Biologic mesh spacer placement facilitates safe delivery of dose-intense radiation therapy: A novel treatment option for unresectable liver tumors

INTRODUCTION

Patients with unresectable liver tumors who fail initial treatment modalities have a poor prognosis (<1 yr). Although effective, delivery of high dose radiation therapy to these tumors is limited by proximity of radiosensitive bowel. We have previously reported that placement of a biologic mesh spacer (BMS) can effectively displace the bowel allowing for dose-intense radiation to be delivered with low short-term toxicity. The purpose of this study was to assess and report the long-term safety and oncologic outcomes of this cohort.

METHODS

From 2012 to 2014 seven patients with unresectable hepatic malignancy (6 IHCC, 1 CRLM) underwent BMS (acellular human dermis) placement (2 open, 5 MIS) prior to radiation therapy. Prospective registry data were reviewed for tumor and treatment details, progression, metastasis and survival. RTOG guidelines were used to define radiation toxicities.

RESULTS

Mean patient age was 50.4 years (30-62 years) and 4 patients were male (57.1%). Prior to surgery, all patients had been treated for an average of 12.5 months with surgery, chemotherapy, radiation and/or TACE. After surgery, all patients recovered well and received a mean radiation dose of 76.1 Gy (58.1-100 Gy) over 13-25 fractions. 1 patient received SBRT; 4 fractions, 10 Gy each. Maximum dose delivered was 100 Gy (Biologic Equivalent Dose of 140 Gy, α/β = 10). Mean time to initiation of radiation therapy was 24 days (12-48 days) from surgery. No significant GI toxicity was recorded, and no GI bleeding or ulcers were observed. Mean follow-up after XRT was 18.2 months (5.5-31 months). Three patients had no loco-regional progression of disease. 2 patients had infield progression of liver disease and another had progressive lymphadenopathy. 3 patients developed pulmonary metastasis, at a mean time to distant failure of 3 months. There are 4 survivors over 2-years from surgery.

CONCLUSION

For patients with unresectable liver tumors, placement of a BMS enhances the safety and efficacy of high-dose radiotherapy, providing a survival benefit via delay in time to progression compared to traditional treatments with no significant short or long term GI toxicity.

IV-HCC: Clinical and prognostic implications of plasma IGF-1 and VEGF in patients with hepatocellular carcinoma

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Background: Hepatocellular carcinoma (HCC) is a vascular tumor, derived mainly by vascular endothelial growth factor (VEGF)-mediated angiogenesis. It is always associated with chronic liver disease (CLD) and cirrhosis, which directly affect survival of HCC patients. Insulin-like growth factor-1 (IGF-1) is produced predominantly in the liver, and therefore, CLD is associated with low levels of IGF-1.

Methods: 288 new consecutive patients with HCC were eligible for the study between 2001 and 2008 at M. D. Anderson Cancer Center. Baseline clinicopathologic features, CLIP and BCLC staging, plasma IGF-1 and VEGF levels were available and multivariate Cox regression models and median survival were calculated. Kaplan-Meier curves were used to estimate overall survival and the log-rank test was used to compare survival probabilities in patients with different IGF-1 and VEGF levels. Recursive partitioning was used to determine the optimal cut point for IGF-1 and VEGF, using repeated training/validation samples, each using 2/3 of the data to determine the best cut point and the remaining 1/3 to validate it. Prognostic ability of different molecular staging systems was compared using C-index.

Results: Lower plasma IGF-1 and higher plasma VEGF levels significantly correlated with advanced clinicopathologic parameters and poor overall survival, with an optimal cut point of 26 pg/mL and 450 pg/mL respectively. The combination of low IGF-1 and high VEGF predicts median OS of 2.7 months compared with 19 month for patients with high IGF-1 and low VEGF (p-value=<0.0001), and further refines the prognostic ability of BCLC and CLIP HCC staging systems (p<0.0001).

