Citations

147 Background: Lymphopenia during radiation therapy (RT) has been associated with worse oncologic outcomes in a number of malignancies, including esophageal cancer (EC). No studies to date have investigated specific dosimetric parameters associated with this lymphopenia in EC. We performed an analysis of RT dose to multiple organs at risk (OARs) to investigate associations with grade 4 lymphopenia (G4L). Methods: Consecutive EC patients receiving curative intent chemoradiotherapy +/- surgery between July of 2015 and December of 2017 were included. Lymphocyte nadir was defined as the lowest lymphocyte count during RT. G4L was defined as absolute lymphocyte count <200/mm3. Dose to OARs including aorta, body, bone marrow, heart, liver, lung, and spleen were calculated. Univariate logistic regression analyses were performed for each OAR at the 1, 5, 10, 15, 20, 30, 35, 40, and 50 Gy levels with volume receiving dose ‘x’(VxGy) analyzed as a continuous variable per 10% increase. Clinical tumor volume (CTV) and RT modality (photon vs. proton) as well clinical factors including sex, stage (I/II vs. III/IV), age (per 10 year increase), and BMI (per 5 unit increase) were also analyzed. Results: One hundred forty-four pts were identified for inclusion. Seventy-nine pts received photon RT and 65 proton RT. Chemotherapy was weekly carbotaxol (99%). G4L at nadir was 40% overall (56% photon, 22% proton). By organ, body V1-V30Gy (OR 1.45-8.18, p<0.01), heart V1-V30Gy (OR 1.24-1.49, p<0.01), liver V1-V35Gy (OR 1.23-2.75, p<0.01), lung V1-V30Gy (OR 1.26-5.73 p<0.01), and spleen V1-V40Gy (OR 1.26-1.49 p<0.01) were highly associated with G4L whereas dose to aorta and bone marrow were not. Advanced stage (OR, 3.92 p<0.01), photon vs. proton (OR 4.58 p<0.01), and CTV (per 100 cc’s (OR=1.21, p<0.01)) were also associated with G4L. Sex, age, and BMI were not associated with G4L. Conclusions: Low to intermediate dose volumes to OARs including body, spleen, liver, lungs, and heart were associated with G4L. These findings provide rational for the differences seen in rates of G4L for photon versus proton RT.

131 Background: Trimodality therapy is the standard of care for patients with resectable cancer of the esophagus. However, patients ≥75 years have been underrepresented or excluded from landmark clinical trials to date. We investigated the feasibility and safety of treatment of esophageal cancer with trimodality therapy in patients’ ≥ 75 years. Methods: We performed a retrospective review of all patients ≥75 years who received trimodality therapy for esophageal cancer in 3 high volume tertiary cancer institutions from June 2007 to June 2013. All patients received neoadjuvant radiation with concomitant chemotherapy followed by esophagectomy. Toxicities and clinical outcomes were abstracted from the electronic medical record and partially from a prospectively maintained database. Overall and disease-free survival were estimated using the Kaplan-Meier method. Results: Five hundred seventy patients were treated with trimodality therapy for esophageal cancer from 2007-2013. Of these, 38 patients (7%) were 75 or older at the time of diagnosis. At diagnosis, comorbidities included coronary artery disease (32%), atrial fibrillation (11%) and COPD (13%). The majority of patients (87%) received 50.4Gy/28 fractions. 5-fluorouracil (5-FU)/cisplatin was the most common chemotherapy regimen (37%), followed by 5-FU/docetaxel (24%). A total of 13 patients (34%) developed acute grade ≥3 toxicity associated with neoadjuvant therapy. The most common acute grade 3 toxicities were haematological (10%), nausea (8%), esophagitis (5%) and fatigue (5%). Significant postoperative complications included respiratory (empyema, ARDS, pleural effusion) (39%), arrhythmia (32%), anastomotic leak (5%), and ileus (5%). There were 2 deaths (5%) within 90 days of surgery: one was secondary to empyema, the other developed DIC and sepsis. Median overall survival and disease free survival were 4.4 and 2.3 years respectively. Conclusions: Trimodality treatment is a reasonable approach for management of carefully selected elderly patients with esophageal cancer, with similar rates of cancer outcomes, and treatment related morbidity and mortality as compared to younger patients.

121 Background: We evaluated the role of pre-treatment pulmonary function testing (PFT) in predicting the likelihood of cardiac and/or pulmonary toxicity for esophagus cancer patients receiving trimodality therapy. Methods: From 2007 to 2013, 64 patients with esophageal cancer received trimodality therapy at a single tertiary center with pre-treatment PFTs. The odds ratio of pre-treatment PFT as a predictor of cardiopulmonary toxicity was assess with univariate analysis (UVA). FEV1 (forced expiratory volume in 1 second) and DLCO (diffusion capacity for carbon monoxide) were assessed per 0.5-unit decrease. Percent FEV1 and DLCO predicted were assessed per 10% decrease. Results: The median age was 62 years (range, 41-79) with 88% male patients. A total of 70% of patients had adenocarcinoma with 66% having stage 3 disease. Most patients were former (43%) or current smokers (32%) and 18% had COPD. One or more cardiac comorbidities were observed in 54% of patients. The median RT dose was 50 Gy and the most frequent concurrent chemotherapy was cisplatin/5FU (53%). The median pre-treatment FEV1 and DLCO was 2.8 liters (range, 1-4.9) and 22.5 mL/min/mmHg (range, 17.2-25.5), respectively. This correlated to a median percent predicted value for FEV1 and DLCO of 85% (range, 30-124%) and 81.5% (range, 49-119%), respectively. The overall rate of any cardiac and pulmonary toxicity was 35% and 50%, respectively. Percent predicted value of both FEV1 and DLCO was statistically associated with pulmonary but not cardiac toxicity (Table). Conclusions: Patients with compromised pre-treatment pulmonary function are at higher risk of developing post-treatment pulmonary toxicities. Pulmonary function testing should be routinely performed prior to initiation of trimodality therapy for patient risk stratification. [Table: see text]

