Long-term outcomes with neoadjuvant chemotherapy with or without stereotactic body radiation therapy in patients with borderline resectable and locally advanced pancreatic adenocarcinoma

443

Background: Patients (pts) withborderline resectable pancreatic cancer (BRPC) or locally advanced pancreatic cancer (LAPC) are at high risk of margin positive resection with upfront surgery. Pre-operative stereotactic body radiation therapy (SBRT) may help sterilize vascular margins, but its additive benefit beyond multi-agent chemotherapy (CTX) is unclear. We report on long-term outcomes from a high-volume institution of BRPC/LAPC pts who were reviewed by a multidisciplinary team and explored after either multi-agent CTX alone or multi-agent CTX followed by SBRT. Methods: Consecutive BRPC/LAPC pts diagnosed 2011-2016 who underwent resection following CTX alone or CTX followed by 5-fraction SBRT (CTX-SBRT) were retrospectively reviewed. Baseline demographic, clinical, and treatment factors were compared between cohorts, and survival analysis was conducted to compare pathologic and survival outcomes. Results: Of 199 pts, 77 received CTX alone and 122 received CTX-SBRT. There was no significant difference between cohorts in age, gender, performance status, tumor location, CA19-9 at diagnosis, or post-CTX CA19-9 values (all p > 0.05). The CTX-SBRT cohort had a higher proportion of pts with LAPC as compared to the CTX cohort (53% vs 22%, p< 0.001). Modified FOLFIRINOX (mFFX) was administered to 55% of pts, while 70% of pts received either mFFX or gemcitabine/abraxane, with no difference between cohorts. Duration of CTX was longer in the CTX-SBRT cohort as compared to the CTX cohort (median 4.6 vs. 2.9 mos, p= 0.03), but adjuvant CTX was not given as often in the CTX-SBRT arm (60.4% vs. 86.4%, p= < 0.001). Notably, 30% of the CTX cohort also received adjuvant chemoradiation. Pathologic response was significantly improved in the CTX-SBRT cohort vs the CTX cohort, specifically negative margins (92% vs 70%, p< 0.001), node negative (59% vs. 42%, p< 0.001), and pathologic complete response (7% vs. 0%, p= 0.02). On multivariable analysis, after controlling for prognostic factors, CTX-SBRT remained significantly associated with margin negative resection ( p< 0.001). Despite having more advanced stage and less adjuvant therapy administration in the CTX-SBRT cohort, there was no significant difference in overall survival after surgery (median OS: 24.6 vs. 22.2 mo, p= 0.79), local progression free survival (14.0 vs. 13.6 mo, p= 0.33), or distant metastasis free survival (16.4 vs. 11.8 mo, p= 0.33). Conclusions: Despite more advanced disease at presentation, BRPC/LAPC pts treated with CTX-SBRT were more likely to undergo margin negative resection and experienced similar survival outcomes, as compared to CTX alone. More data are needed to refine which patients benefit from neoadjuvant SBRT and how RT administration can be optimized to impact survival outcomes.

Long-term outcomes of a prospective single institution study with multiagent chemotherapy and stereotactic body radiation therapy in locally advanced or recurrent pancreatic adenocarcinoma

440

Background: We previously reported a multi-center study in which gemcitabine and stereotactic body radiation therapy (SBRT) were shown to be safe with outcomes comparable to chemoradiation in locally advanced pancreatic cancer (LAPC). This prospective clinical trial was developed to evaluate the efficacy of adding SBRT to multi-agent chemotherapy in LAPC. Herein, we report on the long-term survival outcomes. Methods: From 2012 to 2015, 48 patients (pts) were prospectively enrolled after multidisciplinary evaluation at a single high-volume pancreatic center. Pts received multi-agent chemotherapy (CTX) with modified mFOLFIRINOX (mFFX) or gemcitabine/abraxane followed by 5 fractions of SBRT (median 33 Gy; range, 25-33 Gy). At the time of fiducial placement, biopsies were obtained and DNA extracted for targeted sequencing using MSK-IMPACT. Kaplan-Meier curves were generated to compare survival outcomes by sub-group. Multivariate analysis (MVA) was performed to identify factors prognostic for survival. Results: 44 pts (91.7%) had LAPC disease and 4 (8.3%) had locally recurrent disease. The median follow-up interval was 21.5 months (mo) from diagnosis. CTX consisted of mFFX in 25 pts (52.1%) with 24 pts (50.0%) receiving therapy for a duration ≥4 mo. Of 44 pts with LAPC, 15 (34.1%) were surgically explored, and 11 (73.3%) achieved a margin-negative resection. From diagnosis and after completion of SBRT, respectively, the median overall survival (OS) was 21.6 (95% CI 16-29.7 mo) and 14.6 mo (95% CI: 11.6-23.0 mo); median progression free survival (PFS) was 13.2 (95% CI 11.9-18.1mo) and 6.4 mo (95% CI: 5-12.7 mo); median local PFS (LPFS) was 23.9 (95% CI 18.9-56.9 mo) and 15.8 mo (95% CI: 12.9-27.6 mo); and median distant metastasis free survival (DMFS) was 18.4 (95% CI 12.6-29.3 mo) and 8.5 mo (95% CI: 6.3-17.2 mo). Resected pts experienced better DMFS at 1-year (78% vs. 34%, p= 0.004) with an improved trend for 1-year OS (73% vs. 52%, p= 0.331). If CTX duration was ≥4 mo, 1-year OS (75% vs. 42%, p= 0.018), PFS (50% vs. 21%, p= 0.022), and DMFS (72% vs. 29%, p= 0.031) were significantly improved. In 44 LAPC pts, MVA confirmed ≥4 mo duration of CTX was associated with OS, PFS, and DMFS. Surgical resection was associated with improved DMFS, and CA19-9 level prior to SBRT was associated with PFS and LPFS. The most common mutations detected from biopsy specimens were KRAS (64.3%) , TP53 (50%), and SMAD4 (16.7%). Conclusions: In a prospective trial of pts with LAPC receiving multiagent CTX and SBRT, clinical outcomes were improved with longer durations of CT ( > 4 mo). A high proportion of LAPC pts underwent margin negative resection with favorable outcomes. Future studies should focus on which pts are most likely to benefit from SBRT and surgery following multiagent CTX. In pts who cannot undergo resection, escalated doses of SBRT may be indicated. Clinical trial information: NCT01781728.

Survival Outcomes of Adjuvant Chemotherapy Combined With Radiation Versus Chemotherapy Alone After Pancreatectomy for Distal Pancreatic Adenocarcinoma: A Single-Institution Experience

OBJECTIVE

We evaluated survival outcomes in patients with distal pancreatic ductal adenocarcinoma (D-PDAC) after distal pancreatectomy (DP) and adjuvant chemotherapy or chemoradiation.

METHODS

A retrospective analysis of patients who underwent DP for D-PDAC from 2000 to 2015 at the Johns Hopkins Hospital was performed. Demographics, baseline risk factors, and type of adjuvant treatment were assessed for associations with overall survival (OS) and disease-free survival (DFS). Comparisons were made with log-rank tests and Cox proportional hazards regression models.

RESULTS

A total of 294 patients underwent DP for D-PDAC. Of these, 105 patients were followed at the Johns Hopkins Hospital. Forty-five patients received chemotherapy only and 60 patients received chemoradiation. The median OS with chemoradiation was 33.6 months and 27.9 months (P = 0.54) with chemotherapy only. The median DFS was 15.3 months with chemoradiation and 19.8 months with chemotherapy only (P = 0.89). Elevated carbohydrate antigen 19-9, stage II to III disease, splenic vein involvement, and vascular invasion were significant risk factors in multivariate analyses.

CONCLUSIONS

In this retrospective analysis, there were no significant differences in OS or DFS with chemoradiation compared with chemotherapy alone after DP in patients with D-PDAC.

Gastric cancer following pancreaticoduodenectomy: Experience from a high-volume center and review of existing literature

Background

Prolonged survival of patients after pancreaticoduodenectomy can be associated with late complications due to altered gastrointestinal anatomy. The incidence of gastric cancer is increasingly reported. We set out to examine our experience with gastric cancer as a late complication after pancreaticoduodenectomy with a focus on incidence, risk factors, and outcomes.

Methods

We queried our prospectively collected institutional database for patients that developed gastric cancer after pancreaticoduodenectomy and conducted a systematic review of the literature.

Results

Our database revealed 6 patients who developed gastric cancer following pancreaticoduodenectomy, presenting with a mean age of 62.2 years and an even sex distribution. All of those patients underwent pancreaticoduodenectomy for malignant indications with an average time to development of metachronous gastric cancer of 8.3 years. Four patients complained of gastrointestinal discomfort prior to diagnosis of secondary malignancy. All of these cancers were poorly differentiated and were discovered at an advanced T stage (≥ 3). Only half developed at the gastrointestinal anastomosis. Four underwent surgery with a curative intent, and 2 patients are currently alive (mean postgastrectomy survival = 25.5 months). In accordance with previous literature, biliopancreatic reflux from pancreaticoduodenectomy reconstruction, underlying genetic susceptibility, and adjuvant therapy may play a causative role in later development of gastric cancer.

Conclusion

Long-term survivors after pancreaticoduodenectomy who develop nonspecific gastrointestinal complaints should be evaluated carefully for complications including gastric malignancy. This may serve as an opportunity to intervene on tumors that typically present at an advanced stage and with aggressive histology.

Circulating tumor DNA as a potential marker of adjuvant chemotherapy benefit following surgery for localized pancreatic cancer

BACKGROUND

In early-stage pancreatic cancer, there are currently no biomarkers to guide selection of therapeutic options. This prospective biomarker trial evaluated the feasibility and potential clinical utility of circulating tumor DNA (ctDNA) analysis to inform adjuvant therapy decision making.

MATERIALS AND METHODS

Patients considered by the multidisciplinary team to have resectable pancreatic adenocarcinoma were enrolled. Pre- and post-operative samples for ctDNA analysis were collected. PCR-based-SafeSeqS assays were used to identify mutations at codon 12, 13 and 61 of KRAS in the primary pancreatic tumor and to detect ctDNA. Results of ctDNA analysis were correlated with CA19-9, recurrence-free and overall survival (OS). Patient management was per standard of care, blinded to ctDNA data.