Conclusions: Molecular classification of HCC using baseline plasma IGF-1 and VEGF significantly correlated with clinical features and survival of HCC patients. Furthermore, integrating IGF-1 and VEGF into HCC staging systems, CLIP and BCLC, significantly enhanced their ability to predict prognosis. It may prove to be useful in designing strategies to personalize treatment approaches to these patients.

No significant financial relationships to disclose.

Dose-escalated external beam radiotherapy in unresectable hepatocellular carcinoma

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Background: Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide. Data regarding the use of external beam radiotherapy is limited in patients from populations without endemic viral hepatitis. We examine the outcomes for patients treated with external beam radiotherapy in the modern era at a single institution.

Methods: A total of 29 patients with localized HCC treated from 2000 to 2009 were reviewed. Patients with metastatic disease at the time of radiation were excluded. Median radiation dose was 50 Gy (range 30-75 Gy) with a median biologically effective dose (BED) of 80.6 (range 60-138.6). Median tumor size at the time of radiation was 5.2 cm (range 2-25 cm).

Results: Median residual tumor following radiation was 80% (range 27%-278%), with a median residual α-fetoprotein of 47% (range 0.8%-8240%). Estimated one-year overall survival (OS) and in-field progression-free survival (PFS) rates for the study population were 56% and 79%, respectively. One year OS in patients treated to a BED <75 was 18% vs. 69% in patients treated to a BED ≥75 (p=0.002). One year in-field PFS rate (60% vs. 88%, p=0.023) and biochemical PFS duration (median 6.5 vs. 1.6 mos., p=0.001) were also significantly improved in patients treated to a BED ≥75. Grade 3 toxicity was seen in only 13.8% of patients.

Conclusions: In a population without endemic viral hepatitis, unresectable HCC demonstrates significant response toexternal beam radiotherapy with minimal toxicity. Furthermore, our findings suggest that increased BED is associated with improved survival and local tumor control.

No significant financial relationships to disclose.

Resection of liver metastases from breast cancer: Effect of timing of surgery and estrogen receptor status on outcome

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Background: The oncologic benefit of resecting liver metastases (LM) in breast cancer patients is unclear. Identifying predictors of improved outcome would be useful in selecting appropriate candidates for surgery.

Methods: From 1997 to 2010, 86 breast cancer patients underwent LM resection. RECIST criteria were used to define the best response to chemotherapy as the optimal response at any time during the course of metastatic disease and the preoperative response to chemotherapy as the response immediately before LM resection. Univariate and multivariate analyses were used to identify predictors of survival.

Results: Sixty-four patients (74%) had primary tumors that were either estrogen receptor (ER) or progesterone receptor (PR) positive. Fifty-three patients (62%) had solitary LM, and 73 patients (85%) had LM smaller than 5 cm. Sixty-five patients (76%) received preoperative chemotherapy, and 10 patients (12%) received 2 or more chemotherapy regimens before LM resection. Only 2 patients (3%) had progressive disease (PD) as a best response to chemotherapy, whereas 19 patients (29%) had PD as preoperative response to chemotherapy (p < 0.001). No perioperative mortality was observed. At a median follow-up of 62 months, the median durations of overall and disease-free survival were 57 and 14 months. Univariate analysis revealed that ER and PR primary tumor status, best response to chemotherapy, and preoperative response to chemotherapy were associated with overall survival after LM resection. On multivariate analysis, an ER-negative primary tumor (p=.009, hazard ratio [HR] = 3.3, 95% confidence interval [CI] =1.4-8.2) and preoperative disease progression (p=.003, HR = 3.8, 95% CI = 1.6-9.2) were independently associated with worse survival after LM resection.

Conclusions: Resection of liver metastases in breast cancer patients with ER positive disease that is responsive to chemotherapy is associated with prolonged survival. Timing of surgery is critical and resection before progression is associated with better outcome.

No significant financial relationships to disclose.

