The Effect of Histopathological Growth Patterns of Colorectal Liver Metastases on the Survival Benefit of Adjuvant Hepatic Arterial Infusion Pump Chemotherapy.

BACKGROUND: Histopathological growth patterns (HGPs) are a prognostic biomarker in colorectal liver metastases (CRLM). Desmoplastic HGP (dHGP) is associated with liver-only recurrence and superior overall survival (OS), while non-dHGP is associated with multi-organ recurrence and inferior OS. This study investigated the predictive value of HGPs for adjuvant hepatic arterial infusion pump (HAIP) chemotherapy in CRLM. METHODS: Patients undergoing resection of CRLM and perioperative systemic chemotherapy in two centers were included. Survival outcomes and the predictive value of HAIP versus no HAIP per HGP group were evaluated through Kaplan-Meier and Cox regression methods, respectively. RESULTS: We included 1233 patients. In the dHGP group (n = 291, 24%), HAIP chemotherapy was administered in 75 patients (26%). In the non-dHGP group (n = 942, 76%), HAIP chemotherapy was administered in 247 patients (26%). dHGP was associated with improved overall survival (OS, HR 0.49, 95% CI 0.32-0.73, p < 0.001). HAIP chemotherapy was associated with improved OS (HR 0.61, 95% CI 0.45-0.82, p < 0.001). No interaction could be demonstrated between HGP and HAIP on OS (HR 1.29, 95% CI 0.72-2.32, p = 0.40). CONCLUSIONS: There is no evidence that HGPs of CRLM modify the survival benefit of adjuvant HAIP chemotherapy in patients with resected CRLM.

Progressive plasticity during colorectal cancer metastasis.

Metastasis is the principal cause of cancer death, yet we lack an understanding of metastatic cell states, their relationship to primary tumor states, and the mechanisms by which they transition. In a cohort of biospecimen trios from same-patient normal colon, primary and metastatic colorectal cancer, we show that while primary tumors largely adopt LGR5 + intestinal stem-like states, metastases display progressive plasticity. Loss of intestinal cell states is accompanied by reprogramming into a highly conserved fetal progenitor state, followed by non-canonical differentiation into divergent squamous and neuroendocrine-like states, which is exacerbated by chemotherapy and associated with poor patient survival. Using matched patient-derived organoids, we demonstrate that metastatic cancer cells exhibit greater cell-autonomous multilineage differentiation potential in response to microenvironment cues than their intestinal lineage-restricted primary tumor counterparts. We identify PROX1 as a stabilizer of intestinal lineage in the fetal progenitor state, whose downregulation licenses non-canonical reprogramming.

Genetic And Morphological Evaluation (GAME) score for patients with colorectal liver metastases.

BACKGROUND: This study sought to develop a clinical risk score for resectable colorectal liver metastasis (CRLM) by combining clinicopathological and clinically available biological indicators, including KRAS. METHODS: A cohort of patients who underwent resection for CRLM at the Johns Hopkins Hospital (JHH) was analysed to identify independent predictors of overall survival (OS) that can be assessed before operation; these factors were combined into the Genetic And Morphological Evaluation (GAME) score. The score was compared with the current standard (Fong score) and validated in an external cohort of patients from the Memorial Sloan Kettering Cancer Center (MSKCC). RESULTS: Six preoperative predictors of worse OS were identified on multivariable Cox regression analysis in the JHH cohort (502 patients). The GAME score was calculated by allocating points to each patient according to the presence of these predictive factors: KRAS-mutated tumours (1 point); carcinoembryonic antigen level 20 ng/ml or more (1 point), primary tumour lymph node metastasis (1 point); Tumour Burden Score between 3 and 8 (1 point) or 9 and over (2 points); and extrahepatic disease (2 points). The high-risk group in the JHH cohort (GAME score at least 4 points) had a 5-year OS rate of 11 per cent, compared with 73·4 per cent for those in the low-risk group (score 0-1 point). Importantly, in cohorts from both the JHH and MSKCC (747 patients), the discriminatory capacity of the GAME score was superior to that of the Fong score, as demonstrated by the C-index and the Akaike information criterion. CONCLUSION: The GAME score is a preoperative prognostic tool that can be used to inform treatment selection.

