, patients with the Her-2 and basal-like subtypes were 4.2 (95% CI, 1.3-13.5) times more likely to have developed metastases in four or more lymph nodes than those with luminal tumors. Our analysis revealed that the Her-2 and basal-like subtypes are correlated with factors associated with a poor prognosis. The luminal A subtype is the commonest subtype, showing that breast cancer in Tunisia has no aggressive phenotype.