RESULTS

Of 112 patients consented pre-operatively, 81 (72%) underwent resection. KRAS mutations were identified in 91% (38/42) of available tumor samples. Of available plasma samples (N = 42), KRAS mutated ctDNA was detected in 62% (23/37) pre-operative and 37% (13/35) post-operative cases. At a median follow-up of 38.4 months, ctDNA detection in the pre-operative setting was associated with inferior recurrence-free survival (RFS) [hazard ratio (HR) 4.1; P = 0.002)] and OS (HR 4.1; P = 0.015). Detectable ctDNA following curative intent resection was associated with inferior RFS (HR 5.4; P < 0.0001) and OS (HR 4.0; P = 0.003). Recurrence occurred in 13/13 (100%) patients with detectable ctDNA post-operatively, including in seven that received gemcitabine-based adjuvant chemotherapy.

CONCLUSION

ctDNA studies in localized pancreatic cancer are challenging, with a substantial number of patients not able to undergo resection, not having sufficient tumor tissue for analysis or not completing per protocol sample collection. ctDNA analysis, pre- and/or post-surgery, is a promising prognostic marker. Studies of ctDNA guided therapy are justified, including of treatment intensification strategies for patients with detectable ctDNA post-operatively who appear at very high risk of recurrence despite gemcitabine-based adjuvant therapy.

Validation of a nomogram to predict the risk of cancer in patients with intraductal papillary mucinous neoplasm and main duct dilatation of 10 mm or less

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) is premalignant pancreatic lesion. International guidelines offer limited predictors of individual risk. A nomogram to predict individual IPMN malignancy risk was released, with good diagnostic performance based on a large cohort of Asian patients with IPMN. The present study validated a nomogram to predict malignancy risk and invasiveness of IPMN using both Eastern and Western cohorts.

METHODS

Clinicopathological and radiological data from patients who underwent pancreatic resection for IPMN at four centres each in Eastern and Western countries were collected. After excluding patients with missing data for at least one malignancy predictor in the nomogram (main pancreatic duct diameter, cyst size, presence of mural nodule, serum carcinoembryonic antigen and carbohydrate antigen (CA) 19-9 levels, and age).

RESULTS

In total, data from 393 patients who fit the criteria were analysed, of whom 265 were from Eastern and 128 from Western institutions. Although mean age, sex, log value of serum CA19-9 level, tumour location, main duct diameter, cyst size and presence of mural nodule differed between the Korean/Japanese, Eastern and Western cohorts, rates of malignancy and invasive cancer did not differ significantly. Areas under the receiver operating characteristic (ROC) curve values for the nomogram predicting malignancy were 0·745 for Eastern, 0·856 for Western and 0·776 for combined cohorts; respective values for the nomogram predicting invasiveness were 0·736, 0·891 and 0·788.

CONCLUSIONS

External validation of the nomogram showed good performance in predicting cancer in both Eastern and Western patients with IPMN lesions.

Perioperative outcomes and long-term quality of life after total pancreatectomy

BACKGROUND

Total pancreatectomy is required to treat diseases involving the entire pancreas, and is characterized by high morbidity rates and impaired long-term quality of life (QoL). To date, risk factors associated with perioperative and long-term outcomes have not been determined fully.

METHODS

Data from patients undergoing total pancreatectomy between 2000 and 2014 at two high-volume centres were analysed retrospectively to assess risk factors for major surgical complications. Short Form (SF) 36, European Organisation for Research and Treatment of Cancer QLQ-PAN26 and Audit of Diabetes Dependent questionnaires, as well as an original survey were used to investigate factors influencing QoL.

RESULTS

A total of 329 consecutive patients underwent total pancreatectomy in the two centres. Overall, total pancreatectomy was associated with a morbidity rate of 59·3 per cent and a 30-day mortality rate of 2·1 per cent. Age over 65 years and long duration of surgery (more than 420 min) were independently associated with major complications (at least Clavien-Dindo grade III). QoL analysis was available for 94 patients (28·6 per cent) with a median follow-up of 63 (i.q.r. 20-109) months; the most common indication for total pancreatectomy in these patients was intraductal papillary mucinous neoplasms (46 per cent). Both physical (PCS) and mental (MCS) component summary scores of SF-36® were lower after total pancreatectomy compared with scores for a normative population (P = 0·020 and P < 0·001 respectively). Linear regression analysis showed that young age, abdominal pain and worse perception of body image were negatively associated with the PCS, whereas diabetes, sexual satisfaction and perception of body image affected MCS.

CONCLUSION

Total pancreatectomy can be performed with acceptable morbidity and mortality rates. Older patients had a higher risk of postoperative complications but reported better QoL than younger patients.

Variation in the surgical management of locally advanced pancreatic cancer

4122

Background: Recent reports suggest patients with locally advanced pancreatic cancer (LAPC) may become candidates for curative resection following neoadjuvant therapy, with encouraging survival outcomes. Yet the optimal management approach for LAPC remains unclear. We sought to investigate surgeon preferences for the management of patients with LAPC. Methods: An extensive electronic survey was systematically distributed by email to an international cohort of pancreas surgeons. Data collected included surgeon practice characteristics, preferences for staging and management, and 6 clinical vignettes (with detailed videos of post-neoadjuvant arterial and venous imaging) to assess attitudes regarding eligibility for surgical exploration. Results: A total of 150 eligible responses were received from 4 continents. Median duration in practice was 12 years (IQR 6-20) and 75% respondents work in a university setting. Most (84%) are considered high volume, 33% offer a minimally-invasive approach, and 48% offer arterial resection in selected patients. A majority (70%) always recommend neoadjuvant chemotherapy, and 62% prefer FOLFIRINOX. Preferences for duration of neoadjuvant therapy varied widely: 39% prefer ≥2 months, 41% prefer ≥4 months, and 11% prefer 6 months or more. Forty-one percent frequently recommend neoadjuvant radiation, and 51% prefer standard chemoradiotherapy. Age ≥80 years and CA 19-9 of ≥1000 U/mL were commonly considered contraindications to exploration. In 5 clinical vignettes of LAPC, the proportion of respondents that would offer exploration following neoadjuvant varied extensively, from 15% to 54%. In a vignette of oligometastatic pancreatic liver metastases, 32% would offer exploration if a favorable biochemical and imaging response to therapy is observed. Conclusions: In an international cohort of high volume pancreas surgeons, there is substantial variation in attitudes regarding staging preferences and surgical management of LAPC. These results underscore the importance of coordinated multi-disciplinary care, and suggest an evolving concept of “resectability.” Patients and their oncologists should have a low threshold to consider a second opinion for the surgical management of LAPC, if desired.

Higher Tumor Burden Neutralizes Negative Margin Status in Hepatectomy for Colorectal Cancer Liver Metastasis

OBJECTIVE

The aim of this study was to examine if the prognostic significance of margin status in hepatectomy for colorectal cancer liver metastasis (CRLM) varies for different levels of tumor burden because hepatectomy indications for CRLM have been recently expanded to include patients with a higher tumor burden in whom achieving an R0 resection is difficult.

METHODS

Clinicopathological variables in an exploration cohort of 290 patients receiving hepatectomy in Japan for CRLM were investigated. R0 resection was defined as a margin width > 0 mm. Tumor burden was assessed using the recently introduced Tumor Burden Score (TBS), which was calculated as TBS² = (maximum tumor diameter in cm)² + (number of lesions)². The principal findings were validated using a cohort from the United States.

RESULTS

R1 resection rates significantly increased as TBS increased: 4/86 (4.7%) in patients with TBS < 3, 29/171 (17.0%) in patients with TBS ≥ 3 and < 9, and 9/33 (27.3%) in patients with TBS ≥ 9 (p < 0.001). R0 resection was significantly superior to R1 resection in patients with TBS ≥ 5; however, this was not the case for TBS ≥ 6, as confirmed by both univariate and multivariate analyses. Furthermore, prehepatectomy chemotherapy was associated with significantly improved survival for patients with TBS ≥ 8. Analysis of the validation cohort yielded similar results.

CONCLUSIONS

R0 resection appeared to have a positive impact on prognosis among patients with low tumor burden; however, this was not the case for patients with high tumor burden. As such, systemic treatment, in addition to surgery, may be central to achieving satisfactory outcomes in the latter patient population.

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.

Microsatellite instability in resectable colorectal liver metastasis: An international multi-institutional analysis

220

Background: Microsatellite instability (MSI) is associated with favorable prognosis and distinct response to chemotherapy and immunotherapy for non-metastatic colorectal cancer (CRC). However, studies suggest that MSI may have minimal prognostic impact for widely metastatic CRC. Whether MSI is prognostic for the subset of patients with resectable colorectal liver metastases (CRLM) remains unknown. In this study, we analyze the impact of MSI status on patients with CRLM in the largest cohort reported to date. Methods: Patients who underwent curative-intent resection for CRLM between 2003 and 2017 in five participating tertiary centers and had available data on MSI status were included. Standard clinicopathologic and outcome data were collected. Survival was calculated using Kaplan-Meier analysis. Results: A total of 332 patients who met inclusion criteria were identified, of which 198 (59.6%) were male and 133 (40.7%) had rectal primary tumors. Sixteen patients (4.8%) were MSI positive. The majority of patients had T3 tumors (n = 193; 61.3%) and lymph node metastasis were present in 202 patients (64.5%). The median number of hepatic lesions was 1 [inter-quartile range (IQR):1-3] and median tumor diameter was 2.0 cm (1.2-3.5). Extrahepatic disease was present in 51 (15.7%) patients. Preoperative chemotherapy was administered to 220 (68.8%) patients. Of note, data on KRAS mutation status were available for the majority of the patients (95.5%). Baseline characteristics were similar between MSI positive and negative patients. At a median follow-up of 22.1 months, 154 (47.5%) patients experienced disease recurrence and 70 (21.1%) died. Importantly, neither disease-free survival (DFS, p = 0.168) nor overall survival (OS) were associated with MSI status (p = 0.759). Conclusions: MSI status did not appear to impact survival for patients with resectable CRLM. Additional research in larger cohorts from additional participating institutions is currently underway to assess these preliminary findings.