Survival after resection of perihilar cholangiocarcinoma-development and external validation of a prognostic nomogram.

BACKGROUND: The objective of this study was to derive and validate a prognostic nomogram to predict disease-specific survival (DSS) after a curative intent resection of perihilar cholangiocarcinoma (PHC). PATIENTS AND METHODS: A nomogram was developed from 173 patients treated at Memorial Sloan Kettering Cancer Center (MSKCC), New York, USA. The nomogram was externally validated in 133 patients treated at the Academic Medical Center (AMC), Amsterdam, The Netherlands. Prognostic accuracy was assessed with concordance estimates and calibration, and compared with the American Joint Committee on Cancer (AJCC) staging system. The nomogram will be available as web-based calculator at mskcc.org/nomograms. RESULTS: For all 306 patients, the median overall survival (OS) was 40 months and the median DSS 41 months. Median follow-up for patients alive at last follow-up was 48 months. Lymph node involvement, resection margin status, and tumor differentiation were independent prognostic factors in the derivation cohort (MSKCC). A nomogram with these prognostic factors had a concordance index of 0.73 compared with 0.66 for the AJCC staging system. In the validation cohort (AMC), the concordance index was 0.72, compared with 0.60 for the AJCC staging system. Calibration was good in the derivation cohort; in the validation cohort patients had a better median DSS than predicted by the model. CONCLUSIONS: The proposed nomogram to predict DSS after curative intent resection of PHC had a better prognostic accuracy than the AJCC staging system. Calibration was suboptimal because DSS differed between the two institutions. The nomogram can inform patients and physicians, guide shared decision making for adjuvant therapy, and stratify patients in future randomized, controlled trials.

Long-term outcomes following microwave ablation for liver malignancies.

BACKGROUND: Microwave ablation has emerged as a promising treatment for liver malignancies, but there are scant long-term follow-up data. This study evaluated long-term outcomes, with a comparison of 915-MHz and 2.4-GHz ablation systems. METHODS: This was a retrospective review of patients with malignant liver tumours undergoing operative microwave ablation with or without liver resection between 2008 and 2013. Regional or systemic (neo)adjuvant therapy was given selectively. Local recurrence was analysed using competing-risk methods with clustering, and overall survival was determined from Kaplan-Meier curves. RESULTS: A total of 176 patients with 416 tumours were analysed. Colorectal liver metastases (CRLM) comprised 81.0 per cent of tumours, hepatocellular carcinoma 8.4 per cent, primary biliary cancer 1.7 per cent and non-CRLM 8.9 per cent. Median follow-up was 20.5 months. Local recurrence developed after treatment of 33 tumours (7.9 per cent) in 31 patients (17.6 per cent). Recurrence rates increased with tumour size, and were 1.0, 9.3 and 33 per cent for lesions smaller than 1 cm, 1-3 cm and larger than 3 cm respectively. On univariable analysis, the local recurrence rate was higher after ablation of larger tumours (hazard ratio (HR) 2.05 per cm; P < 0.001), in those with a perivascular (HR 3.71; P = 0.001) or subcapsular (HR 2.71; P = 0.008) location, or biliary or non-CRLM histology (HR 2.47; P = 0.036), and with use of the 2.4-GHz ablation system (HR 3.79; P = 0.001). Tumour size (P < 0.001) and perivascular position (P = 0.045) remained significant independent predictors on multivariable analysis. Regional chemotherapy was associated with decreased local recurrence (HR 0.49; P = 0.049). Overall survival at 4 years was 58.3 per cent for CRLM and 79.4 per cent for other pathology (P = 0.360). CONCLUSION: Microwave ablation of liver malignancies, either combined or not combined with liver resection, and selective regional and systemic therapy resulted in good long-term survival. Local recurrence rates were low after treatment of tumours smaller than 3 cm in diameter, and those remote from vessels.