Association of VEGF expression with poor prognosis among patients with low-grade neuroendocrine carcinoma

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Background: Low-grade neuroendocrine carcinomas (LGNET) can arise from neuroendocrine cells throughout the body and have a wide range of aggressiveness. Reliable predictive and prognostic markers of outcome are lacking. Angiogenesis is critical for metastasis and tumor growth beyond a small tumor size and VEGF is a powerful mediator of tumor angiogenesis. Methods: LGNET tissue from 50 patients (24 with local-regional disease, 26 with metastasis) who underwent tumor resection at the University of Texas M.D. Anderson Cancer Center was evaluated for expression VEGF by immunohistochemistry. Chi-square and Fisher’s exact test were used to test the association between study parameters. Kaplan-Meier analysis was used to assess the affect of study parameters on progression free survival (PFS). Results: Strong, weak, and negative VEGF expression was observed in 32%, 54%, and 14% of cases respectively. Larger tumor size was observed among patients with strong VEGF expression. Mean tumor sizes in patients with strong, weak and negative VEGF were 4.8, 2.8, and 2.9 cm. Compared to the group with negative VEGF expression, VEGF (weak/strong) expression was associated with metastasis (14% v 58%; P = .045). The median PFS durations of patients with strong and weak VEGF expression were 29 months and 81 months respectively. With a median follow-up duration of 50 months, the median PFS duration for the group with negative VEGF expression has not been reached. Compared by log rank test VEGF expression was associated with poor PFS (P = .022). Conclusions: This study suggests that tissue VEGF expression is associated with aggressive tumor growth and metastasis among patients with LGNET. VEGF expression may serve as a useful prognostic marker following tumor resection.

No significant financial relationships to disclose.

Toxicity and Efficacy of Concurrent Gemcitabine and Radiotherapy for Locally Advanced Pancreatic Cancer

Gemcitabine has been demonstrated to be a potentradiosensitizer in the laboratory and in the clinic (1-7)and has proven clinical systemic activity to pancreaticcancer. Responses to systemic gemcitabine inpatients with metastatic pancreatic adenocarcinomahave been documented in phase I, phase II, and phaseIII clinical settings (8,9). Moreover, a recent randomizedtrial of gemcitabine vs 5-FU as first-linetherapy in patients with advanced pancreatic adenocarcinomademonstrated a modest median survivalbenefit (4.41 vs 5.65 mo,p= 0.0025) for those patientswho received gemcitabine compared to those whoreceived 5-FU (10). In addition, gemcitabine wasshown to improve cancer-related symptoms and performancestatus as assessed by a quantitative clinicalbenefit scale in both untreated and previouslytreated patients with metastatic adenocarcinoma ofthe pancreas (10,11). Based on these data, the FDAapproved gemcitabine as a first-line agent for patientswith advanced adenocarcinoma of the pancreas.

Effective pelvic symptom control using initial chemoradiation without colostomy in metastatic rectal cancer

PURPOSE

To assess pelvic chemoradiotherapy (CXRT) without colostomy as a component of the multidisciplinary management of patients presenting with metastatic rectal cancer.

METHODS AND MATERIALS

Eighty patients with synchronous distant metastases from rectal cancer were treated with initial CXRT. Hypofractionated radiotherapy was administered usually with concurrent 5-FU (92%, 300 mg/m(2)/day, M-F). Three-field belly-board technique was used in 89%. Group 1 had CXRT alone (n = 55). Group 2 (n = 25) patients were selected for primary disease resection, and sometimes HAI chemotherapy (n = 10) or hepatic resection (n = 5). Subsequently, 78% received systemic chemotherapy.