Phase II study of GM-CSF secreting allogeneic pancreatic cancer vaccine (GVAX) with PD-1 blockade antibody and stereotactic body radiation therapy (SBRT) for locally advanced pancreas cancer (LAPC)

TPS4154

Background: Optimal treatment strategy beyond systemic chemotherapy for LAPC remains undefined. SBRT improves local control, but distant metastasis free survival (DMFS) is only 7.7 months. Checkpoint inhibitors are poor monotherapies in pancreas cancer, but may be primed by SBRT via absocopal effect and GVAX, which induces novel lymphoid infiltrates and increased effector T-cells in tumor microenvironment. Methods: This is a single-arm, single-institution, open-label study for pts with LAPC. Eligibility: surgically unresectable LAPC, predominant adenocarcinoma at diagnosis, with ECOG 0-1, who remain metastases free after 4-8 cycles of FOLFIRINOX or gemcitabine/abraxane based-chemotherapy. Exclusion: those off chemotherapy > 49 days prior to study treatment, prior immunotherapy, active immunosuppressive use, autoimmune disease, HIV, HBV, or HCV infection, and non-oncology vaccines within 28 days of study treatment. Pts receive cyclophosphamide (200mg/m2 IV) and pembrolizumab (200mg IV) on day 1, followed by GVAX (six intradermal injections) on day 2 every three weeks for two cycles, with cycle 2 initiating concurrently with five days of SBRT. If non-metastatic, pts undergo surgical resection, nano-knife, or EUS guided biopsy (if non-surgical). Pts receive two further cycles of chemotherapy, and if remain free of metastases, receive q3 week cyclophosphamide, pembrolizumab, and GVAX for six cycles, then are monitored for two years. The primary endpoint is DMFS. Secondary endpoints include overall survival, surgical resectability, pathologic response, quality of life, and toxicity. Exploratory objectives of peripheral antigen specific t-cell responses, and changes in immune parameters of tumor microenvironment. 11 of 54 pts have been enrolled since July 2016. Clinical trial information: NCT02648282.

Potential role of circulating tumor DNA (ctDNA) in the early diagnosis and post-operative management of localised pancreatic cancer

4101

Background: Pancreatic cancer remains a devastating disease, with the diagnosis typically being made late. ctDNA has shown promise as a screening test for various tumor types. The detection of ctDNA post curative intent surgery has been associated with a high risk of recurrence in multiple solid tumors. We explored the potential of ctDNA to improve pancreatic cancer outcomes. Methods: Data from separate US and Australian series were combined. Plasma samples were collected prior to surgery in both studies and post-operative samples were collected in Australia from cases undergoing curative intent surgery. Clinicians were blinded to ctDNA results and adjuvant therapy was at clinician discretion. Tissue samples from both series were analyzed at Johns Hopkins University. Next generation sequencing was used to search for somatic KRAS mutations in the primary tumors and in cell-free DNA in the plasma. Clinico-pathologic, treatment and outcome data were collected. Results: 119 pts had a ctDNA sample at diagnosis (median age 67 years, 56.3% male). Sixty six pts (55.5 %) had detectable ctDNA, including 3/7 (42.9%) with stage I disease, 54/99 (54.5%) with stage II disease, 4/8 (50%) with stage III disease and 5/5 (100%) with metastases. Specific codon 12 KRAS (G12D, G12V or G12R) mutations were identified in the tumor tissue of 12/16 (75%) patients who had a ctDNA sample collected post-surgery. At a median follow-up of 15.2 months, 7/12 (58.3%) pts had recurred, including 3/8 (37.5%) with no detectable ctDNA and 4/4 (100%) with detectable ctDNA post-surgery (HR 4.9, p = 0.04). Detectable ctDNA post-surgery was significantly associated with poor overall survival (HR 6.93, p = 0.006), with a median of 8 months for pts with detectable ctDNA. Conclusions: ctDNA shows promise as a pancreatic cancer screening test, being detectable in a high proportion of pts with early stage disease. The detection of ctDNA post operatively predicts a very high risk of recurrence. The clinical utility of ctDNA to guide adjuvant therapy decision making, and its potential as a real-time marker of treatment effect, are being explored in further studies. Clinical trial information: ACTRN12612000763842.

Survival outcomes of adjuvant chemotherapy combined with radiation versus chemotherapy alone following pancreatectomy for distal pancreatic adenocarcinoma: Single institution experience

388

Background: There is limited data of survival following distal pancreatectomy and adjuvant therapy in patients with distal pancreatic adenocarcinoma. This study aimed to evaluate the survival following combined modality (chemo-radiation and chemotherapy) compared to chemotherapy alone following distal pancreatectomy (DP). Methods: Patients who underwent DP for adenocarcinoma of the body or tail of the pancreas between the years 2000 and 2015 at Johns Hopkins were included. Comparison analysis was performed between patients who received combined modality versus chemotherapy alone. Kaplan- Meier curve was used to estimate the median overall survival (OS) and the disease free survival (DFS) at 1, 3 and 5 years after pancreatectomy. Results: A total of 294 patients underwent DP at our institution. Patients were excluded if adjuvant therapy was not administered, developed metastasis prior to adjuvant therapy, had stage IV disease at the time of surgery, received neoadjuvant therapy or had inadequate follow up at our institution to assess survival outcomes. We included a total of 105 patients, of which 45 patients received chemotherapy alone and 60 patients received combined modality. The two groups were similar with respect to nodal and margin status. Patients treated with combined modality had larger > 3cm tumors (p = 0.02). Median OS with combined modality was 60.6 mo and 50.2 mo with chemotherapy only. DFS was 15.2 mo with combined modality and 17.6 mo with chemotherapy only. There was no significant difference between the groups for OS (p = 0.73) or DFS (p = 0.495). Further analysis showed a trend away from chemoradiation in the recent years. Thirty patients (29%) received multi-agent chemotherapy in the adjuvant setting. A tumor diameter > 3cm was a predictive factor for receiving chemoradiation (chi-square p value 0.02). Conclusions: There is no difference in survival with combined modality compared to chemotherapy alone as adjuvant therapy following DP. All patients in this study received adjuvant therapy. We report a higher survival than previously described which could suggest a different biology for distal tumors.

Impact of stereotactic body radiation therapy on patient-reported quality of life in patients with unresectable or recurrent pancreatic cancer

413

Background: The impact of fractionated stereotactic body radiation therapy (SBRT) on patient-reported quality of life (QOL) and physician-reported toxicity in patients with recurrent or locally advanced pancreatic cancer (PCA) was prospectively evaluated. Methods: Forty-two PCA patients were treated with 25-33 Gy using SBRT in 5 fractions on a single-institution study. Both patient- and physician-reported outcomes were evaluated prior to SBRT and 4-6 weeks post-SBRT. Eight outcomes were consistently evaluated among both groups—performance status, fatigue, pain, anorexia, nausea, vomiting, constipation, and diarrhea. Patient-reported QOL metrics were assessed using a 4-point Likert scale on the EORTC QLQ-C30 and QLQ-PAN26, while physician-reported toxicities were graded using the NCI CTCAE version 4.0. Comparisons between those with paired patient- and physician-reported outcomes collected prior to and 4-6 weeks after SBRT were made using the Wilcoxon signed-rank test. Results: Of the 42 patients currently enrolled onto the study, 29 had both patient- and physician-reported outcomes collected prior to and 4-6 weeks after SBRT. Fifty-five percent were female and 83% were Caucasian. The median age at diagnosis was 65.6 years (range, 40.8-86.6). There was no significant impairment of any of the 8 physician-reported toxicities, nor were significant changes observed in patient-reported overall health (p = 0.66) or QOL (p = 0.18) scores following SBRT. Patients felt less worried about their future health (mean change [mD] = -0.45, p = 0.02), and an improvement in feeling less attractive as a result of disease and treatment reached borderline significance (mD= 0.31, p = 0.09). However, patients felt limited in planning activities in advance (mD= 0.45, p = 0.02) and were more constipated (mD= 0.38, p = 0.01) 4-6 weeks post-SBRT. Conclusions: Although the numbers are small, patients with unresectable or locally recurrent PCA do not appear to suffer any detriment of overall health or QOL after receiving a five-day course of SBRT. Moreover, this regimen may lead to a more optimistic point of view on future health and/or level of physical attraction. Clinical trial information: NCT01781728.

A new immunohistochemistry prognostic score (IPS) for recurrence and survival in pancreatic neuroendocrine tumors (PanNET)

241

Background: We aimed to evaluate the expression and prognostic significance of N-myc downstream-regulated gen-1 (NDRG-1), O6-methylguanine DNA methyltransferase (MGMT) and Pleckstrin homology-like domain family A member 3 (PHLDA-3) by immunohistochemistry (IHC) and methylation analysis in resected pancreatic neuroendocrine tumors (PanNET). Methods: Ninety-two patients with resected primary PanNET and follow-up > 24 months were included in this study. Nuclear staining for MGMT and PHLDA-3 were scored as 0, 1-5%, 6-50% and ≥ 51%; cytoplasmic NDRG-1 staining was scored based on intensity and pattern from 0 to 2. We then grouped IHC scores for MGMT (absent versus any expression); for NDRG-1 (0 versus 1 versus 2) and for PHLDA-3 ( < 50% versus ≥ 51%). Finally, we developed an immunohistochemistry prognostic score (IPS) based on MGMT, NDRG-1 and PHLDA-3 IHC expression to predict disease free survival (DFS) and overall survival (OS). The discriminatory ability of multivariate models combining the IPS and important clinical variables was assessed with Harrel’s c-index (HCI) and a modification of Harrell’s c-index (mHCI). Results: DFS was significantly worse in patients without any expression of MGMT compared with those with any grade of expression (HR: 2.21; 95%CI: 0.97-5.02; p = 0.013), in patients with moderate or high score for NDRG-1 (p = 0.005), and in those with high-expression for PHLDA-3 (HR: 1.94; 95%CI: 1.05,3.6; p = 0.036). A significant difference in OS was observed based on NDRG-1 score (p = 0.013). In multivariate analyses, ki-67 (HR: 2.45; 95% CI: 1.20-5.01; p = 0.01) and IPS (HR: 2.68; 95% CI: 1.60,4.49; p = 0.00018) were independent prognostic factors for DFS, while age (HR: 7.67; 95% CI: 2.14,27.45; p = 0.0017) and IPS (HR: 2.67; 95% CI: 1.11, 6.41; p = 0.03) were independent prognostic factors for OS. HCI for the multivariate DFS and OS models were 0.796 and 0.788, respectively. Conclusions: Our IPS is a useful prognostic biomarker for recurrence and survival in patients following resection for PanNET. Prospective studies are warranted to validate our findings and determine its role for patients’ selection to neo/adjuvant treatments

