Mucin-producing Bile Duct Tumor of the Caudate Lobe Protruding into the Common Hepatic Duct

Mucin-producing tumor in the bile duct is referred to clinically as mucin-producing bile duct tumor (MPBT). Intraductal papillary neoplasm of the biliary tract that resembles an intraductal papillary mucinous neoplasm (IPMN) of the pancreas is a rare category of MPBT and is not well characterized. We, herein, report a case of MPBT of the caudate lobe of the liver that showed papillary growth and communicated with the bile duct of the caudate lobe and protruded into the common hepatic duct. Histologically, MPBT cells showed papillary overgrowth with abundant mucinous secretions, resembling an IPMN of the pancreas. The MPBT cells showed the same immunostaining pattern as that of cells from IPMN of the pancreas.     

Podoplanin expression in the cyst wall correlates with the progression of intraductal papillary mucinous neoplasm

A thickened, enhanced cyst wall on imaging examinations is one of the “worrisome features” described in the consensus guidelines for management of intraductal papillary mucinous neoplasm of the pancreas (IPMN). Podoplanin (PDPN) expression by cancer-associated fibroblasts is known to be an indicator of poor prognosis in some types of cancer. We performed immunohistochemical staining for alpha-smooth muscle actin (α-SMA) in IPMN lesions and determined the pathological wall thickness by measuring the thinnest and thickest α-SMA-positive parts of the wall of the largest cyst in each case, and the mean of these two values was recorded as the wall thickness. The thickness of the pathological wall increased with progression from IPMN with low-grade dysplasia to IPMN with an invasive carcinoma. The pathological wall was thicker in IPMN with main duct involvement, nongastric-type IPMN, and IPMN with mural nodules. We also stained for PDPN and assessed the thickness of cyst wall staining as for α-SMA. The thickness of the PDPN-positive cyst wall varied in a pattern similar to the thickness of the α-SMA-positive pathological cyst wall. PDPN-positive stromal fibroblasts in the invasive component of IPMN-IC were evaluated as a ratio to α-SMA-positive fibroblasts. A high ratio (>50 %) of PDPN-positive stromal fibroblasts was a predictor of poor outcome. PDPN expression in the cyst wall correlates with the progression of IPMN. PDPN may be a significant prognostic marker of IPMN-IC.     

The risk of lymph node metastasis in mucosal gastric carcinoma: especially for a mixture of differentiated and undifferentiated adenocarcinoma

Background/Aims: Endoscopic submucosal dissection (ESD) is gaining wider acceptance for the treatment of early gastric carcinoma (EGC) and its indication has been extended to mucosal gastric carcinoma with undifferentiated component in some institutes. Our aims were to confirm the frequency of lymph node metastasis in such cases and clarify the demarcation in indications for ESD. Methodology: We evaluated medical data of 287 patients with mucosal gastric carcinoma who underwent surgical resection between 1996 and 2008. The tumours were histologically classified into purely differentiated (PD), differentiatedpredominant mixed (DPM), undifferentiated-predominant mixed (UPM) and purely undifferentiated (PU) types. Results: Lymph node metastasis was identified in seven (2.4%) of the 287 patients and was detected more frequently in UPM (10%, two of 20) and PU (4%, four of 98), compared with PD (none of 148) (p=0.01 and 0.02, respectively). In mixed-type carcinoma, size was a significant risk factor for lymph node metastasis (p=0.04). Conclusions: It might be better to select gastrectomy rather than ESD for the treatment of mucosal gastric carcinoma with an undifferentiated component.     

Feasibility of laparoscopic gastrectomy for advanced gastric cancer with positive peritoneal cytology

Purpose

The role of gastrectomy for patients with positive peritoneal cytology, but a negative macroscopic peritoneal implant (P?/cy+), remains unclear. The aim of this study was to evaluate laparoscopic gastrectomy for P?/cy+ patients.

Methods

This study reviewed a prospectively maintained gastric cancer database of gastric-cancer patients those underwent surgical resection. P?/cy+ gastric cancer that had invaded the subserosa, or deeper layers, of the stomach wall without distant organ metastases was considered operable in this institution. P?/cy+ patients underwent either open or laparoscopic gastrectomy with D2 lymphadenectomy. The short-term results were examined to assess differences in outcome between the two groups.

Results

Eighteen P?/cy+ patients without distant organ metastases underwent surgery between 2000 and 2010. Laparoscopic gastrectomy was performed in nine patients and open gastrectomy in nine patients. The estimated blood loss was significantly smaller, the resumption of food intake earlier, and the length of postoperative hospital stay shorter in the patients that underwent laparoscopic gastrectomy than in the patients that underwent open gastrectomy. There were no significant differences in the 2-year survival rates between the groups.

Conclusion

Laparoscopic gastrectomy for P?/cy+ patients is a minimally invasive and safe oncologic procedure with good short-term results.