Digestive Diseases and Sciences, Vol. 50, No. 11 (November 2005), pp. 2170–2177 ( C  2005) DOI: 10.1007/s10620-005-3027-5 CASE REPORT Mucinous Cystic Tumor of the Pancreas with Ovarian-like Mesenchymal Stroma in a Male Patient BRIAN K. P. GOH, MBBS, MRCS, MMed(Surgery),* YU-MENG TAN, BSc(Hons), MBBS, FRCS,† M. PRIYANTHI KUMARASINGHE, MBBS, FRCPath,‡ and LONDON L. P. J. OOI, MBBS, FRCS, MD§ KEY WORDS: mucinous cystic tumor; male; ovarian-like stroma; ovarian-type stroma; estrogen receptor; progesterone receptor; mucinous cystic neoplasm; pancreas; cyst. Cystic neoplasms of the pancreas are rare primary neo- plasms of the pancreas. These tumors were first classified and divided into serous cystic neoplasms and mucinous cystic neoplasms by Compagno and Oertel in 1978 (1, 2). Mucin-producing tumors are generally regarded as ma- lignant or premaligant, whereas the serous counterparts are almost universally benign. Mucin-producing tumors were formally defined and classified as two separate en- tities, i.e., mucinous cystic tumor (MCT) and intraductal papillary mucinous tumor (IPMT), by the World Health Organization (WHO) in 1996 (3) and the Armed Forces Institute of Pathology (AFIP) in 1997 (4). Despite formal definitions of MCT and IPMT by WHO and AFIP, several controversies remain with regard to these two entities. Two of these issues which remain unre- solved are whether MCT can occur in males and whether the presence of ovarian-like stroma is essential in the diag- nosis of MCT. According to the WHO and AFIP definition, MCT must always have ovarian-type stroma and occurs almost exclusively in females (3, 4). Despite these defi- nitions, several large series of MCTs have reported that 16.7% to 42.6% of MCT patients are male (5–7) and thus the occurrence of MCTs in males does not seem exceed- ingly rare. However, careful examination of these studies revealed that the strict diagnostic criteria of MCT; espe- Manuscript received December 1, 2004; accepted February 8, 2005. From the *Department of Surgery, Singapore General Hospital, †Department of Surgery, Singapore General Hospital, Department of Surgical Oncology, National Cancer Centre Singapore, ‡Department of Pathology, Singapore General Hospital, and §Department of Surgery, Singapore General Hospital, Department of Surgical Oncology, National Cancer Centre Singapore. Address for reprint requests: Brian K. P. Goh, MBBS, MRCS, MMed(Surgery), Department of Surgery, Singapore General Hospital; bsgkp@hotmail.com. cially the presence of ovarian-like stroma as proposed by WHO and AFIP, were not always met. Recently, we reviewed 18 cases of MCTs resected at our institution over a 14-year period and found that all but one of the patients were females (8). The sole male patient had an MCT of the body of the pancreas which, on pathologi- cal examination, demonstrated ovarian-like stroma. To the best of our knowledge, only one previous case of muci- nous cystadenoma with ovarian-like stroma occurring in a male has been reported in the English literature (9). CASE REPORT A 28-year-old Chinese male presented with left iliac fossa pain of 2 weeks duration associated with weight loss. Plain ab- dominal radiograph demonstrated a region of calcification lo- cated to the left of the L1-2 disc space in the location of the pancreas. Computed tomography (CT ) of his abdomen was per- formed, which demonstrated a 4-cm cystic mass in the body and tail of the pancreas and calcification consistent with a mucinous cystadenoma (Figure 1). All the laboratory investigations in- cluding the liver function tests, carbohydrate antigen 19-9, and carcinoembryonic antigen were within normal limits. The pa- tient underwent exploratory laparotomy whereby a 3-cm pan- creatic cystic neoplasm was found in the tail of the pancreas. Spleen-preserving distal pancreatectomy was performed and the patient’s postoperative recovery was delayed by gastroparesis but was otherwise uneventful. Final histology confirmed a pan- creatic cystic neoplasm with features consistent with a muci- nous cystadenoma. The patient was followed up with annual CT scans and there was no evidence of recurrence up to 4 years postresection. Pathology. Grossly, there was a 3-cm unilocular cyst in the tail of the pancreas not communicating with the native pancre- atic ducts. The cyst was lined by columnar epithelium with basal nuclei and abundant pale mucous cytoplasm (Figure 2). The cyst wall demonstrated areas of hyaline collagenous thicken- ing, focal calcification, and subepithelial foci resembling ovarian 2170 Digestive Diseases and Sciences, Vol. 50, No. 11 (November 2005) 0163-2116/05/1100-2170/0 C  2005 Springer Science+Business Media, Inc.