Stereotactic body radiation therapy and patient-reported quality of life prospectively evaluated in patients with unresectable or recurrent pancreatic cancer

92

Background: The impact of fractionated stereotactic body radiation therapy (SBRT) on patient-reported quality of life (QOL) and physician-reported toxicity in patients with recurrent or locally advanced pancreatic cancer (PCA) was prospectively evaluated. Methods: Forty-two PCA patients were treated with 25-33 Gy using SBRT in 5 fractions on a single-institution study. Both patient- and physician-reported outcomes were evaluated prior to SBRT and 4-6 weeks post-SBRT. Eight outcomes were consistently evaluated among both groups—performance status, fatigue, pain, anorexia, nausea, vomiting, constipation, and diarrhea. Patient-reported QOL metrics were assessed using a 4-point Likert scale on the EORTC QLQ-C30 and QLQ-PAN26, while physician-reported toxicities were graded using the NCI CTCAE version 4.0. Comparisons between those with paired patient- and physician-reported outcomes collected prior to and 4-6 weeks after SBRT were made using the Wilcoxon signed-rank test. Results: Of the 42 patients currently enrolled onto the study, 29 had both patient- and physician-reported outcomes collected prior to and 4-6 weeks after SBRT. Fifty-five percent were female and 83% were Caucasian. The median age at diagnosis was 65.6 years (range, 40.8-86.6). There was no significant impairment of any of the 8 physician-reported toxicities, nor were significant changes observed in patient-reported overall health (p = 0.66) or QOL (p = 0.18) scores following SBRT. Patients felt less worried about their future health (mean change [mD] = -0.45, p = 0.02), and an improvement in feeling less attractive as a result of disease and treatment reached borderline significance (mD= 0.31, p = 0.09). However, patients felt limited in planning activities in advance (mD= 0.45, p = 0.02) and were more constipated (mD= 0.38, p = 0.01) 4-6 weeks post-SBRT. Conclusions: Although the numbers are small, patients with unresectable or locally recurrent PCA do not appear to suffer any detriment of overall health or QOL after receiving a five-day course of SBRT. Moreover, this regimen may lead to a more optimistic point of view on future health and/or level of physical attraction. Clinical trial information: NCT01781728.

Patient- versus physician-reported outcomes in patients enrolled in a prospective study involving stereotactic body radiation therapy in unresectable or recurrent pancreatic cancer

84

Background: Prospective evaluation of correlations between patient- (PROs) and physician-reported outcomes (PhROs) was conducted among a group of patients receiving stereotactic body radiation therapy (SBRT) for recurrent or locally advanced pancreatic cancer (PCA). Methods: Forty-two patients were treated with 25-33 Gy using SBRT in 5 fractions on a single-institution study. Eight outcomes (performance status, fatigue, pain, anorexia, nausea, vomiting, constipation, and diarrhea) were consistently evaluated by patients and providers prior to SBRT and 4-6 weeks post-SBRT. Patient-reported quality of life (QOL) metrics were assessed using the EORTC QLQ-C30 and QLQ-PAN26, while physician-reported toxicities were graded using the NCI CTCAE v4.0.A Pearson’s correlation was used to determine the relationship between PROs and PhROs. Results: Of the 42 enrolled patients, 36 had both PROs and PhROs collected before (median, 2.9 weeks) SBRT. Physician-reported pain, nausea, constipation, and diarrhea did not show a correlation with patient-reported overall health or QOL. Physician-reported fatigue showed a correlation with patient-reported pain (r > 0.5, p < 0.001) and QOL (r > -0.5, p < 0.001) but not fatigue (r < 0.3, p > 0.05). Nausea and constipation were the only PROs that did not correlate with their respective PhROs (nausea, r < 0.3, p > 0.05; constipation, r < 0.5, p = 0.07) or any of the other 7 PhROs. Only 24 had both PROs and PhROs collected 4-6 weeks after (median, 5.1 weeks) SBRT. Vomiting, constipation, and diarrhea were PhROs that demonstrated no correlation with patient-reported overall health or QOL. Physician-reported vomiting did not correlate with patient-reported vomiting (r < 0.3, p > 0.05) or any of the 7 other PROs. The correlation between patient- and physician-reported pain increased from pre- (r > 0.3, p = 0.03) to post- (r > 0.7, p < 0.0001) SBRT. Conclusions: Discrepancies among PROs and PhROs appear to exist in pancreatic-specific outcomes of interest such as constipation and diarrhea. Future health care teams may find it helpful to consider PROs to better manage symptoms and deliver more personalized care. Clinical trial information: NCT01781728.

Surgical outcomes of patients with pancreatic cancer treated with stereotactic body radiation therapy

341

Background: The surgical outcome of patients with borderline resectable or locally advanced pancreatic ductal adenocarcinoma (BRPC/LAPC) treated with stereotactic body radiation therapy (SBRT) is unclear. Methods: A comparative study was performed to determine if surgical outcomes were different among patients receiving neoadjuvant SBRT vs chemoradiation therapy (CRT) vs chemotherapy only. Results: Between 2011 and 2014, 29 patients with BR/LA-PDAC underwent neoadjuvant chemotherapy and SBRT (6.6 Gy x 5 fractions) followed by pancreatectomy. Eighteen of 29 patients (62%) had LAPC. Their outcomes were compared with 82 patients who received neoadjuvant CRT and 26 patients who received neoadjuvant chemotherapy only (Table). When compared to neoadjuvant CRT and chemo only, the neoadjuvant SBRT group had a higher R0 resection rate (90% vs 84% vs 62%, p=0.02) and vascular resection rate (41% vs 13% vs 31%, p=0.005), respectively. Although the vascular resection and complication rates (Clavien grade 3 or above) were higher in the neoadjuvant SBRT group, no in-hospital mortality was encountered. In the SBRT group, the complete pathological response rate (21%) was higher than that of the other groups (4% and 0% respectively, p<0.001). Survival will be updated later as the current median postoperative follow-up is 6 months in the SBRT group. Conclusions: Neoadjuvant chemotherapy and SBRT is associated with improved surgical outcomes and pathologic complete response rates in selected patients with BRPC/LAPC. Longer follow-up is needed to determine its impact on survival. [Table: see text]

Neutrophil-lymphocyte and platelet-lymphocyte ratio in patients after resection for hepato-pancreatico-biliary cancers

378

Background: Neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) may be indicative of the immune response around the time of surgery. We sought to determine whether NLR or PLR were associated with outcomes of patients undergoing surgery for a hepatopancreatico-biliary (HPB) malignancy. Methods: Between 2010-2011, 289 patients who underwent an HPB procedure for a malignant indication were identified. Clinicopathological characteristics, NLR and PLR, as well as short- and long-term outcomes were analyzed. High NLR and PLR were classified using a cut-off value of 3 and 150, respectively, based on ROC analysis. Results: Median patient age was 63 years and 52.3% were female. The majority of tumors were pancreatic in origin (67.2%), while a subset were primary (10.3%) or secondary (22.5%) liver tumors. Patients with low vs. high NLR and PLR had similar baseline characteristics with regard to performance status and tumor stage (all P>0.05). Operative interventions included pancreaticoduodenectomy (55.0%), ≤hemi-hepatectomy (29.1%), or extended hepatectomy (2.4%). Within 90-days of surgery, 143 patients experienced a complication for a morbidity of 49.5% (pancreas: 54.9% vs. liver: 40.0%). Patients with either an elevated NLR (OR=1.72) or PLR (OR=2.15) were at higher risk of a postoperative complication (both P<0.05). Among patients with a pancreatic, primary or secondary liver tumor, 3-year survival was 38.6%, 43.0%, and 65.0%, respectively. While elevated NLR was not associated with long-term outcome (HR=1.36)(P=0.14), patients with an elevated PLR had a higher risk of death (HR=2.14)(P=0.01). Conclusions: Patients with a high NLR or PLR had an increased risk of a perioperative complication. Elevated PLR was also a predictor of worse survival among patients with HPB malignancy undergoing resection.

Laparoscopic pancreatic surgery

Laparoscopic pancreatectomy may be associated with lower operative morbidity, less postoperative pain, lower wound infection rates, decreased physiological stress, and fewer postoperative hernias and bowel obstructions. In this review, we summarize the current data on laparoscopic and robotic assisted pancreaticoduodenectomy/distal pancreatectomy/central pancreatectomy. We reviewed the indications, the perioperative and oncologic outcomes, and the cost analysis following minimally invasive pancreatic resections. In conclusion, we found minimally invasive approaches to pancreatic resections are feasible, safe, and appear to have comparable oncologic outcomes to the standard open approaches when performed by experienced surgeons at high-volume centers. The potential advantages of a minimally invasive approach to pancreatic surgery, such as reduced blood loss and shorter length of hospital stay, have now been well established. The overall cost of laparoscopic pancreatectomy appears to be similar to that of the open approach.

