p53 expression in synovial sarcoma and its association with prognostic factors.

Background: Synovial sarcoma is an aggressive tumor and has two common histological subtype, biphasic and monophasic. It has SYT-SSX gene fusion that decreases expression of p53 tumor suppressor. The prognosis is associated with mitosis and tumor diameter. Therefore this study conducted to know the pattern of p53 expresion and its association with mitosis, histological subtype, and other prognosis factors. Methods: Twenty synovial sarcoma cases consisted of 4 monophasic and 16 biphasic cases from Cipto Mangunkusumo Hospital – Faculty of Medicine, Universitas Indonesia (CMHospital-FMUI) 2005-2011 were analyzed for association of p53 expression and mitosis as prognostic factor. Haematoxylin-eosin slides were used to count mitosis. Paraffin block materials were used to analyze p53 expression by immunohistochemistry and to detect SYT gene translocation by FISH (Fluorescein in situ Hybridization). Results: The Fisher’s exact test showed that positive p53 expression was associated with tumor diameter <5 cm although it was not associated with mitosis. The histological subtype has no association with p53 expression and mitosis. Unfortunately, only 7/19 cases were positive for FISH-SYT gene translocation. Conclusion: In synovial sarcoma, p53 expression is associated with tumor diameter.

Hepatoid carcinoma of the gallbladder.

Hepatoid carcinoma is a special type of extrahepatic tumor associated with hepatic differentiation, and has the morphological and functional features of hepatocellular carcinoma. Hepatoid carcinoma of the gallbladder is very rarely reported in the literature. We report a case of hepatoid carcinoma of the gallbladder in a 71-year-old female who presented with abdominal pain and was first diagnosed as cholelithiasis with cholecystitis. The microscopic findings of the gallbladder after cholecystectomy showed an area of tumor with polygonal cells, eosinophilic cytoplasm, distinct cell borders, round vesicular nuclei and prominent nucleoli, arranged in trabecular pattern resembling hepatocellular carcinoma intermingled with areas of adenocarcinoma or cholangiocarcinoma. The specimen from the pancreas also showed the same type of tumor cells. Histochemically, some of tumor cells were positive for Victoria Blue, Stein, and PAS. The immunohistochemistry for alpha-fetoprotein (AFP) showed strong intra cytoplasmic positivity, both in tumor cells with hepatic differentiation and tumor cells with bile duct epithelium differentiation. Based on these findings, this case was diagnosed as hepatoid carcinoma of the gallbladder with metastasis to the pancreas. This is the first case that has been reported in our department.