[Microcystic serous pancreatic cystadenoma]. / Cystadénome séreux microkystique du pancréas.

BACKGROUND: The pancreatic cystic serous neoplasms are divided into two categories: benign serous cystadenoma (SCA) and malignant serous cystadenocarcinoma. Furthermore, based on the macroscopic appearances, SCAs are subdivided into serous microcystic adenomas (SMAs) and serous oligocystic or macrocystic adenomas. AIM: Report of a new case of SMA in which we emphasize on the diagnostic difficulties encountered against such tumor despite its relatively radiological easiness compared to the other variants. CASE REPORT: We report the case of 84 year-old-woman with a microcystic serous cystadenoma of the pancreas which was identified on pathologic examination of the surgical specimen, after unconclusive abdominal ultrasound and computed tomography (CT)- scan. CONCLUSION: This case describes this rare entity and emphasizes that the diagnosis of such entity is still based on pathological examination after tumor removal.

An aggressive course of de novo ulcerative colitis after renal transplantation: colonic adenocarcinoma with choriocarcinomatous differentiation.

AIM: A rare case of colonic carcinoma arising in de novo ulcerative colitis after renal transplantation in a 42-year-old woman is reported. CASE: Clinically, the patient presented ulcerative colitis 8 years after renal transplantation, developed colonic cancer with liver metastasis 2 years later and died one month post operatively. Histologically, the removed tumor was composed of two distinctive elements consisting of adenocarcinoma and choriocarcinoma. The metastatic foci in the liver were composed exclusively of choriocarcinoma. Identification as choriocarcinoma was made on the basis of typical histological appearance, immunohistochemical demonstration of human chorionic gonadotropin (hCG) in the tumor cells and the high serum hCG level, unrelated to trophoblastic disease. In this report, pathogenesis is briefly discussed and clinical conditions are reviewed. CONCLUSION: In conclusion, the issue of de novo UC after organ transplantation is still a matter of debate. Further investigations are necessary to understand the tumorogenesis of colorectal cancer in de novo UC after renal transplantation,

[Parotid basal cell adenoma of membranous type]. / Adenome a cellules basales de type membraneux de la parotide.

INTRODUCTION: Basal cell adenoma (BCA) is a rare benign neoplasm characterized by the basaloid appearance of the tumour cells and the lack of myxo-chondroid stromal component present in pleomorphic adenoma. AIM: We report a case of basal cell adenoma of membranous type, highly suspected of malignancy because of the presence of mediastinal lymph nodes and pulmonary nodules which finally were related to an associated sarcoidosis. OBSERVATION: Our patient was an 80-year-old woman who presented a swelling of the right parotid two years ago. The clinical examination revealed a solid, indolent and mobile mass. A chest radiography noted mediastinal lymph nodes. The CT-scan confirmed the presence of mediastinal and tracheal lymph nodes with pulmonary nodules. So the diagnosis of metastatic malignant salivary gland tumor was suspected. Finally, the histological examination concluded to a basal cell adenoma of membranous type with sarcoidosis granulomas in the parotid and in the lymph nodes. CONCLUSION: The BCA is a benign tumor located generally in the parotid gland. When the malignancy is suspected, like in our case, this tumor must be differentiated from the basal cell adenocarcinoma using histological criteria.

[Multilocular cystic renal cell carcinoma]. / Le carcinome a cellules renales multiloculaire kystique.

BACKGROUND: Multilocular cystic renal cell carcinoma is an uncommon variant recently described of renal cell carcinoma. AIM: Analyze clinicopathological features, imaging findings and prognosis and therapeutic options of this tumor. CASE REPORTS: The authors reported two cases of multilocular cystic renal cell carcinoma arising in 68 and 39-year-old men. They were admitted with pain in the lumbar region and/or haematuria. The imaging findings were a renal neoplasm with cystic and solid areas. The pathologic findings confirm the diagnosis of multilocular cystic renal cell carcinoma. CONCLUSION: Multilocular cystic renal cell carcinoma, usually identified at earlier stages, had slower growth rate and was therefore associated with a better prognosis and longer survival than conventional renal cell carcinoma.

[The value of intraoperative frozen section in surgical management of thyroid nodules. Report of 409 cases]. / La valeur de l'examen extemporané dans la chirurgie des nodules thyroïdiens. A propos de 409 cas.

OBJECTIVE: The purpose of this study was to assess the value of intraoperative frozen section diagnosis in thyroid surgery and determine its limitations. METHODS: This retrospective study examined the results of 409 frozen sections of thyroid specimens analyzed over the 4-year period and their correlations with the final histological examination. RESULTS: In our series, frozen section diagnosis was concordant with subsequent histopathological examination in 96.6% of cases, discordant in 3.4%. All discordances were due to false-negative diagnoses. Non-false-positive result was found. The global specificity of frozen section analysis for all histological subtypes was 100% and its sensitivity was 68.2%. CONCLUSION: The frozen section evaluation of thyroid neoplasm is highly accurate and specific. A high degree of specificity with an acceptable sensitivity is requested. However, the frozen section examination has still some limits in the diagnosis of microfollicular lesions.