Stereotactic body radiation therapy for pancreatic cancer: Single institutional experience

328

Background: Stereotactic Body Radiation Therapy (SBRT) is emerging as a possible standard treatment for pancreatic cancer; however, there is limited data to support its efficacy. This study reviews our institution’s experience using SBRT in the treatment of pancreatic cancer (PCA). Methods: Charts of all PCA patients receiving SBRT from January 2010 to June 2013 were retrospectively reviewed. The primary end points were overall survival (OS) and tumor response assessed by RECIST criteria. 95% of the PTV (GTV + 2-3 mm) received a total dose of 20-33 Gy in five fractions (4-6.6 Gy/fraction), with up to 20% heterogeneity allowed. Pre- and post-SBRT chemotherapy regimens included gemcitabine, cisplatin, FOLFIRINOX, 5-FU or paclitaxel. Results: 84 patients received SBRT, with a median follow-up time of 15.3 months. Median age was 66.5 years, 57.1% were male and 65.5% had head tumors. 66 patients received definitive SBRT for locally advanced or borderline resectable PCA, 4 patients were treated with adjuvant SBRT, and 14 received SBRT for treatment of recurrent disease. Median OS from the date of diagnosis for patients receiving definitive radiation was 17.8 mos (95% CI 14.9-20.9).For recurrent patients the median OS from first day of SBRT was 11.8 mos (95%CI 8.3-15.3). In the definitive SBRT group, among patients who were alive and had follow-up scans, the 6 and 12 month local control rate (stable or partial response) based on RECIST criteria was 84.6% and 81.8%, respectively. Five patients underwent surgery following SBRT and all had negative resection margins. Acute toxicity was minimal with most experiencing grade 1 or 2 fatigue and no grade 3/4 acute toxicity. Late grade 3/4 GI toxicity was seen in 5% (4/84) and 1 patient had a grade 5 GI bleed due to direct tumor invasion into the duodenum. Conclusions: Our early results using SBRT in the definitive and recurrent settings show favorable local control, toxicity, and survival when compared to historical outcomes using chemoradiation. Acute and late toxicity was minimal however the optimal dose and fractionation as well as normal tissue dose constraints need to be determined. Integration of SBRT with more aggressive chemotherapy may result in improved outcomes in patients with PCA.

Pre-SBRT metabolic tumor volume and total lesion glycolysis to predict survival in patients with locally advanced pancreatic cancer receiving stereotactic body radiation therapy

189

Background: Though prior studies have demonstrated the prognostic value of pre- and post-treatment positron emission tomography (PET) parameters in other malignancies, the role of PET in pancreatic cancer is yet to be established. We analyzed the prognostic utility of PET for patients with locally advanced pancreatic cancer (LAPC) undergoing fractionated stereotactic body radiotherapy (SBRT). Methods: Thirty-two patients with LAPC received up to 3 doses of gemcitabine, followed by SBRT 6.6 Gy in 5 daily fractions, 33 Gy total, on a prospective clinical trial. All patients received a baseline PET scan prior to SBRT (pre-SBRT PET). Metabolic tumor volume (MTV), total lesion glycolysis (TLG), and maximum and peak standardized uptake values (SUVmax and SUVpeak) on pre-SBRT PET scans were calculated using an in-house software. Disease measurability was assessed at a threshold based on the liver standard uptake value (SUV) using the equation Livermean + (2 * Liversd). Median values of PET parameters were used as cutoffs when assessing their prognostic potential through univariate and multivariate Cox regression analyses. Results: Of the 32 patients in this study, the majority were male (N=19, 59%), 65 years or older (N=21, 66%), and had tumors located in the pancreatic head (N=27, 84%). Twenty-seven patients (85%) received induction gemcitabine prior to SBRT per protocol. Median overall survival for the entire cohort was 18.8 months (95% CI, 15.7-22.0). An MTV of 26.8 cm3 or greater (HR 4.46, 95% CI 1.64 to 5.88, p < 0.003) and TLG of 70.9 cm3 or greater (HR 3.08, 95% CI 1.18 to 8.02, p < 0.021) on pre-SBRT PET scan were associated with inferior overall survival on univariate analysis. Both pre-SBRT MTV (HR 5.13, 95% CI 1.19 to 22.21, p=0.029) and TLG (HR 3.34, 95% CI 1.07 to 10.48, p=0.038) remained independent prognostic factors for overall survival in separate multivariate analyses. Conclusions: Pre-SBRT MTV and TLG yield prognostic information on overall survival in patients with LAPC and may assist in tailoring therapy. Clinical trial information: NCT01146054.

Efficacy of platinum chemotherapy agents in the adjuvant setting for adenosquamous carcinoma of the pancreas

269

Background: Pancreatic adenosquamous carcinoma (PASC) accounts for only 1-4% of exocrine pancreatic cancers and carries a particularly poor prognosis. This retrospective study was performed to determine whether inclusion of a platinum agent as part of adjuvant therapy is associated with improved survival in patients with PASC. Methods: Records of all patients who underwent pancreatic resection at our institution from 1986-2012 were reviewed to identify those with PASC. Multivariable Cox proportional hazards modeling was used to assess for significant associations between patient characteristics and survival. Results: In total, 62 patients with PASC were identified among 5,627 cases (1.1%). Median age was 68 (interquartile range [IQR], 57-77) and 44% were female. Multivariate analysis revealed that among all patients (n=62) the following factors were independently predictive of survival: lack of adjuvant therapy (hazard ratio [HR]=3.558, p=0.0002), positive margin (HR=3.466, p=0.0003), lymph node involvement (HR=3.482, p=0.004), and age (HR=1.030, p=0.035). Among patients who underwent adjuvant therapy (n=39), those who received a platinum agent as part of the adjuvant therapy regimen experienced a longer median survival of 19.1 months (95% CI, 13.8-24.4) compared to 10.7 months (95% CI, 7.9-13.5) for patients who never received a platinum agent (p=0.011, log-rank test). Given this improvement in survival on univariate analysis, a second multivariable model was constructed to elucidate factors associated with survival among patients who received adjuvant therapy in order to confirm the univariate result while controlling for potential confounding risk factors. Backward elimination performed using this second multivariable model revealed that inclusion of a platinum agent in the adjuvant regimen (median survival HR=0.408, p=0.040) and larger tumor diameter (HR=1.259, p=0.047) were independent predictors of survival for this cohort. Conclusions: Addition of a platinum agent to adjuvant regimens for resected PASC should be considered as a means to improve survival among these high risk patients, though collaborative prospective investigation is needed.

Association of ALDH-expressing cancer stem cells with survival in patients with resected pancreatic adenocarcinoma treated with adjuvant chemoradiation

262

Background: We and others have identified aldehyde dehydrogenase (ALDH) activity as a marker of pancreatic cancer stem cells (or tumor-initiating cells). The presence of cancer stem cells (CSCs) has been associated with decreased survival and treatment resistance in pancreatic adenocarcinoma. We investigate the role of ALDH expression in predicting survival and patterns of disease recurrence in patients treated with chemoradiation (CRT) following pancreatectomy. Methods: Tissue microarrays using surgical specimens from 1998 to 2002 were stained for ALDH1 and scored as ALDH-positive or ALDH-negative by two expert pancreatic pathologists blinded to patient outcomes. Physician documentation and radiology reports were used to determine follow-up information. Time to local failure (TLF), time to distant metastases (TDM), progression-free survival (PFS), and overall survival (OS) were analyzed using SPSS software. Results: Previously we found that ALDH expression was associated with worse OS in a cohort of 269 patients with resected pancreatic adenocarcinoma (Rasheed, JNCI 2009). From this cohort, adjuvant treatment information was available for 87 patients with ALDH-negative tumors (48.6%) and 41 patients with ALDH-positive tumors (45.6%). In patients treated with adjuvant CRT, median overall survival was superior in the ALDH-negative cohort vs. the ALDH-positive cohort, 26.3 months vs. 18.2 months (p=0.011). Further, in patients treated with adjuvant CRT, ALDH-negative patients had statistically greater TLF, TDM, and PFS than their ALDH-positive counterparts (see table). On multivariate analysis, ALDH positive tumor staining (HR 1.94, p=0.004) and tumor grade (HR 1.54, p=0.041) predicted lower OS, and ALDH positive tumor staining (HR 1.83, p=0.008), tumor grade (HR 1.52, p=0.038), and tumor size >3 cm (HR 1.65, p=0.023) predicted decreased PFS. Conclusions: This study suggests that adjuvant CRT improves TLF, TDM, PFS, and OS in patients with localized pancreatic adenocarcinoma not enriched with ALDH-expressing CSCs. Laboratory studies will help elucidate the mechanisms of treatment resistance in ALDH expressing CSCs.

Hemoglobin-A1c level to predict for clinical outcomes in patients with pancreatic cancer

4039

Background: An association between diabetes mellitus (DM) and pancreatic ductal adenocarcinoma (PDA) has long been recognized. While long-standing DM may be a risk factor for developing PDA, new-onset DM may be a manifestation of the cancer. Here we assess the role of an objective and quantifiable measure of glucose intolerance, hemoglobin-A1c (HbA1c), in predicting clinical outcomes in PDA. Methods: HbA1c values were prospectively collected on 656 consecutive patients presenting to the Johns Hopkins Pancreas Multidisciplinary Cancer Clinic from 2009-2012. Patients were diagnosed with benign pancreatic disease (BPD) or biopsy-confirmed resectable (R), borderline/locally advanced (BL), or metastatic (M) PDA. Patients with prior treatment for PDA or a history of DM greater than a 1-year were excluded. Univariate Cox regression analyses and multivariable proportional hazards models were used to identify poor prognostic factors for overall survival. Results: Of 284 patients included, 44 had benign disease, 62 R-PDA, 115 BL-PDA, and 63 M-PDA. Patients with malignant disease (R-, BL-, and M-PDA) collectively had higher HbA1c values on average at presentation than patients with BPD (6.1% vs. 5.6%, p<0.001). There was a trend towards higher HbA1c at presentation in patients with advanced PDA (BL and M) compared to patients with R-PDA (6.2% vs. 5.9%, p=0.100); moreover, the proportion of patients with HbA1c levels in the diabetic range (>6.4%) increased with more advanced stage of disease. Among patients with PDA (n=240), univariate analyses showed HbA1c≥6.5, age≥65, ECOG≥1, CA19-9>90, tumor size >3cm, and advanced stage to be significantly associated with inferior survival (all HR>1, p<0.05). After multivariate analysis with backward elimination, all of the above factors except for tumor size >3cm remained in the model for inferior survival. Conclusions: HbA1c level at presentation appears to correlate with disease stage and, moreover, to predict for survival among all stages of PDA. Patients with PDA have significantly higher HbA1c levels at presentation than patients with BPD. This study highlights the potential utility of HbA1c as a screening tool and prognostic factor.

Is successful resection following neoadjuvant radiation therapy for borderline resectable pancreatic cancer dependent on improved tumor-vessel relationships?

