10-YEAR TUMOR-FREE SURVIVAL AFTER INTRAOPERATIVE RADIATION THERAPY AND SECONDARY LIVER TRANSPLANTATION FOR HILAR CHOLANGIOCARCINOMA

Can the Limits of Liver Transplantation Be Expanded in Perihilar Cholangiocarcinoma?

The most common location of cholangiocarcinomas is the perihilar region with a frequency of 50-70%. Current standard treatment for perihilar cholangiocarcinomas (pCCA) is surgical resection. In cases where resection treatment is possible, the 5-year survival rate is 8-40%. However, using a very strict patient selection, neoadjuvant radiochemotherapy (NRCT), staging laparotomy, and liver transplantation (LT), called "the Mayo protocol," 5-year survivals of up to 70% in pCCA were reported. This treatment protocol clearly requires an intensive workforce and a harmonious multidisciplinary approach. Reoperation and retransplantation rates are high, which is a reflection of the NRCT. Multicenter studies, systemic reviews, and meta-analysis results, comparing both resection and LT in pCCA treatment and evaluating only LT results, pointed to LT with strict patient selection and full compliance with the treatment. The results of centers experienced in LT are better in treating pCCA. According to Mayo clinical data, histopathological diagnosis could not be obtained in half of the patients with pCCA before NRCT was given. This situation can be explained by the necrosis of the tumor due to the effect of NRCT and the fact that the tumor cannot be detected in the explant liver. This situation raises the following questions: did all patients actually have pCCA? Were these good results due to some patients not having pCCA? The 5-year survival rate was worse in patients with a pathological diagnosis than those without a pathological diagnosis. However, interestingly, recurrence rates were statistically similar in both groups. There was no difference in survival between LT and resection in the R₀N₀ subgroup in de novo pCCA. There are still many issues that need to be addressed and corrected in pCCA, which is one of the most problematic indications for LT. Significant success has been achieved with NRCT, staging laparotomy, and LT in selected patients with pCCA developing on the basis of PSC or early-stage unresectable de novo pCCA. It can be expected that new NRCT modalities will provide better survival by expanding the indications for LT in pCCA.

Vascular and nerval damage after intraoperative radiation therapy of the liver hilum in a large animal model

It has been demonstrated that intraoperative radiotherapy is a therapeutic option for patients suffering from perihilar cholangiocarcinoma. Aim of our study was to investigate vascular and nerve damages after irradiation of the liver hilum in a pig model. Twenty-four pigs underwent central bile duct resection followed by biliodigestive anastomosis. Nine pigs underwent this surgical procedure alone (group 1). Ten pigs were treated with additional intraoperative radiation therapy (IORT) of 20Gy to the liver hilum (group 2). And five pigs received operation and IORT with 40Gy to the area of anastomosis (group 3). Six weeks after operation and treatment the animals were sacrificed and histopathological examination was performed. Histology showed no vascular or nerve damage in non-irradiated perihilar tissue. Significant changes of nerve structures occurred, as well as vascular damage in large and even more in small hilar arteries in the irradiated neighboring liver tissue. In detail for small hilar arteries: intima proliferation (p ≤ .0001), endothelial swelling (p ≤ .0001), fibrinoid arterial wall necrosis (p ≤ .0001), and arterial thrombosis (p = .0079) were detected. Venous vessels did not show significant dose dependant cell damage. Overall, 20Gy as a single dose application during operation showed similar damage to vessels and nerves compared to 40Gy. A radiation dosage of 20Gy seems to be sufficient to induce necrosis due to vascular and nerve damage in potential malignant liver tissue with acceptable damage to surrounding tissue. Perineural invaded tumor cells might be diminished due to IORT.

[Liver transplantation for hilar cholangiocarcinoma]

Local non-resectable, hilar cholangiocarcinoma can be cured by performing a liver transplantation. The initially poor results after transplantation have significantly improved since neoadjuvant therapy protocols have been established. Therefore, hilar cholangiocarcinoma is now an accepted indication for liver transplantation in selected patients. This article summarizes the current state, recommendations and results of liver transplantation for these patients.

Liver transplantation for hilar cholangiocarcinoma: a German survey

BACKGROUND

The present study reports a German survey addressing outcomes in nonselected historical series of liver transplantation (OLT) for hilar cholangiocarcinoma (HL).

PATIENTS AND METHODS

We sent to all 25 German transplant centers performing OLT a survey that addressed (1) the number of OLTs for HL and the period during which they were performed; (2) the incidence of HL diagnosed prior to OLT/rate of incidental HL (for example, in primary sclerosing cholangitis); (3) tumor stages according to Union Internationale Centre le Cancer; (4) patient survival; and (5) tumor recurrence rate.

RESULTS

Eighty percent of centers responded, reporting 47 patients who were transplanted for HL. Tumors were classified as pT2 (25%), pT3 (73%), or pT4 (2%). HL was diagnosed incidentally in 10% of cases. A primary diagnosis of PSC was observed in 16% of patients. Overall median survival was 35.5 months. When in-hospital mortality (n = 12) was excluded, the median survival was 45.4 months, corresponding to 3- and 5-year survival rates of 42% and 31%, versus 31% and 22% when in-hospital mortality was included. HL recurred in 34% of cases. Three- and 5-year survivals for the 15 patients transplanted since 1998 was 57% and 48%, respectively. Median survival ranged from 20 to 42 months based on the time period (P = .014).

CONCLUSIONS

The acceptable overall survival, the improved results after careful patient selection since 1998, and the encouraging outcomes from recent studies all suggest that OLT may be a potential treatment for selected cases of HL. Prospective multicenter randomized studies with strict selection criteria and multimodal treatments seem necessary.

The role of liver transplantation in the treatment of hilar cholangiocarcinoma

Surgical resection or liver transplantation (LTx) are the only available treatments that offer a potential for long-term survival or cure in cases of hilar cholangiocarcinoma. Hilar resection in combination with partial hepatectomy and caudate lobectomy is regarded as the current treatment of choice. Overall 5-year survival rates range from 9% to 28%, and reach as high as 24-43% in R0 resections. Five-year survival rates in the very limited experience with LTx in hilar cholangiocarcinoma are not dramatically worse than those after resection. However, hilar cholangiocarcinoma is not at present an accepted indication for LTx given both the good results of LTx for benign diseases and the dramatic organ shortage. When compared with the prognosis of other gastrointestinal tumours, these survival rates are encouraging in the setting of an otherwise unresectable malignancy. As such, and considering the fact that it may represent the only possibility for cure, the general exclusion of patients with cholangiocarcinomas as candidates for LTx does not seem to be justified. Furthermore, recent advances in multimodal tumour therapy seem to be most promising in combination with LTx. Prospective studies are required to elucidate the influence of better patient selection and the role of multimodal treatments on the outcome of LTx in hilar cholangiocarcinoma. If the encouraging data achieved with neoadjuvant therapy prior to LTx are confirmed by further studies, we foresee that renewed interest in LTx for hilar cholangiocarcinoma could arise.