Pockaj, Barbara A.

131 Background: Research demonstrating a volume-outcome relationship has resulted in regionalization of complex cancer surgery to high volume hospitals. A simultaneous national trend towards improved surgical outcomes brings into question whether the potential benefits of regionalization are still relevant. We hypothesize that the difference in adjusted post-operative mortality between low and high volume hospitals has decreased over time. Methods: The National Cancer Database (NCDB) was used to identify patients with colon, esophageal, and pancreatic cancer undergoing curative intent surgery from 2003-2011. Hospitals were divided into low ( < 25th percentile), medium (25th-75th) and high ( > 75thpercentile) volume groups depending on annual volume of cancer-specific surgery. Year-specific hospital averaged observed/expected (O/E) ratios were calculated for 90-day mortality. Poisson regression was used to model hospital averaged O/E ratios over time. Results: Our study population included 343,929 patients with colon (88%), esophageal (5%) and pancreatic (7%) cancer. There were significant (p < 0.05) improvements in adjusted 90-day mortality from 2003 and 2011 for all volume categories and cancer types, except in high volume hospitals for esophageal cancer. In 2003, high volume hospitals had significantly better outcomes compared to low volume hospitals for all cancer types, as suggested by lower O/E ratios for 90 day mortality (p < 0.05). However, by 2011 the difference in O/E ratios for 90 day mortality was no longer significantly lower for high compared to low volume hospitals (p > 0.05); this was true for all three cancer types (Figure1). Conclusions: During the period of our study, 90-day mortality following gastrointestinal cancer surgery improved in low, medium and high volume hospitals. However, by 2011 the difference in adjusted post-operative mortality between low and high volume hospitals was not significantly different, likely due to global improvements in operative and peri-operative care. This attenuation of the volume-outcome curve has important implications for policy pertaining to regionalization of cancer care in the US.

Background: Patients diagnosed with melanoma of the foot have been reported to have a poor prognosis. We reviewed our experience at a tertiary-care medical clinic to determine the disease course in patients diagnosed with melanoma of the foot. Methods: A retrospective review was performed of 38 patients with a diagnosis of primary or locally recurrent melanoma of the foot treated between January, 1988, and July, 2004. The main outcome measures included methods of diagnosis, clinical and histopathologic features, and patterns of recurrence. Results: The mean age at diagnosis was 61 years; most were women (58%) and Caucasian (95%). The average time to diagnosis was 17 months. Initial clinical diagnosis had been considered benign in 12 (32%). The median Breslow thickness was 1.75 mm, T1 lesions were the most common, and acral lentiginous melanoma accounted for 42%. Thirteen patients (34%) had ulcerated lesions. Sentinel lymph node biopsy specimens of 25 patients identified four (16%) with metastatic disease. Surgical complications occurred in 12 patients, usually after skin graft or soft-tissue flap reconstruction. Systemic recurrence developed in six patients, four of whom also had regional recurrence. Conclusions: Most patients were elderly Caucasian women and most presented with early-stage disease, but diagnosis can be difficult and a subgroup presented with thick melanomas. Reconstructive surgical procedures had a high rate of complications; however, overall functional outcomes were good. Stage of cancer at diagnosis was associated with systemic metastases.

94 Background: Octogenarian breast cancer (BrCa) patients accept less aggressive BrCa treatment due to decreased life expectancy, increased comorbidities, and high likelihood of death from other causes. Unfortunately little data exist stratifying octogenarian outcomes by disease risk. We sought to characterize treatment and recurrence patterns in patients >80yo. Methods: Retrospective review identified 432 women >80yo treated surgically for stage 0-3 BrCa between 11/99-8/11. We gathered clinicopathologic data and classified patients by disease risk as DCIS only, low risk (<2cm and ER positive and node negative), or high risk (>2cm or ER negative or node positive). We compared recurrence rates and estimated survival by Kaplan-Meier curves. Results: Among the 432 women, disease was found by mammogram in 86%, treated with BCT in 64%, and predominantly ER-positive (87%). We classified patients as having DCIS only (N=61), low risk (N=205), or high risk (N=166) disease. We identified the following deviations from standard treatment guidelines: 68% DCIS BCT and 38% high risk BCT patients did not have radiation therapy, 25% low risk BCT patients had surgery only, 51% low risk patients did not take adjuvant hormonal therapy, and 40% high risk patients had no adjuvant chemo/hormonal therapy. At 5 and 10 years the overall estimated survival was 63% and 31%, respectively. Overall, 19/432 (5%) patients developed recurrence (table 1). Patients needing mastectomy for high risk disease had significantly higher risk of recurrence than high or low risk BCT patients (p=0.02). Of the 19 recurrence patients, 7/19 (37%; 1 DCIS, 1 low risk, 5 high risk) occurred despite standard multimodality treatment, while12 (63%; 3 low risk, 9 high risk) had the initial tumor treated less aggressively due to patient choice (n=9) or medical co-morbidities (n=3). Conclusions: Significant deviations from treatment guidelines occur in women >80yo. Those with high risk disease should be counseled accordingly and encouraged to receive adjuvant treatment as two thirds of women >80yo will live at least 5 years. [Table: see text]