4057

Background: Margin-negative (R0) surgical resection is the only potentially curative therapy for pancreatic cancer. For patients deemed borderline resectable (BL), neoadjuvant chemoradiotherapy (NRT) increases the likelihood of subsequent R0 resection and improves overall survival. Prognostic factors for achieving resection following NRT have yet to be clearly identified. Methods: Fifty consecutive patients with BL-PDAC evaluated by a multidisciplinary tumor board who received NRT from 2007-2012 were retrospectively identified. Computed tomography (CT) scans pre- and post-radiation and surgical specimens were centrally reviewed. Results: 29 patients underwent resection following NCRT, while 21 remained unresectable. Between the two groups, age, gender, mean RT dose, and proportion of pancreatic head tumors were not significantly different. Smaller tumor volume and lack of the following factors was associated with selection for resection: superior mesenteric/portal vein encasement (p=0.01), superior mesenteric artery involvement (p=0.02), ascites (p=0.01), and questionable/overt metastases (p=0.01). Notably, celiac artery involvement/encasement, common hepatic artery encasement, and percentage change in tumor volume were not significant predictors of resection (all p>>0.05). Interestingly, tumor volume and degree of individual vessel involvement did not significantly change from scans before and after NCRT (all p>>0.05). Median OS was 22.9 vs.13.0 months in resected and unresected patients, respectively (p<0.001). Of resected patients, 93% had negative margins, 28% had positive nodes, 27% demonstrated <10% viable tumor, and 12% had pathologic complete response at surgery. Dpc4 expression was retained in 68% of specimens with viable tumor. Conclusions: Although the apparent radiographic extent of vascular involvement does not change significantly after NRT, subsequent R0 resection rates are high, nodal involvement is low, and outcomes are similar to resected patients who receive adjuvant therapy. Resection attempts should not be deferred solely based on lack of improvement in tumor-vessel interactions.

Efficacy of platinum chemotherapy agents in the adjuvant setting for adenosquamous carcinoma of the pancreas

e15028

Background: Pancreatic adenosquamous carcinoma (PASC) is a rare morphological subtype of pancreatic adenocarcinoma. PASC accounts for only 1-4% of exocrine pancreatic cancers and carries a particularly poor prognosis. Due to the rarity of PASC, studies of therapies specifically targeting this histopathologic entity are exceedingly limited. Based on efficacy exhibited by platinum agents against squamous carcinoma of other body sites, addition of these agents to adjuvant regimens may benefit patients with PASC. This retrospective study was performed among the largest series of patients with PASC identified to date in order to determine whether addition of platinum agents improves survival. Methods: Records of all patients who underwent pancreatic resection at our institution from 1986-2012 were reviewed to identify those with PASC. Demographic, surgical, pathologic, adjuvant therapy, and survival data were collected. Patients were divided into non-platinum (NPG) and platinum (PG) groups based on whether or not they received a platinum agent as part of adjuvant therapy. Results: In total, 62 patients with PASC were identified among 5,627 cases (1.1%). Fourteen patients received a platinum agent in the adjuvant setting (PG), while 48 did not (NPG). These two groups were comparable in regard to median age (65 vs. 69 yrs, p=0.34), gender (36 vs. 46% female, p=0.50), performance status (78 vs. 79% ECOG 0, p=0.98), histologic grade (86 vs. 77% grade 3, p=0.49), positive resection margins (14 vs. 29%, p=0.26), lymph node involvement (71 vs. 79%, p=0.54), median tumor diameter (4.0 vs. 4.3 cm, p=0.64), and proportion receiving radiotherapy (57 vs. 42%, p=0.31). PG patients received a median of 5.5 cycles (IQR, 3.3-6.0) of platinum chemotherapy, with 10 patients (71%) receiving cisplatin-based regimens and 4 (29%) receiving oxaliplatin-based regimens. PG patients experienced significantly longer median survival (19.1 months, 95% CI 12.8-25.4) compared to NPG patients (9.8 months, 95% CI 7.3-12.4) (p=0.024). Conclusions: Addition of a platinum agent to adjuvant regimens for resected PASC may improve survival among these high risk patients, though collaborative prospective investigation is needed.

Understanding variations in referral patterns and treatment choices for patients with hepatocellular carcinoma

293

Background: Patterns of care of physician specialists may differ for patients with hepatocellular carcinoma(HCC). The extent and reasons underlying possible variations are poorly understood. One source of variation may be disparate referral rates to specialists leading to differences in cancer-directed treatments. Methods: We queried the Surveillance, Epidemiology, and End Results(SEER) linked Medicare database for patients with HCC diagnosed between 1998-2007 who consulted one or more physicians following diagnosis. Visit and procedure records were abstracted from Medicare billing records and factors associated with visiting a specialist and subsequent treatment were examined. Results: 6752 patients with HCC were identified;median age was 73 yrs and the majority was male(66%), White(60%) and from a West geographical region(56%). 1379(20%) patients had early-stage disease. In the six months after diagnosis, referral to a specialist varied considerably (hepatology/gastroenterology-60%; medical oncology-62%; surgery-56%; interventional radiology-33%; radiation oncology-9%). 22% patients saw one specialist, while 39% saw ≥3 specialists. Time between diagnosis and visitation with a specialist varied by sub-specialty (surgery-37 days vs. interventional radiology-55 days;P=0.04). Factors associated with referral to a specialist included younger age(OR=2.13), geographic location(Northeast OR=2.09), and presence of early-stage disease(OR=2.21)(all P<0.05). Among patients with early-stage disease, 77% saw a surgeon, while 50% had a medical oncology consultation. Receipt of therapy among patients with early-stage disease varied (no therapy-30%; surgery-39%; interventional radiology-9%; other-22%). Factors associated with receipt of therapy included younger age(OR=2.82), as well as time to consultation with cancer specialist(OR=1.05)(both P<0.05). Conclusions: Following HCC diagnosis, referral to a specialist varied considerably. Both clinical and non-clinical factors were associated with consultation. Variations in referral to a specialist and subsequent therapy need to be better understood to ensure all HCC patients receive appropriate care.

Duodenal and ampullary carcinoid tumors: Using size to predict necessity for lymphadenectomy

316

Background: The metastatic potential and choice of therapy of duodenal and ampullary carcinoid tumors are poorly understood. We evaluated the local management and outcomes in patients with these uncommon tumors and determined factors predicting risk of nodal involvement. Methods: 117 patients were identified with duodenal or ampullary carcinoid tumors between 1996 and 2012, who were treated in a single high-volume center. Clinicopathologic data and overall survival by local treatment modality were analyzed. Results: Among all patients, 64 (55%) were treated surgically, including 34 (29%) who underwent pancreaticoduodenectomy (PD), 14 (12%) who underwent local resection (partial duodenectomy), and 16 (13.6%) where a carcinoid tumor was found incidentally after PD for another indication. The remaining 53 patients (45%) underwent endoscopic excision. The average tumor size was 1.8 cm (0.1-8.5) and the majority were of duodenal origin (n=93, 80%). Surgical management was more commonly performed for ampullary tumors compared to tumors of duodenal origin (83% vs. 47%, p=0.002), and endoscopic excision was more common with smaller tumors (p=0.001). Most carcinoids were well-differentiated (94%) and 55% were T1/T2. Yet, among the 55 patients in whom lymph nodes were histologically assessed (PD or lymph node sampling), 51% had positive nodes (N+). In addition, on multivariate analysis nodal involvement was strongly associated with tumor size (OR: 9.9, p=0.001). Specifically, tumors larger than 1-cm had positive nodes in more than 70% of cases whereas those ≤1cm had a 5% risk of nodal involvement (1 of 21 patients) (Table). Similar rates of N+ were observed for both duodenal and ampullary carcinoids. With long-term follow-up, only one recurrence was observed (1%). The overall survival was similar among all treatment groups (median=139 months). Conclusions: Lymph node involvement is common in patients with duodenal and ampullary carcinoid tumor, particularly among tumors >1 cm in size. When possible, surgical resection with lymphadenectomy is recommended for such tumors. [Table: see text]

Quality of life in a multicenter phase II trial of neoadjuvant full-dose gemcitabine, oxaliplatin, and radiation in patients with resectable or borderline resectable pancreatic adenocarcinoma

226

Background: Pancreatic cancer remains incurable for the great majority of patients afflicted with the disease. The purpose of this study was to evaluate health related quality of life (HRQoL) following neoadjuvant full dose gemcitabine, oxaliplatin and radiation therapy (30 Gy) for pancreatic adenocarcinoma in a multi-institutional Phase-II trial. Methods: Fifty-seven patients were evaluable for the HRQoL component of this trial that consisted of two cycles of neoadjuvant chemoradiation with gemcitabine and oxaliplatin followed by pancreatectomy and two additional cycles of adjuvant chemotherapy. The effects of therapy on HRQoL were evaluated using: EORTC-C30, EORTC-PAN26 and FACT-HEP. Results: There were 20 patients (35%) with untreated resectable and 37 (65%) with borderline resectable pancreatic cancer. Thirty-nine patients (69%) completed two cycles of preoperative chemotherapy and surgery, 26 (40%) underwent a pancreaticoduodenectomy and 9 (14%) a distal pancreatectomy. Twenty-six patients completed postoperative adjuvant therapy. The median age was 64 (range 42-82); patients younger than 65 had a higher global HRQoL score at 6 months (p=0.046) following the initiation of treatment. There was no difference in the HRQoL according to type of operation performed. EORTC-C30 Global HRQoL remained statistically and clinically unchanged compared to baseline levels at all time-points. FACT-Hep Trial Outcome Index and Total score showed a statistically significant but not clinically meaningful decline following cycle 2 of neoadjuvant treatment (p=0.002 and p=0.004), returning back to baseline levels after 6 months. This may in part be explained by a decrease in the functional (p=0.004) and physical (p=0.001) wellbeing, an increase in diarrhea (p=0.044), digestive symptoms (p=0.037) and an increased fatigue (p<0.001). Conclusions: We report that this neoadjuvant chemoradiation protocol did not have a clinical impact on global HRQoL. Overall this regimen was well tolerated with no negative effect on quality of life following the conclusion of treatment. Clinical trial information: NCT00456599.

