Biliodigestive anastomosis after intraoperative irradiation in swine.

A large animal model was established to investigate the feasibility and suitable dosage of intraoperative radiation therapy (IORT) to the hepatic hilum before biliary-enteric anastomosis is performed. Twenty-two Pietrain Hampshire pigs underwent gallbladder and proximal bile duct resection followed by IORT using 20-40 Gy and performing biliary-enteric anastomosis. In the follow-up period of 56 days, pigs developed dose-dependent complications like stenosis of the biliary-enteric anastomosis. Results demonstrate that IORT of the liver hilum up to 20 Gy is safe with acceptable early complications in the presented animal model. The porcine biliary-enteric anastomosis can tolerate intraoperative irradiation up to a dosage of 40 Gy without disruption.

Intraoperative radiation therapy in liver tissue in a pig model: monitoring with dual-modality PET/CT.

PURPOSE: To assess, in a pig model, the value of dual-modality positron emission tomography (PET)/computed tomography (CT) for monitoring radiation therapy. MATERIALS AND METHODS: Central bile duct resection followed by creation of a biliodigestive anastomosis was performed in nine pigs. Six of these pigs were also treated with intraoperative radiation therapy (IORT) (20 Gy) in the area of the anastomosis. Two, 4, and 8 weeks postoperatively, contrast material-enhanced fluorine 18 fluorodeoxyglucose (FDG) PET/CT of the liver was performed in all of the animals. The radioactive tracer concentration in the region of the anastomosis was quantified, and the values were compared intraindividually with the values at the liver periphery. Histologic evaluation of the liver was performed 8 weeks postoperatively. The PET/CT images were assessed for changes in liver volume and bile duct diameter over time. RESULTS: In all nine pigs, the region of the anastomosis could be clearly defined on the fused PET/CT images. PET/CT revealed a decreased concentration of FDG in the irradiated field 2 and 4 weeks after IORT. At 8 weeks, however, the distribution of the tracer in the irradiated pigs did not differ from that in the nonirradiated pigs. Homogeneous tracer uptake in all liver regions was observed in the nonirradiated animals. The CT images showed an increase in liver volume in all pigs and bile duct dilatation that increased over time in the irradiated pigs. CONCLUSION: The morphologic and functional changes due to IORT in liver tissue can be accurately monitored with dual-modality PET/CT. By enabling the integration of functional and morphologic data, PET/CT may have an important role in monitoring radiation treatment.

Combined external beam and intraluminal radiotherapy for irresectable Klatskin tumors.

BACKGROUND: In most cases of proximal cholangiocarcinoma, curative surgery is not possible. Radiotherapy can be used for palliative treatment. We report our experience with combined external beam and intraluminal radiotherapy of advanced Klatskin's tumors. PATIENTS AND METHODS: 30 patients were treated for extrahepatic proximal bile duct cancer. Our schedule consisted of external beam radiotherapy (median dose 30 Gy) and a high-dose-rate brachytherapy boost (median dose 40 Gy) delivered in four of five fractions, which could be applied completely in twelve of our patients. 15 patients in the brachytherapy and nine patients in the non-brachytherapy group received additional low-dose chemotherapy with 5-fluorouracil. RESULTS: The brachytherapy boost dose improved the effect of external beam radiotherapy by increasing survival from a median of 3.9 months in the non-brachytherapy group to 9.1 months in the brachytherapy group. The effect was obvious in patients receiving a brachytherapy dose above 30 Gy, and in those without jaundice at the beginning of radiotherapy (p < 0.05). CONCLUSIONS: The poor prognosis in patients with advanced Klatskin's tumors may be improved by combination therapy, with the role of brachytherapy and chemotherapy still to be defined. Our results suggest that patients without jaundice should be offered brachytherapy, and that a full dose of more than 30 Gy should be applied.

Role of radiation after operative palliation in cancer of the proximal bile ducts.

Cancer of the proximal bile ducts continues to pose a formidable problem to even the most experienced biliary surgeon. From 1977 through 1985, 51 patients with histologically confirmed proximal bile duct cancers underwent surgical treatment. The lesion was confined to the hilar region in 30 patients; there was extensive hepatic infiltration or distant metastatic disease in 21 patients. One patient underwent resection. Biopsy only was performed in six patients. In the remaining 44 patients, transtumoral dilation and intubation were performed. These 44 patients were further analyzed with regard to how survival was affected by the presence of metastatic disease and by the adjunctive use of radiation therapy. Mean survival in those patients with metastatic disease (n = 16) was 6.1 months, and survival was not improved by the use of postoperative radiation. In the absence of metastatic or advanced local disease, however, the addition of external beam radiation did significantly extend the mean survival from 4.5 to 12.2 months and the median survival from 2.2 to 12.2 months. The operative mortality for the series was 14% and postoperative complications occurred in 18 patients. These findings suggest that the addition of external beam radiation improves survival in patients undergoing palliative treatment of hilar tumors. Further confirmation of the value of radiation awaits prospective investigation.