6 Background: Traditional screening mammography (MG) enables early detection of breast cancer and therefore results in decreased mortality. Mammography, however, is an imperfect tool and limited by an overall sensitivity of 75-85%. Specificity is limited as well resulting in many false-positive examinations and unnecessary follow-up examinations. The recent development of contrast-enhanced digital mammography (CEDM) has made the usage of IV contrast enhancement with mammography a possibility. CEDM is an angiographic technique that uses digital subtraction, which removes the normal mammary gland on images in order to detect breast tumors and visualize their vascularity. The literature is promising with regard to CEDM as studies have found that CEDM achieves increased sensitivity without reductions in specificity in comparison to MG, US and/or MRI. Methods: In this multi-reader study we compared the diagnostic accuracy of CEDM as an adjunct to MG/US in patients with suspicious findings (BI-RADS 4). The study population included 31 patients who were imaged with CEDM prior to their scheduled US or stereotactic-guided biopsy. We compared the relative performance of MG/US alone versus MG/US/CEDM in determining the probability of malignancy. Histology served as the gold standard. Results: See table below. Conclusions: The addition of CEDM to the workup of suspected lesions on MG and/or US preliminarily decreases the number of false-positive MG thereby with potential to reduce cost and unnecessary patient harm. [Table: see text]

13 Background: A Memorial Sloan Kettering Cancer Center (MSKCC) nomogram predicts disease−specific survival (DSS) following R0 resection for gastric adenocarcinoma using patient and tumor factors, with predictive ability superior to that of the current AJCC staging system. However, validation has only been performed in high−volume, specialized institutions. The goal of this study is to compare nomogram-predicted survival with actual survival by using a population database with the largest sample size reported to date. Methods: A retrospective review of all gastric cancer patients from Surveillance, Epidemiology and End Results (SEER) registry data from 1988 to 2000 was conducted. Data for patient age, tumor size, gender, primary location of tumor, Lauren histology, depth of tumor invasion, and % (+) and (-) lymph nodes was entered into the nomogram calculator for each patient. Nomogram-derived 5−year DSS was compared with actual DSS survival using Cox proportional hazards regression and Kaplan-Meier estimates. Results: 4,700 patients were identified. Mean patient age was 68.7 years (SD 12.3), and mean tumor size was 4.8 cm (SD 2.7). The commonest tumor location was the body/middle third of stomach (1519, 32%), followed by the gastro−esophageal junction (1381, 29%) and the antrum (1376, 29%). The majority of patients (76%) had intestinal histology. The estimated proportion of patients surviving 5 years was 23%, 48%, 58%, and 82% for survival groups defined by nomogram likelihoods of 5−year DSS of 0−25%, 26−50%, 51−75%, and 76−100%, respectively. Relative to patients in the 76−100% 5−year nomogram group, patients in the 0−25%, 26−50%, and 51−75% group had significantly higher likelihood of death with hazard ratios of 7.0 (95% CI 6.1−8.0), 3.3 (95% CI 2.8−4.0), and 2.6 (95% CI 2.2−3.0), respectively (all p<0.001). Median follow-up was 9.1 years (range, 0−18). The concordance index (c−index) for the 5−year nomogram score was 0.68 (95% CI 0.67−0.69). Conclusions: There is good discrimination of survival between nomogram-predicted survival groups. Our results validate the use of the MSKCC nomogram in the setting of the general population, outside of specialized institutions, for predicting DSS following resection of gastric adenocarcinoma.