Perioperative complications influence recurrence and survival after resection of hepatic colorectal metastases.

BACKGROUND: Perioperative outcomes, such as blood loss, transfusions, and morbidity, have been linked to cancer-specific survival, but this is largely unsupported by prospective data. METHODS: Patients from a previous, randomized trial that evaluated acute normovolemic hemodilution during major hepatectomy (≥3 segments) were reevaluated and those with metastatic colorectal cancer (n = 90) were selected for analysis. Survival data were obtained from the medical record. Disease extent was measured using a clinical-risk score (CRS). Log-rank test and Cox proportional hazard model were used to evaluate recurrence-free survival (RFS) and overall survival (OS). RESULTS: Median follow-up was 71 months. The CRS was ≥3 in 45 % of patients; 59 % had extrahepatic procedures. Morbidity and mortality were 33 and 2 %, respectively. Postoperative chemotherapy was given to 87 % of patients (78/90) starting at a median of 6 weeks. RFS and OS were 29 and 60 months, respectively. Postoperative morbidity significantly reduced RFS (23 vs. 69 months; P < 0.001) and OS (28 vs. 74 months; P < 0.001) on uni- and multi-variate analysis; positive resection margins and high CRS also were significant factors. Delayed initiation of postoperative chemotherapy (≥8 weeks) was common in patients with complications (37 vs. 12 %; P = 0.01). CONCLUSIONS: In this selected cohort of patients from a previous RCT, perioperative morbidity was strongly (and independently) associated with cancer-specific outcome. It also was associated with delayed initiation of postoperative chemotherapy, the impact of which on survival is unclear.

Hepatic arterial nodal metastases in pancreatic cancer: is this the node of importance?

BACKGROUND: The hepatic artery lymph node (HALN) is frequently sampled during pancreaticoduodenectomy (PD). Data suggest that survival in the setting of HALN metastases is similar to that of stage IV pancreatic ductal adenocarcinoma (PDAC). The objectives of this study were to describe the prognostic significance of HALN metastases and to assess the predictive performance of HALN compared to peripancreatic lymph node status. METHODS: Patients undergoing PD for PDAC from January 2000-October 2010 were identified from a prospectively maintained database. Patients were included if during PD the HALN was submitted for pathologic evaluation. Patients were excluded if margins were macroscopically positive, if pathology was found to be consistent with a diagnosis other than PDAC. Overall (OS) and disease-free survival (DFS) were estimated by Kaplan-Meier methods. RESULTS: Of the 671 patients who underwent PD for PDAC, HALN status was analyzed for 147 patients. HALN was positive in 23 patients (16 %), 38 were peripancreatic lymph node (PPLN) and HALN negative, and 86 were PPLN+/HALN-. Median follow-up for survivors was 10 months. In a multivariable model, lymph node status and tumor differentiation predicted OS and DFS. Hazard of death and relapse/death were highest among the HALN+ patients (hazard ratio [HR] 2.94; p = 0.017 and HR 2.66; p = 0.011, respectively). Kaplan-Meier analysis revealed significant differences in OS (p = 0.017) and DFS (p = 0.013) based on lymph node status. CONCLUSIONS: OS and DFS are significantly reduced in patients with a positive HALN. Differentiation and lymph node status were predictors of OS and DFS. In the multivariate models, differentiation and lymph node status remain independent predictors of OS and DFS.

Malignant progression in IPMN: a cohort analysis of patients initially selected for resection or observation.