[Accuracy of frozen section diagnosis: an analysis of 1695 consecutive cases]. / Fiabilite de l'examen extemporane: analyse de 1695 examens consecutifs.

BACKGROUND: The intraoperative frozen section is a well established procedure for rapid diagnosis that helps in making therapeutic decisions. AIM: Assessment of the accuracy of frozen section diagnosis and analysis of the causes of its discordance. METHODS: A retrospective review of 1695 surgical specimens performed in 1207 patients between January 2002 and April 2005. Frozen section results were compared with the final diagnoses in paraffin sections. RESULTS: The frozen section diagnosis was benign in 84.2%, malignant in 10.2% and borderline in 0.4% of all cases. The frozen section result was deffered to permanent section in 5.2%. The sensitivity, specificity, positive and negative predictive values were 84.6%, 99.8%, 98.2% and 97.8% respectively. Overall diagnostic agreement was 97.5% (Kappa=0.88). Frozen section diagnosis was incorrect in 2.5% of cases. Most of the discrepancies were false negative cases frequently due to sampling errors and misinterpretation. False positive cases were always related with misinterpretation. CONCLUSION: The frozen section evaluation is highly accurate and reliable. However, the surgeon and the pathologist must be aware of its limitations.

46 XY pure gonadal dysgenesis with gonadoblastoma and dysgerminoma.

BACKGROUND: Swyer syndrome is a distinct type of pure gonadal dysgenesis characterized by a 46 XY karyotype in female phenotypic patients. It shows an abnormality in testicular differentiation. It is usually revealed by primary amenorrhea. The tumor that usually develops in Swyer syndrome is gonadoblastoma. Although gonadoblastoma is considered benign, the risk of malignant germ cell tumor development is high. OBJECTIVE: The aim of this report is to stress on the risk of occurrence of malignant germ cell tumors on these dysgenesic gonads. CASE REPORT: We present the clinical, sonographic and endocrine findings in the case of a 13 year-old phenotypic young girl with a 46 XY karyotype and gonadal dysgenesis. The patient underwent surgery for adnexal torsion. An examination of the gonads revealed gonadoblastoma associated to dysgerminoma. The treatment and the follow up are detailed. CONCLUSION: The presence of Y chromosome in the karyotype of a patient presenting a gonadal dysgenesis must lead to prophylactic bilateral gonadectomy in order to avoid a malignant transformation. Gonadectomy must be followed by a hormone replacement therapy.

Sinonasal leiomyoma: an exceptional localization.

BACKGROUND: Most of the sinonasal tumours are of epithelial origin. Leiomyomas are very uncommon in the upper respiratory tract and extremely rare in the nasal cavity and paranasal sinuses. They account for less than 2.5% of the mesenchymal neoplasms of the sinonasal tract and the nasopharynx. AIM: Report of a new case which will be added to the 30 cases of primary sinonasal leiomyogenic tumours reported in the litterature. The clinical and pathological characteristics of this tumour will be discussed. CASE REPORT: We report a case of 48-year-old woman complaining of nasal obstruction corresponding to a polypoid lesion of the sinonasal cavity. The histological examination of the removed mass concluded to a leiomyoma. CONCLUSION: Leiomyoma in this location has no specific physical or radiological findings. Only the histological examination can definitively made the correct diagnosis.

[Diagnostic value of immunohistochemistry in ovarian sex cord-stromal tumors]. / Apport de l'immunohistochimie dans le diagnostic des tumeurs stromales de l'ovaire.

BACKGROUND: The ovarian tumors' diagnosis is based on biological and radiologic tests but only the histological examination associated to an immunohistochemical study allow best diagnosis. AIM: The purposes of this study is to examine inhibin and other markers immunoreactivity to ovarian sex cord-stromal tumors and their histological mimics and to discuss its value in the differential diagnosis. METHODS: We report a retrospective study of 31 cases of ovarian sex cord-stromal tumors and review the clinical, pathologic and immunohistochimical features of these tumors. RESULTS: The average age of our patients was 51,3 years with an average size of 8,4cm. Immunostaining for inhibin was positive in 66% of granulosa cell tumor, in 50% of Sertoli-Leydig cell tumor and in 54% of thecoma-fibroma group. Inhibin immunoreactivity was more important than with cytokeratin and epithelial membrane antigen, but less marked than with CD99, vimentin, smooth muscle actin, desmin and S-100 protein. CONCLUSION: The results of this study show that although it is not complete specificity, inhibin, contrarily to the other markers, can be used to help in the distinction between ovarian sex cord-stromal neoplasms and the other primary and metastatic tumors.