96 Background: In the last decade there has been an increase in the incidence of contralateral prophylactic mastectomy (CPM) for unilateral breast cancer. Although many factors have been proposed to explain this trend, the impact of breast reconstruction on the decision to undergo CPM has not been extensively studied. Methods: A retrospective review of breast cancer patients from Surveillance, Epidemiology and End Results (SEER) registry data (2004-2008) was conducted. Characteristics of patients undergoing CPM were evaluated. Results: 71,176 patients with a diagnosis of stage I-III infiltrating ductal or lobular breast cancer underwent mastectomy for their primary lesion. Among these, 10,558 patients (15%) underwent a CPM. A significantly higher proportion of women undergoing CPM had reconstruction performed (44%) than those patients not undergoing CPM (13%), p<0.001. On multivariate analysis (Table), significant variables predicting CPM included age <50 years (OR 10.12), breast reconstruction (OR 3.58), and lobular histology (OR 1.41), all p<0.001. Of the 12,466 patients (18%) who underwent reconstruction, 4,636 (37%) had implant reconstruction, 4,498 (36%) had tissue reconstruction, and 1,122 (9%) had combined tissue/implant reconstruction (no data for 18%). On multivariate analysis, predictors of reconstruction included age <50 years (OR 20.5; CI 18.5-22.7), year of surgery (2008 vs. 2004; OR 1.60; CI 1.49-1.71), low tumor grade (OR 1.19; CI 1.13-1.25) and ER+ status (OR 1.16; 95% CI 1.10-1.23). The use of radiation therapy was associated with a lower likelihood of pursuing reconstruction (OR 0.61; CI 0.58-0.65). Conclusions: Apart from age, the factor most strongly associated with CPM is the decision to have reconstructive surgery performed. This suggests that CPM may not be purely associated with risk-reduction but also with treatment factors such as cosmesis. [Table: see text]

AbstractTo examine, in a prospective fashion, the utilization and efficacy of adjuvant radiation therapy (RT) in patients with resected desmoplastic melanoma (DM). Adult patients with resected, margin‐negative, and nonmetastatic DM were eligible for this single‐arm prospective phase II study. Patients were to receive postoperative RT, 30 Gy in five fractions, to the operative bed with 2‐ to 3‐cm margins (depending on the tumor location). Nodal basin RT was not allowed. The primary study endpoint was the 2‐year local recurrence rate (LRR). Secondary endpoints included the incidence of regional and distant metastatic disease, progression‐free survival, overall survival (OS), and treatment‐related toxicity. Twenty patients with a single de novo DM lesion meeting trial eligibility criteria were enrolled and treated. The 2‐year LRR was 10%, with two patients demonstrating a LR within 2 years of completion of protocol therapy. No regional or distant failures occurred. OS at 2 and 5 years was 95 and 77%, respectively. There were no grade 3 or higher acute or late adverse events that were related to the protocol therapy. Adjuvant RT after wide local excision (WLE) for DM is efficacious and well tolerated. It should be considered for DM patients after margin‐negative WLE. Additional study is needed to further refine low‐risk patient populations that can potentially have adjuvant RT omitted as part of the treatment plan.

Cancer vaccines have often failed to live up to their promise, although recent results with checkpoint inhibitors are reviving hopes that they will soon fulfill their promise. Although mutation-specific vaccines are under development, there is still high interest in an off-the-shelf vaccine to a ubiquitous antigen, such as MUC1, which is aberrantly expressed on most solid and many hematological tumors, including more than 90% of breast carcinomas. Clinical trials for MUC1 have shown variable success, likely because of immunological tolerance to a self-antigen and to poor immunogenicity of tandem repeat peptides. We hypothesized that MUC1 peptides could be optimized, relying on heteroclitic optimizations of potential anchor amino acids with and without tumor-specific glycosylation of the peptides. We have identified novel MUC1 class I peptides that bind to HLA-A*0201 molecules with significantly higher affinity and function than the native MUC1 peptides. These peptides elicited CTLs from normal donors, as well as breast cancer patients, which were highly effective in killing MUC1-expressing MCF-7 breast cancer cells. Each peptide elicited lytic responses in greater than 6/8 of normal individuals and 3/3 breast cancer patients. The CTLs generated against the glycosylated-anchor modified peptides cross reacted with the native MUC1 peptide, STAPPVHNV, suggesting these analog peptides may offer substantial improvement in the design of epitope-based vaccines.