BACKGROUND: Intraductal papillary mucinous neoplasms (IPMN) may represent a field defect of pancreatic ductal instability. The relative risk of carcinoma in regions remote from the radiographically identified cyst remains poorly defined. This study describes the natural history of IPMN in patients initially selected for resection or surveillance. METHODS: Patients with IPMN submitted to resection or radiographic surveillance were identified from a prospectively maintained database. Comparisons were made between these two groups. RESULTS: From 1995 to 2010, a total of 356 of 1,425 patients evaluated for pancreatic cysts fulfilled inclusion criteria. Median follow-up for the entire cohort was 36 months. Initial resection was selected for 186 patients (52 %); 114 had noninvasive lesions and 72 had invasive disease. A total of 170 patients underwent initial nonoperative management. Median follow-up for this surveillance group was 40 months. Ninety-seven patients (57 % of those under surveillance) ultimately underwent resection, with noninvasive disease in 79 patients and invasive disease in 18. Five of the 18 (28 %) invasive lesions developed in a region remote from the monitored lesion. Ninety invasive carcinomas were identified in the entire population (25 %), ten of which developed the invasive lesion separate from the index cyst, representing 11 % with invasive disease. CONCLUSIONS: Invasive disease was identified in 39 % of patients with IPMN selected for initial resection and 11 % of patients selected for initial surveillance. Ten patients developed carcinoma in a region separate from the radiographically identified IPMN, representing 2.8 % of the study population. Diagnostic, operative, and surveillance strategies for IPMN should consider risk not only to the index cyst but also to the entire gland.

Downstaging in pancreatic cancer: a matched analysis of patients resected following systemic treatment of initially locally unresectable disease.

BACKGROUND: Patients with locally unresectable pancreatic cancer (AJCC stage III) have a median survival of 10-14 months. The objective of this study was to evaluate outcome of initially unresectable patients who respond to multimodality therapy and undergo resection. METHODS: Using a prospectively collected database, patients were identified who were initially unresectable because of vascular invasion and had sufficient response to nonoperative treatment to undergo resection. Overall survival (OS) was compared with a matched group of patients who were initially resectable. Case matching was performed using a previously validated pancreatic cancer nomogram. RESULTS: A total of 36 patients with initial stage III disease were identified who underwent resection after treatment with either systemic therapy or chemoradiation. Initial unresectability was determined by operative exploration (n = 15, 42%) or by cross-sectional imaging (n = 21, 58%). Resection consisted of pancreaticoduodenectomy (n = 31, 86%), distal pancreatectomy (n = 4, 11%), and total pancreatectomy (n = 1, 3%). Pathology revealed T3 lesions in 26 patients (73%), node positivity in 6 patients (16%), and a negative margin in 30 patients (83%). The median OS in this series was 25 months from resection and 30 months since treatment initiation. There was no difference in OS from time of resection between the initial stage III patients and those who presented with resectable disease (P = .35). CONCLUSIONS: In this study, patients who were able to undergo resection following treatment of initial stage III pancreatic cancer experienced survival similar to those who were initially resectable. Resection is indicated in this highly select group of patients.

Prospective study of outcomes after percutaneous biliary drainage for malignant biliary obstruction.

BACKGROUND: Percutaneous biliary drainage (PBD) is used to relieve malignant bile duct obstruction (MBO) when endoscopic drainage is not feasible. Little is known about the effects of PBD on the quality of life (QoL) in patients with MBO. The aim of this study was to evaluate changes in QoL and pruritus after PBD and to explore the variables that impact these changes. MATERIALS AND METHODS: Eligible patients reported their QoL and pruritus before and after PBD using the Functional Assessment of Cancer Therapy-Hepatobiliary instrument (FACT-HS) and the Visual Analog Scale for Pruritus (VASP). Instruments were completed preprocedure and at 1 and 4 weeks following PBD. RESULTS: A total of 109 (60 male/49 female) patients enrolled; 102 (94%) had unresectable disease. PBD was technically successful (hepatic ducts cannulated at the conclusion of procedure) in all patients. There were 2 procedure-related deaths. All-cause mortality was 10% (N = 11) at 4 weeks and 28% (N = 31) at 8 weeks post-PBD with a median survival of 4.74 months. The mean FACT-HS scores declined significantly (P < .01) over time (101.3, 94.8, 94.7 at baseline, 1 week, 4 weeks, respectively). The VASP scores showed significant improvement at 1 week with continued improvement at 4 weeks (P < .01). CONCLUSIONS: PBD improves pruritus but not QoL in patients with MBO and advanced malignancy. There is high early mortality in this population.

Regional chemotherapy for unresectable primary liver cancer: results of a phase II clinical trial and assessment of DCE-MRI as a biomarker of survival.