Prognostic factors for achieving resection following neoadjuvant radiation therapy for borderline resectable pancreatic adenocarcinoma

285

Background: Margin-negative (R0) surgical resection is the only potentially curative therapy for pancreatic cancer. For patients deemed borderline resectable (BL), neoadjuvant chemoradiotherapy (NCRT) increases the likelihood of subsequent R0 resection and improves overall survival. Prognostic factors for achieving resection following NCRT have yet to be clearly identified. Methods: 50 consecutive patients diagnosed with BL pancreatic cancer by a multidisciplinary tumor board from 2008-12 were retrospectively identified. Pre- and post-NCRT CT scans and surgical specimens were centrally reviewed by a blinded radiologist and pathologist, respectively. Results: 29 patients underwent resection following NCRT, while 21 remained unresectable. Between the two groups, age, gender, mean RT dose, and proportion of pancreatic head tumors were not significantly different. Lack of the following factors was favorably associated with resection: SMV/PV encasement (p=0.01), SMA involvement (p=0.02), ascites (p=0.01), and questionable/overt metastases (p=0.01). Notably, celiac artery involvement/encasement, common hepatic artery encasement, and percentage change in tumor volume were not significant predictors of resectability (all p>0.05). Additionally, tumor volume and degree of individual vessel involvement did not significantly change from scans before and after NCRT (all p>0.05). Median OS was 22.9 vs.13.0 months in resected and unresected patients, respectively (p<0.001). Of resected patients, 93% had negative margins, 28% had positive nodes, 27% demonstrated <10% viable tumor, and 12% had pathologic complete response at surgery. Conclusions: Certain radiographic features appear more strongly associated with resectability after NCRT than others. Despite the fact that tumor-vessel interactions do not change significantly due to NCRT, subsequent R0 resection rates are high, nodal involvement is low, nearly 1/3 of patients have minimal residual tumor, and outcomes are improved. Further studies are needed to elucidate novel biomarkers or functional imaging predictors for successful resection following neoadjuvant therapy.

Phase II study of erlotinib combined with adjuvant chemoradiation and chemotherapy for resectable pancreatic cancer

269

Background: Amplification and overexpression of the EGFR gene and surface protein have been described in up to 80% of pancreatic tumors, making EGFR an attractive target in developing new adjuvant therapy for pancreatic adenocarcinoma (PDAC). Inhibition of EGFR has been suggested to provide additive activity when combined with capecitabine and radiation. Here we evaluate the antitumor activity and toxicity profile of erlotinib combined with adjuvant chemoradiotherapy (CRT) and chemotherapy. Methods: 50 patients with resected stage I/II PDAC were enrolled in a phase II trial of adjuvant erlotinib and capecitabine administered concurrently with IMRT (50.4 Gy), followed by 4 cycles of erlotinib and gemcitabine. Results: Median length of follow-up was 18.2 months (IQR, 13.8-27.1). Seventy-nine percent of tumors were of the pancreatic head, 85% had nodal involvement, and 17% had positive margins. Median RFS was 15.6 months (95% CI, 14.1-17.1), local RFS 21.1 months (95% CI, 17.1-25.1), and OS 24.4 months (95% CI, 17.1-31.6). Local recurrence was only observed in 19% patients and synchronous recurrence in 8%. Patients with maximum tumor diameter of ≤3 cm showed superior RFS (17.9 vs. 14.0 months; P=0.049), as did patients with cutaneous reaction to erlotinib (16.3 vs. 9.3 months, P=0.021). Superior OS was associated with less than median (32.3U/mL) pre-CRT CA19-9 values (28.2 vs. 19.0 months, P=0.012). During CRT, 31% patients experienced grade 3 toxicity and 2% grade 4, while 31% patients required a treatment break/stopped treatment early. During post-CRT chemotherapy, 35% patients experienced grade 3 toxicity and 8% grade 4, while 30% required a dose reduction. Conclusions: Results of this phase II trial suggest erlotinib combined with standard adjuvant CRT and chemotherapy provides excellent local disease control and reasonable tolerability compared with existing adjuvant regimens. Patients with maximum tumor diameter of ≤3 cm, cutaneous reaction to erlotinib, and less than median pre-CRT CA19-9 values appear to especially benefit from this new adjuvant regimen. Clinical trial information: NCT00962520.

Blood-based screening for methylation changes in colorectal cancer patients using novel nanotechnologies

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Background: Identification of blood-based biomarkers for cancer screening is essential in order to develop novel and minimally invasive methods for colorectal cancer screening. Our lab has successfully applied a novel nanotechnology that allows us to detect and amplify a single tumor DNA fragment in a plasma sample. This DNA is tested for methylation of several genes including TFPI2 which has shown to be highly sensitive and specific for the detection colorectal cancer in stool. Methods: Whole blood was obtained from 18 colorectal cancer patients and plasma was isolated. Plasma was processed using Methylation On Beads nanotechnology (MOB) and bisulfate treated. Methylation status was determined via quantitative PCR method. Results: Two genes, TFPI2 and IGFBP3, were detected with a high sensitivity. TFPI2, demonstrated a methylation frequency of 94.4%, which is concordant with the TFPI2 methylation frequency of 99% in primary colorectal cancer tissues. IGFBP3 showed the methylation frequency of 61.1%, which corresponds with the methylation frequency of 52% in retrospective colorectal cancer tissues in previous studies. Quantification using standard curves indicated a single copy level of DNA found in plasma. Conclusions: Blood-based screening is challenging due to extremely low quantities of circulating DNA in blood. Utilizing a novel nanotechnology that detects DNA at a single copy level, the methylation changes in colorectal cancer were successfully detected in plasmas at similar frequencies as in tissue samples. This study has demonstrated the feasablility and applicability to blood-based screening. Future studies will focus on improving the sensitivity and determining the specificity of this method.

Patient retention and costs associated with a pancreatic multidisciplinary clinic

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Background: Multidisciplinary clinics (MDC) are a burgeoning method of administering timely and comprehensive oncologic care. The continuity of care achievable with MDCs, in addition to their costs, are not well-described. We compared retention rates and charges for MDC patients to patients with individual referrals at the same academic center. Methods: The geographic origins of 482 MDC patients and 3,766 non-MDC patients, all referred for pancreatic cancer treatment between 2008-2010, were defined as “local,” “adjacent states,” and “non-adjacent states.” Proportions of patients in each group who presented initially and subsequently returned were compared using chi-squared tests. Multivariate adjustment was performed for disease stage and other clinical risk factors. Gross charges per patient were determined using billing data. Results: Overall, the MDC retained a higher percentage of patients for subsequent treatment than the non-MDC group (60.8% vs. 53.6%; p=0.003), as well as all three individual regions. Multivariate adjustment results are not yet available, but will be at the time of the meeting. Mean charges per patient were 11% higher for the non-MDC group. Conclusions: The MDC achieved higher patient retention, suggesting improved continuity of care. Total charges were higher for the non-MDC group, suggesting that MDCs may be more cost-effective. [Table: see text] [Table: see text]

Preliminary decision-tree analysis of costs to payors associated with a pancreatic multidisciplinary clinic

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Background: Multidisciplinary clinics (MDC) are well-established formats for delivering thorough oncologic evaluation and treatment. Although much evidence identifies an association between MDCs and superior clinical outcomes, their effect on total costs to payors is not well described. We performed a preliminary decision analysis of likely costs associated with a pancreatic MDC versus other settings, referring to known changes in diagnosis resulting from our pancreatic MDC (Pawlik, Ann Surg Oncol.2008; 15(8):2081-8). Methods: We extracted cost data from previous decision-analyses to determine expected cancer treatment costs for patients with resectable (Ljungman, World J Surg. 2011; 35:662-670), locally advanced (Murphy, Cancer. 2011;118:1119-1129), and metastatic disease (Attard. J Clin Oncol. 2012 [suppl 4; abstr 199]), using the most updated studies available. We then mapped these costs to a decision-analysis, modeling staging patterns that change after referral to the MDC. The expected cost of each disease stage was multiplied by its frequency of occurrence for both scenarios. A unique Markov analysis with consistent assumptions was not available at submission, but will be at the time of the meeting. Results: From the literature, an initial diagnosis of resectable disease was associated with the highest cost, and metastatic disease with the lowest. The percentage of patients managed for each disease stage in both clinic settings are indicated in the table. Because the MDC scenario resulted in a lower frequency of resectable and a higher frequency of metastatic staging at initial diagnosis, costs were 4.7% lower in the MDC scenario. Conclusions: In this preliminary analysis, the MDC showed potential to achieve up to 4.7% in cost-savings over treatment in conventional clinic settings, suggesting that the MDC setting for pancreatic cancer may be cost-saving to payors. [Table: see text]

A randomized phase III multi-institutional study of TNFerade biologic with 5-FU and radiotherapy for locally advanced pancreatic cancer: Final results

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Background: TNFerade biologic (TNF) is a novel means of selective delivery of TNF-α to tumor cells by gene transfer through intratumoral (IT) injection. TNF is a replication deficient adenovirus vector containing TNF-α cDNA ligated downstream from a radiation-inducible Egr-1 promoter, allowing spatiotemporal constraint of TNF-α production to the radiation field. Herein we report the final results of a multi-center, randomized, open-label, controlled phase III trial of TNF with chemoradiotherapy for locally advanced pancreatic ductal adenocarcinoma (PDA). Methods: Pts with locally advanced PDA were randomized 1:2 to standard of care (SOC; 5-FU/RT followed by GEM) versus TNF + SOC. RT dose was 50.4 Gy in 28 fractions. Concurrent 5-FU (200 mg/m2/day IV) started on day 1 of RT each wk. TNF was injected IT ~4 hrs prior to RT weekly by percutaneous (PTA) or endoscopic (EUS) approach. 4 wks after RT, GEM (1000 mg/m2 IV) was given until progression or toxicity. Results: Of 277 pts, 187 were randomized to TNF and 90 to SOC. Demographic/baseline characteristics were similar between arms (all NS), as was GEM received (67 vs. 68%; 7.0 vs. 7.6 total wks). Median f/up was 9.1 mos (range, 0.1-50.5). Median OS for TNF by ITT analysis was 10.1 mos (95% CI, 9.1-11.7) vs. 10.0 mos (95% CI, 7.6-11.2) for SOC (p=0.6). TNF delivery method did not affect OS (9.4 mos for PTA vs. 11.5 for EUS; p=0.7). Baseline CA19-9 > 1000 was found to impart independent risk to TNF pts (HR=1.7; p=0.02). Subgroup analysis (SGA) of 86 pts with T1-T3 disease showed an OS benefit for TNF compared to SOC (10.9 vs. 9.0 mos, respectively; p=0.04). TNF resulted in more grade 1-2 fever/chills (p<0.001) as well as grade 3 (p<0.001) and 4 (p=0.05) toxicities (commonly lymphopenia, hypo/hyperkalemia, abd/chest pain) than SOC. Use of PTA vs. EUS did not affect grade 3/4 toxicity rates. Conclusions: TNF + SOC did not prolong OS for locally advanced PDA. SGA reveals a possible OS benefit for early stage (T1-T3) tumors and CA19-9 < 1000. PTA and EUS injection achieved similar rates of efficacy and toxicity. Grade 1-2 toxicity typical of systemic exposure to TNF-α (pyrexia/hypotension/chills) was common, but grade 3-4 was minimal.