Perioperative radiation therapy (RT) has been associated with reduced local recurrence in patients with retroperitoneal sarcomas (RPS); however, selection criteria remain unclear. We hypothesized that perioperative RT would improve survival in patients with RPS and would be associated with pathological factors. The National Cancer Database (NCDB) from 2004 to 2012 was reviewed for patients with nonmetastatic RPS undergoing curative intent resection. Tumor size was dichotomized at 15 cm based on 8th edition American Joint Committee on Cancer (AJCC) staging. Patients with the highest comorbidity score were excluded. Unadjusted Kaplan–Meier and adjusted Cox proportional hazards modeling analyzed overall survival (OS). Multivariable logistic regression modeled margin positivity. A total of 2,264 patients were included; 727 patients (32.1%) had perioperative radiation in whom 203 (9.0%) had radiation preoperatively. Median (IQR) RPS size was 17.5 [11.0–27.0] cm. Histopathology was high grade in 1048 patients (43.7%). Multivariable analysis revealed that perioperative radiation was independently associated with decreased mortality (HR 0.72, 95% confidence intervals (CIs) 0.62–0.84,p<0.001), and preoperative RT was associated with reduced margin positivity (HR 0.72, 95% CI 0.53–0.97,p=0.032). Stratified survival analysis showed that radiation was associated with prolonged median OS for RPS that were high-grade (64.3 vs. 43.6 months,p<0.001), less than 15 cm (104.1 vs. 84.2 months,p=0.007), and leiomyosarcomatous (104.8 vs. 61.8 months,p<0.001). Perioperative radiation is independently associated with decreased mortality in patients with high-grade, less than 15 cm, and leiomyosarcomatous tumors. Preoperative radiation is independently associated with margin-negative resection. These data support the selective use of perioperative radiation in the multidisciplinary management of RPS.

Objective: To determine the impact of histology on pathologic response, survival outcomes, and recurrence patterns in patients with esophageal cancer (EC) who received neoadjuvant chemoradiotherapy (CRT). Summary of Background Data: There is a paucity of data regarding comparative outcomes after neoadjuvant CRT between esophageal squamous cell carcinoma (SCC) and adenocarcinoma. Methods: Between 2002 and 2015, 895 EC patients who underwent neoadjuvant CRT followed by esophagectomy at 3 academic institutions were retrospectively reviewed, including 207 patients with SCC (23.1%) and 688 patients with adenocarcinoma (76.9%). Pathologic response, survival, recurrence pattern, and potential prognostic factors were compared. Results: Pathologic complete response (pCR) rate was significantly higher for SCC compared with adenocarcinoma (44.9% vs 25.9%, P < 0.001). After a median follow-up of 52.9 months, 71 patients (34.3%) with SCC versus 297 patients (43.2%) with adenocarcinoma had recurrent disease (P = 0.023). For patients who achieved a pCR, no significant differences were found in recurrence pattern, sites, or survival end-points between the 2 histology groups. For non-pCR patients, the SCC group demonstrated significantly higher regional and supraclavicular recurrence rates but a lower hematogenous metastasis rate than adenocarcinoma patients, whereas the adenocarcinoma patients had a more favorable locoregional failure-free survival (P = 0.005) and worse distant metastasis-free survival (P = 0.024). No differences were found in overall survival (P = 0.772) or recurrence-free survival (P = 0.696) between groups. Conclusions: SCC was associated with a significantly higher pCR rate than adenocarcinoma. Recurrence pattern and survival outcomes were significantly different between the 2 histology subtypes in non-pCR patients.

Objective: To discern recurrence risk stratification and investigate its influence on postoperative surveillance in patients with esophageal adenocarcinoma (EAC) after neoadjuvant chemoradiotherapy (CRT). Background: Reports documenting recurrence risk stratification in EAC after neoadjuvant CRT are scarce. Methods: Between 1998 and 2014, 601 patients with EAC who underwent neoadjuvant CRT followed by esophagectomy were included for analysis. The pattern, site, timing, and frequency of the first recurrence and potential prognostic factors for developing recurrences were analyzed. This cohort was used as the training set to propose a recurrence risk stratification system, and the stratification was further validated in another cohort of 172 patients. Results: A total of 150 patients (25.0%) achieved pathologic complete response (pCR) after neoadjuvant CRT and the rest were defined as the non-pCR group (n = 451) in the training cohort. After a median follow-up of 63.6 months, the pCR group demonstrated a significantly lower locoregional (4.7% vs 19.1%) and distant recurrence rate (22.0% vs.44.6%) than the non-pCR group (P < 0.001). Based on independent prognostic factors, patients were stratified into 4 recurrence risk categories: pCR with clinical stage I/II, pCR with clinical stage III, non-pCR with pN0, and non-pCR with pN+, with corresponding 5-year recurrence-free survival rates of 88.7%, 65.8%, 55.3%, and 33.0%, respectively (P < 0.001). The risk stratification was reproducible in the validation cohort. Conclusions: We proposed a recurrence risk stratification system for EAC patients based on pathologic response and pretreatment clinical stage. Risk-based postoperative surveillance strategies could be developed for different risk categories.