BACKGROUND: This study reports the results of hepatic arterial infusion (HAI) with floxuridine (FUDR) and dexamethasone (dex) in patients with unresectable intrahepatic cholangiocarcinoma (ICC) or hepatocellular carcinoma (HCC) and investigates dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) assessment of tumor vascularity as a biomarker of outcome. PATIENTS AND METHODS: Thirty-four unresectable patients (26 ICC and eight HCC) were treated with HAI FUDR/dex. Radiologic dynamic and pharmacokinetic parameters related to tumor perfusion were analyzed and correlated with response and survival. RESULTS: Partial responses were seen in 16 patients (47.1%); time to progression and response duration were 7.4 and 11.9 months, respectively. Median follow-up and median survival were 35 and 29.5 months, respectively; 2-year survival was 67%. DCE-MRI data showed that patients with pretreatment integrated area under the concentration curve of gadolinium contrast over 180 s (AUC 180) >34.2 mM.s had a longer median survival than those with AUC 180 <34 mM.s (35.1 versus 19.1 months, P = 0.002). Decreased volume transfer exchange between the vascular space and extracellular extravascular space (-DeltaK(trans)) and the corresponding rate constant (-Deltak(ep)) on the first post-treatment scan both predicted survival. CONCLUSIONS: In patients with unresectable primary liver cancer, HAI therapy can be effective and safe. Pretreatment and early post-treatment changes in tumor perfusion characteristics may predict treatment outcome.

Phase I trial of adjuvant hepatic arterial infusion (HAI) with floxuridine (FUDR) and dexamethasone plus systemic oxaliplatin, 5-fluorouracil and leucovorin in patients with resected liver metastases from colorectal cancer.

BACKGROUND: The purpose of the study was to determine the maximum tolerated dose of systemic oxaliplatin (oxal), 5-fluorouracil (5-FU) and leucovorin (LV) that could be administered with hepatic arterial infusion (HAI) of floxuridine (FUDR) and dexamethasone (Dex) in the adjuvant setting after hepatic resection. METHODS: Thirty-five patients with resected liver metastases were entered into a phase I trial using HAI FUDR/Dex with escalating doses of oxal and 5-FU. RESULTS: The initial dose of HAI FUDR was fixed at 0.12 mg/kg x pump volume divided by pump flow rate plus Dex infused over the first 2 weeks of a 5-week cycle. Systemic chemotherapy was delivered on days 15 and 29 with the doses of oxal escalated from 85 to 100 mg/m2 and the 5-FU 48-h continuous infusion doses from 1000 to 2000 mg/m2. The LV dose was fixed at 400 mg/m). Dose-limiting toxic effects were diarrhea, 8.5%, and elevated bilirubin, 8.5%. With a median follow-up of 43 months, the 4-year survival and progression-free survival were 88% and 50%, respectively. CONCLUSIONS: Adjuvant therapy after liver resection with HAI FUDR/Dex plus systemic oxal at 85 mg/m2 and 5-FU by continuous infusion at 2000 g/m2 with LV at 400 mg/m2 is feasible and appears effective. Randomized studies comparing this regimen to systemic FOLFOX are suggested.

Gallbladder cancer (GBC): 10-year experience at Memorial Sloan-Kettering Cancer Centre (MSKCC).