A phase II multi-institutional study to evaluate gemcitabine and fractionated stereotactic body radiotherapy for unresectable, locally advanced pancreatic adenocarcinoma

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Background: Phase I/II studies with single-fraction (25 Gy) stereotactic body radiotherapy (SBRT) for pancreatic ductal adenocarcinoma (PDA) have shown local progression free survival (LPFS) rates of >90%, but are limited by late GI toxicity and minimal tumor response. We performed a phase II multi-center trial of gemcitabine (GEM) and fractionated SBRT to determine if a high rate of LPFS with reduced toxicity could be achieved. Methods: After multidisciplinary review, 32 pts with locally advanced PDA received GEM in sequence with SBRT (6.6 Gy in 5 consecutive daily fractions, 33 Gy total). LPFS, metastasis free survival (MFS), and overall survival (OS) were measured from date of tissue diagnosis. Objective tumor response (OTR) was assessed by RECIST/PERCIST. EORTC QLQ-C30/PAN26 questionnaires were used to measure QOL. Results: Median f-up was 12 mos (range, 2-23). Mean age was 69.9 yrs (SD, 9.8) and 62% were male. Pts received a mean of 2.2 (SD, 1.0) GEM doses prior to SBRT and 8.3 (SD, 5.6) doses total. All pts completed SBRT. Median OS was 15.9 months (95% CI, 12.7-18.8). Stratification by CA19-9 > or < 90 at diagnosis yielded a hazard ratio of 6.2 for > 90 (p=0.021). Median LPFS has not been reached and median MFS was 10.2 mos (95% CI, 2.9-17.5). LPFS rate at 1 year was 87%. OTR on CT was seen in 41%, while 41% had stable disease and 18% progressed. Tumor metabolic activity decreased in 17/18 patients with pre/post-SBRT PET available. Mean peak SUV was 4.0 pre-SBRT versus 2.4 post-SBRT (p=0.002). Median CA19-9 was reduced from 124.7 prior to SBRT to 43.9 afterwards. Acute toxicity included: grade 2 anorexia (37%), fatigue (28%), nausea (22%), abd pain (19%), weight loss (9%), diarrhea (3%); gr 3 nausea (9%); and gr 4 nausea (6%). Late gr ≥3 GI toxicity was seen in 9%. Mean QOL score 4 wks post-SBRT was similar to baseline (p=0.38). At 6 mos there was a trend towards improved QOL (p=0.07). Conclusions: Fractionated SBRT with GEM achieves high rates of LPFS and tumor response. Minimal grade ≥3 acute and late toxicity was observed. SBRT is more likely to benefit patients with Ca-19-9 <90. A combination of SBRT with more aggressive chemotherapy may further improve outcomes.

Treating patients with colorectal liver metastasis: A national decision-making analysis to understand choice of therapy

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Background: Criteria for resectability of colon cancer liver metastases (CLM) are evolving, yet little is known about how physicians choose a therapeutic strategy for potentially resectable CLM. Methods: Physicians completed a national web-based survey that consisted of varied CLM case scenarios. Respondents choose among 3 treatment strategies: immediate liver resection(LR), preoperative chemotherapy followed by surgery(C→LR), or palliative chemotherapy (PC). Data were analyzed using multinomial logistic regression, yielding relative risk ratios (RRR). Results: Of 219 respondents, 79% practiced at academic centers and 63% were in practice ≥10 years. Median number of cases evaluated was 4/month. Surgical training varied: 51% surgical oncology (SO), 44% hepatobiliary/transplant (HB/LT), 5% no fellowship. While each factor impacted choice of CLM therapy, the relative impact differed (p<0.01). Synchronous CLM presentation increased the choice of C→LR (OR 4.27) and PC (OR 3.10) versus LR (p<0.001). For patients with more extensive intrahepatic disease (i.e., 5 tumors, both lobes) respondents strongly favored C→LR (OR 5.12) and PC (OR 9.60) versus LR (p<0.001). The presence of hilar lymph-node disease was associated with a strong aversion to LR with surgeons more likely to choose C→LR (OR 8.92) or PC (OR 49.9) (p<0.001). Interestingly, even the presence of a resectable solitary lung metastasis strongly deterred choice of LR with respondents favoring C→LR (OR 4.43) or PC (OR 6.97) (p<0.001). While other factors such as patient age, tumor size, and extent of resection impacted choice of therapy, the relative size of these effects was modest. After controlling for clinical factors, surgeons with more years in practice were more likely to choose LR (RRR 1.4). SO-trained surgeons were more likely than HB/LT-trained surgeons to choose C→LR (RRR 2.5) or PC (RRR 4.15)(p<0.001). Conclusions: This is the first study to define the relative impact of key clinical factors on choice of therapy for CLM. While clinical factors influence choice of therapy, surgical subspeciality and physician experience are also important determinants of care.

Effect of chemoradiation-related lymphopenia on survival in patients with unresectable, locally advanced pancreatic adenocarcinoma

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Background: Pancreatic ductal adenocarcinoma (PDA) has been shown to elicit antitumor cell-mediated immune responses. In high grade gliomas, treatment-related lymphopenia has been associated with shorter survival. This study was performed to determine if patients with locally advanced PDA treated with definitive chemoradiation therapy (CRT) develop significant lymphopenia and if this affects overall survival (OS).

Methods: A retrospective analysis of patients with locally advanced PDA treated at a single institution with CRT from 1997-2009 was performed. Serial lymphocyte counts were recorded and OS was analyzed as a function of lymphopenia and known prognostic factors.

Results: 99 patients met eligibility criteria (≥18 years of age, ECOG performance status 0-2, and had baseline/follow-up lab values measured at our institution). Mean age was 61.6 years (SD, 11.6), 55% were male, mean tumor size 4.1 cm (SD, 1.6), and 97 had stage III disease. Median pre/post-CRT CA19-9 values were 241.5 and 105.2 U/mL, respectively. Total lymphocyte counts were normal in 87% of patients prior to RT. Mean RT dose was 47.3 Gy (SD, 8.2) and concurrent chemotherapy was 5-FU (67%), gemcitabine (20%), taxotere (7%), or none (6%). Chemotherapy dose reduction was necessary in 9%, and 39% required a RT break. Total lymphocyte counts fell to ≤500 cells/mm3 in 51% two months after initiating CRT with a median reduction of 66% from baseline (p<0.0001). Median OS of patients with lymphocyte counts ≤500 cells/mm3 at 2 months was 7.7 months (95% CI, 6.8-8.7) versus 15.4 (95% CI, 11.9-19.0) for patients with >500 cells/mm3 (p<0.001). Univariate analysis additionally revealed that among pre-treatment patient characteristics, only age ≥65 was significantly associated with OS (8.8 vs. 11.4 months; p=0.043). Type of concurrent chemotherapy was not significantly associated with OS. Multivariate analysis revealed a significant association between survival and lymphocyte count (<500 vs. ≥500 cells/mm3) at 2 months post-CRT (HR 3.8, p<0.001).

Conclusions: Definitive CRT induced lymphopenia is frequent, severe, and appears to be an independent predictor for OS in patients with locally advanced PDA.

Radiation in the management of pancreatic neuroendocrine tumors

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Background: Radiation therapy (RT) has not historically been incorporated into multidisciplinary management of pancreatic neuroendocrine tumors (PNTs). We provide a two-institution series of patients with PNTs who were treated with external beam RT either neoadjuvantly to attempt down-staging for surgery, or in the setting of post-surgical recurrence. Our objective was to assess treatment response and outcomes in this cohort of patients.

Methods: We identified eleven patients with a pathologic diagnosis of PNT from 2006-2011 who received external beam RT to the primary tumor or resection bed. Each institution’s electronic medical record was used to evaluate patient demographics, disease characteristics, treatment regimens and tolerance, radiographic response, and survival.

Results: Our series consists of eleven patients (6 men, 5 women) with a mean age of 57 years (range 37-72 years). All had biopsy proven PNT and were clinically T3 (n=3) or T4 (n=8), M0. Five patients were clinically node positive. All patients received RT to the primary tumor or resection bed to a median dose of 50.4 Gy. Seven patients received concurrent chemotherapy with capecitabine at a median dose of 1000mg/m2 bid. Nine patients were treated definitively for locally advanced disease, two of whom subsequently underwent surgical resection. Two patients were treated to palliate post-resection recurrence. Initial radiographic response to RT included 2 complete responses (CR), 2 partial responses (PR), 4 stable disease, 3 progressive disease (PD). Two patients were classified as PD due to the development of distant metastases less than 2 months after completing RT. Two grade 3 toxicities were documented (one early, one late). At a median follow-up of 30.4 months, three patients had died with evidence of PD, two had died without evidence of PD, three were alive with metastases, and three were alive without evidence of disease progression (1 stable, 1 PR, 1 CR). From the start of RT, median overall survival was 32.1 months; progression free survival was 14.6 months.

Conclusions: RT may have the potential to convert PNTs from locally-advanced to resectable. RT may also increase local control of PNTs. Consideration should be given to the use of RT in prospective trials of PNT treatment.