[Abdominal desmoid tumor: pathologic and therapeutic concepts]. / Tumeur desmoide abdominale: concepts histopathologiques et therapeutiques.

BACKGROUND: Abdominal desmoid tumors arise in young adults between 20 and 40 years. They are characterized by a local recurrence in 20 to 30% of cases. AIM: review the clinical and pathologic features of this entity, look for the expression of immunohistochemical markers (actine, desmine, CD34, vimentin) and also to estimate the expression of two potential targets therapy; the hormonal receptors and the CD117. METHODS: From 1990 to 2004, three cases of abdominal desmoid tumors were diagnosed in the Pathologic laboratory of the Charles Nicole Hospital of Tunis. RESULTS: The study concerned three women 62, 35 and 30 year-old. All the patients were operated and the size of tumours varied to 5 to 7cm. The CD117 and the hormonal receptors were negative in every case. None of the patients presented local recurrence. CONCLUSION: Abdominal desmoid tumors are locally aggressive but never give metastasis. The negativity of these lesions to the CD117 and in the hormonal receptors does not imply resistance in the hormonal treatment by anti-estrogens.

[Solid pseudopapillary tumors of the pancreas: a pediatric case report]. / Tumeur solide pseudopapllaire du pancreas: a propos d'une observation pediatrique.

BACKGROUND: Solid pseudopapillary tumors of the pancreas are extremely rare and mostly seen in young females. It is often diagnosed incidentally or during investigations of gastrointestinal complaints. AIM: Report of a pediatric case of this tumor. CASE REPORT: We report the case of a 15-year old teenager who presented with painful abdominal tumefaction. Imaging findings were a 12 cm solid and cystic mass originating from the tail of the pancreas. A distal pancreatectomy with splenectomy was performed. Pathologic examination concluded to solid pseudopapillary tumor. Evolution was favorable with no recurrence 18 months after surgery. CONCLUSION: Histological examination confirms the diagnosis and allows, with the help of immunohistochemical study, to rule out some differential diagnoses such as pancreatoblastoma, acinar tumors and endocrine tumors. Prognosis of solid pseudopapillary tumors of the pancreas is excellent after radical resection and recurrences are rarely seen.

[Contribution of immunohistochemical detection of human herpesvirus-8 latent nuclear antigen-1 in the diagnosis of Kaposi disease]. / Apport de la détection immunohistochimique de l'antigène nucléaire de latence 1 de l'herpes virus humain 8 dans le diagnostic de la maladie de Kaposi.

AIMS: To study the immunohistochemical expression of HHV8 in Kaposi's lesions and in other vascular lesions and to determine the utility of this technique in differentiating between Kaposi's disease (KD) and other vascular lesions. METHODS: Fixed, paraffin-embedded tissue sections from 25 cases of KD, 9 cases of hemangioma, 2 cases of angiolymphoid hyperplasia with eosinophilia and 9 cases of angiosarcoma were examined immunohistochemically using the monoclonal antibody monoclonal LNA 53 (ABI). Strong, nuclear and granular staining in at least a cell was considered as a positive result. RESULTS: Sixteen cases of KD showed positive staining, whereas all cases of hemangioma, angiolymphoid hyperplasia with eosinophilia and angiosarcoma were negative for this antigen CONCLUSION: Immunohistochemical detection of the human herpesvirus-8 latent nuclear antigen-1 is a useful for differentiating between KD and other vascular lesions.

[Histopathological study of gastric polyps. A report of 65 cases]. / Etude anatomo-pathologique des polypes gastriques. A propos de 65 cas.

In a retrospective study of the specimens of gastric polypectomy, carried out between January 1992 and December 2002, we analysed the demographic and histological aspects of 65 polyps. This study revealed hyperplastic polyps in 66%, adenomatous lesions in 9.2%, Peutz-Jeghers polyps in 7.7%, inflammatory fibroid polyps in 6.15%, two cases of focal foveolar hyperplasia (3%), two cases of Brunner's gland heterotopia (3%), 1 pancreatic heterotopia (1.5%), 1 fundic gland polyp (1.5%) and 1 carcinoid tumor (1.5%). All adenomas and two Peutz-Jeghers polyps include intraepithelial neoplasia. Moreover, we identified a case of Brunner's gland heterotopia, which contain a focus of plane tubular adenoma with high-grade intraepithelial neoplasia. Other lesions were found within the polyps or into the surrounding gastric mucosa, such as intestinal metaplasia and Helicobacter Pylori gastritis. This work allowed us to recommend complete removal of gastric polyps and the realization of biopsies of the nonpolypoid gastric mucosa in the search of intraepithelial neoplasia or other lesions with malignant potential.