BACKGROUND: The incidence of gallbladder cancer (GBC) in the US is 1.2/100,000. This report examines the patterns of presentation, adjuvant treatment and survival of a large cohort of patients with GBC evaluated at MSKCC over a 10-year period. METHODS: A retrospective analysis of patients referred to MSKCC with a diagnosis of GBC between January 1995 and December 2005 was performed. Patients were identified from the MSKCC cancer registry. Information extracted included, demographics, clinical and pathological stage, surgical management, pathology, adjuvant and palliative therapy, date of relapse, death or last follow-up. Date of diagnosis was defined as date of surgery or biopsy. Survival curves were estimated using the Kaplan-Meier method and compared using the log-rank test. RESULTS: Four hundred thirty-five GBC cases were identified: 285 (65.5%) females,150 (34.5%) males. Median age 67 years (range 28-100). Pathology: 88% adenocarcinoma, 4% squamous, 3% neuroendocrine, 2% sarcoma. 36.6% presented as AJCC Stage IV. 47% were discovered incidentally at laparoscopic cholecystectomy. One hundred thirty-six of these were re-explored, of whom 100 (73.5%) had residual disease. Of those who underwent curative resections (N = 123), 8 (6.5%) received adjuvant chemotherapy, 8 (6.5%) chemoradiation alone and 8 (6.5%) both chemoradiation and systemic chemotherapy. Median overall survival for the cohort was 10.3 months (95% CI 8.8-11.8) with a median follow up of 26.6 months. The median survival for those presenting with stage Ia-III disease was 12.9 months (95% CI 11.7-15.8 months) and 5.8 months (95% CI 4.5-6.7) for those presenting with stage IV disease. Median survival was 15.7 months (95% CI 12.4-18.4) for those discovered incidentally at laparoscopic cholecystectomy. For those who underwent re-exploration, median survival was 14.6 months (95% CI 12.6-18.3) if residual disease was present, and 72 months (95% CI 34 to infinity) if no evidence of disease. The median survival for those who received adjuvant therapy was 23.4 months (95% CI 15.7-47). CONCLUSIONS: GBC is commonly diagnosed incidentally (47%). Re-exploration reveals a high incidence of residual disease (74%). Median survival is better for patients who have no evidence of disease on re-exploration (72 months) compared to those with residual disease detected (P < 0.0001). Overall prognosis is poor. Although we did not observe a survival benefit for those who received adjuvant therapy, the study did not have sufficient power to address this question. In addition, the number of patients who received adjuvant therapy was small with marked heterogeneity in clinical and therapeutic details, precluding any definitive conclusions being drawn. Prospective randomized trials of adjuvant therapy are needed in this disease.

Gallbladder carcinoma.

Although it is the most common cancer of the biliary tree, gallbladder carcinoma remains an uncommon disease. As a result, many clinicians rarely encounter it and there is uncertainty regarding proper management. Resection is the most effective and only potentially curative treatment. Early stage tumors are often curable with a proper resection; however, many patients present late in the course of the disease when surgical intervention is no longer effective. While other treatment modalities are used in patients with advanced disease, there is limited data on efficacy. In many cases, the diagnosis is made after a cholecystectomy has been performed and an incidental tumor is identified in the specimen. In such cases, reoperation and definitive resection is appropriate and effective for patients with invasive lesions.

Rates and patterns of recurrence for percutaneous radiofrequency ablation and open wedge resection for solitary colorectal liver metastasis.

INTRODUCTION: The purpose of this study was to compare rates and patterns of disease progression following percutaneous, image-guided radiofrequency ablation (RFA) and nonanatomic wedge resection for solitary colorectal liver metastases. METHODS: We identified 30 patients who underwent nonanatomic wedge resection for solitary liver metastases and 22 patients who underwent percutaneous RFA because of prior major hepatectomy (50%), major medical comorbidities (41%), or relative unresectability (9%). Serial imaging studies were retrospectively reviewed for evidence of local tumor progression. RESULTS: Patients in the RFA group were more likely to have undergone prior liver resection, to have a disease-free interval greater than 1 year, and to have had an abnormal carcinoembryonic antigen (CEA) level before treatment. Two-year local tumor progression-free survival (PFS) was 88% in the Wedge group and 41% in the RFA group. Two patients in the RFA group underwent re-ablation, and two patients underwent resection to improve the 2-year local tumor disease-free survival to 55%. Approximately 30% of patients in each group presented with distant metastasis as a component of their first recurrence. Median overall survival from the time of resection was 80 months in the Wedge group vs 31 months in the RFA group. However, overall survival from the time of treatment of the colorectal primary was not significantly different between the two groups. CONCLUSIONS: Local tumor progression is common after percutaneous RFA. Surgical resection remains the gold standard treatment for patients who are candidates for resection. For patients who are poor candidates for resection, RFA may help to manage local disease, but close follow-up and retreatment are necessary to achieve optimal results.