RESULTS

Symptoms from primary tumor resolved in 94%. Endoscopic complete clinical response rate was 36%. Two-year survival (11% vs. 46%, p < 0.0001) and symptomatic pelvic control (PC, 81% vs. 91%, p = 0.111) were higher in Group 2, but colostomy-free rate (CFR) was lower (79% vs. 51% p = 0.02). CFR was 87% in Group 1 patients managed initially without fecal diversion (n = 50). Examining all patients using multivariate analysis, pelvic pain at presentation (p < 0.00001), BED (biologic equivalent dose at 2 Gy/fraction) < 35 Gy (p = 0.077), and poor differentiation (0.079) predicted worse PC. Poor differentiation (p = 0.017) and selection for CXRT alone (p < 0.0001) predicted worse survival. There were 4 RTOG of Grade 3 or greater acute complications, 5 severe perioperative complications, and no significant late treatment-related complications.

CONCLUSION

Durable PC can be safely achieved without colostomy in most patients presenting with primary rectal cancer and synchronous systemic metastases using hypofractionated pelvic chemoradiation. A BED greater than 35 Gy is recommended. Selected patients appear to benefit from resection of primary disease. Higher doses should be investigated in patients with pelvic pain.

Prospective trial of preoperative concomitant boost radiotherapy with continuous infusion 5-fluorouracil for locally advanced rectal cancer

RATIONALE

To evaluate the response to a concomitant boost given during standard chemoradiation for locally advanced rectal cancer.

METHODS AND MATERIALS

Concomitant boost radiotherapy was administered preoperatively to 45 patients with locally advanced rectal cancer in a prospective trial. Treatment consisted of 45 Gy to the pelvis with 18 mV photons at 1.8 Gy/fraction using a 3-field belly board technique with continuous infusion 5FU chemotherapy (300mg/m(2)) 5 days per week. The boost was given during the last week of therapy with a 6-hour inter-fraction interval to the tumor plus a 2-3 cm margin. The boost dose equaled 7.5 Gy/5 fractions (1.5 Gy/fraction); a total dose of 52.5 Gy/5 weeks was given to the primary tumor. Pretreatment tumor stage, determined by endorectal ultrasound and CT scan, included 29 with T3N0 [64%], 11 T3N1, 1 T3Nx, 2 T4N0, 1 T4N3, and 1 with TxN1 disease. Mean distance from the anal verge was 5 cm (range 0-13 cm). Median age was 55 years (range 33-77 years). The population consisted of 34 males and 11 females. Median time of follow-up is 8 months (range 1-24 months).

RESULTS

Sphincter preservation (SP) has been accomplished in 33 of 42 (79%) patients resected to date. Three patients did not undergo resection because of the development of metastatic disease in the interim between the completion of chemoradiation (CTX/XRT) and preoperative evaluation. The surgical procedures included proctectomy and coloanal anastomosis (n = 16), low anterior resection (n = 13), transanal resection (n = 4). Tumor down-staging was pathologically confirmed in 36 of the 42 (86%) resected patients, and 13 (31%) achieved a pathologic CR. Among the 28 tumors (67%) located <6 cm from the anal verge, SP was accomplished in 21 cases (75%). Although perioperative morbidity was higher, toxicity rates during CTX/XRT were comparable to that seen with conventional fractionation. Compared to our contemporary experience with conventional CTX/XRT (45Gy; 1.8 Gy per fraction), improvements were seen in SP (79% vs. 59%; p = 0.02), SP for tumors <6 cm from the anal verge (75% vs. 42%; p = 0.003), and down-staging (86% vs. 62%; p = 0.003).

CONCLUSION

The SP rate with concomitant boost radiation has been highly favorable with rates of response which are higher than those previously reported for chemoradiation without administration of a boost. Further evaluation of this radiotherapeutic strategy appears warranted.

Mirizzi syndrome: A rare cause of obstructive jaundice

Mirizzi syndrome is a rare cause of bile duct obstruction secondary to extrinsic compression of the hepatic duct by stones impacted in the cystic duct or infundibulum of the gallbladder. The suspicion of Mirizzi syndrome primarily relies on radiographic means such as ultrasound, computed tomography and cholangiography. The recognition of this rare syndrome is crucial in developing the proper treatment approach. We present 3 cases of Mirizzi syndrome and a review of the literature pertaining to the diagnosis and treatment of this rare cause of obstructive jaundice.