Prospective, blinded comparison of helical CT and CT arterial portography in the assessment of hepatic metastasis from colorectal carcinoma.

OBJECTIVE: This prospective blinded comparison of helical CT and helical CT arterial portography aimed to detect liver metastasis from colorectal carcinoma. METHODS AND MATERIALS: 50 patients with colorectal carcinoma were evaluated comparing helical CT with helical CT arterial portography. Each imaging study was evaluated on a 5-point ROC scale by radiologists blinded to the other imaging findings, and the results were compared, with the surgical and pathologic findings as the gold standard. RESULTS: Of the 127 lesions found at pathology identified as metastatic colorectal cancer, helical CT correctly identified 85 (69%) and CT portography 96 (76%). When subgroups with lesions <3 cm (48 patients) and patients with maximum tumor size <3 cm (18 patients) were considered, CT portography was always better than helical CT in terms of sensitivity, specificity, positive predictive value, and negative predictive value. ROC analysis adjusting for multiple lesions per patient revealed significantly greater area under the curve (AUC) for the subgroup of lesions <3 cm (CT-AUC of 77% and CT portography AUC of 81%; P = 0.002). CONCLUSIONS: For identification of large metastases, helical CT and CT portography have similar yield. However, for detection of small liver metastases, CT portography remains superior for lesion detectability.

Treatment of cholangiocarcinoma with oncolytic herpes simplex virus combined with external beam radiation therapy.

Replication-competent oncolytic herpes simplex viruses (HSV), modified by deletion of certain viral growth genes, can selectively target malignant cells. The viral growth gene gamma(1)34.5 has significant homology to GADD34 (growth arrest and DNA damage protein 34), which promotes cell cycle arrest and DNA repair in response to stressors such as radiation (XRT). By upregulating GADD34, XRT may result in greater oncolytic activity of HSV strains deficient in the gamma(1)34.5 gene. The human cholangiocarcinoma cell lines KMBC, SK-ChA-1 and YoMi were treated with NV1023, an oncolytic HSV lacking one copy of gamma(1)34.5. Viral proliferation assays were performed at a multiplicity of infection (MOI, number of viral particles per tumor cell) equal to 1, either alone or after XRT at 250 or 500 cGy. Viral replication was assessed by plaque assay. In vitro cytotoxicity assays were performed using virus at MOIs of 0.01 and 0.1, with or without XRT at 250 cGy and cell survival determined with lactate dehydrogenase assay. Established flank tumors in athymic mice were treated with a single intratumoral injection of virus (10(3) or 10(4) plaque forming units), either alone or after a single dose of XRT at 500 cGy, and tumor volumes measured. RT-PCR was used to measure GADD34 mRNA levels in all cell lines after a single dose of XRT at 250 or 500 cGy. NV1023 was tumoricidal in all three cell lines, but sensitivity to the virus varied. XRT enhanced viral replication in vitro in all cell lines. Combination treatment with low-dose XRT and virus was highly tumoricidal, both in vitro and in vivo. The greatest tumor volume reduction with combination therapy was seen with YoMi cells, the only cell line with increased GADD34 expression after XRT and the only cell line in which a synergistic treatment effect was suggested. In KMBC and SK-ChA-1 cells, neither of which showed increased GADD34 expression after XRT, tumor volume reduction was less pronounced and there was no suggestion of a synergistic effect in either case. Oncolytic HSV are effective in treating human cholangiocarcinoma cell lines, although sensitivity to virus varies. XRT-enhanced viral replication occurs through a mechanism that is not necessarily dependent on GADD34 upregulation. However, XRT-induced upregulation of GADD34 further promotes tumoricidal activity in viral strains deficient in the gamma(1)34.5 gene, resulting in treatment synergy; this effect is cell type dependent. Combined XRT and oncolytic viral therapy is a potentially important treatment strategy that may enhance the therapeutic ratios of both individual therapies.