Ross, Helen J.

e20029 Background: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a pulmonary disorder with neuroendocrine cell proliferation with potential progression to lung neuroendocrine tumor (Lu-NET). Optimal diagnostic and treatment strategies have yet to be well defined. Herein, we aim to describe the Mayo Clinic experience with DIPNECH. Methods: A retrospective analysis was performed of patients diagnosed with DIPNECH within Mayo Clinic between January 2000-Febuary 2019. Cases were identified from clinical databases at Mayo Clinic. Data on demographics, disease characteristics, time of diagnosis, surgery, and last follow up date were extracted. Extent of symptom burden, treatment approaches, disease progression, and disease-free survival (DFS) were evaluated by chart review. Results: A total of 59 patients were identified with a median age of 63(43-81) years. The cohort was predominantly female (93.2%) and non-smoking (76.3%). Most patients (86.4%) had symptomatic disease with chronic cough being the most common (71.2%) followed by exertional dyspnea (44.1%). Imaging typically showed bilateral lung nodules (93.2%) with mosaic attenuation noted 69.5% of the time. Surgical resection was frequently completed to confirm diagnosis (94.9%). Most patients received inhaled glucocorticoids combined with a beta agonist (79.7%). Oral steroid use was seen in 49.2% of patients whereas a somatostatin analog was used in 15.3% following the diagnosis of DIPNECH. These medical interventions led to symptom relief in 23.7% of the patients. The median follow up for all patients was 19.5 months. Progression of tumorlets was seen in 48.7% of patients with only 7(17.9%) patients progressing to a diagnosis of Lu-NET. The 3-year DFS was 90.5%. Conclusions: This is amongst the largest studies completed evaluating DIPNECH patients. DIPNECH remains a rare disease more commonly diagnosed in women in their early 60’s. DIPNECH appears to have an indolent course with obstructive symptoms being the most common finding. A minority of patients experienced symptom relief with therapy. Overall, DIPNECH appears to have a low risk of progressing to Lu-NET based on the observation of this study.

7545 Background: Interpretation of lung cancer clinical trials is complicated by the heterogeneity of the patient population due to disease burden and comorbidities making pre-trial assessment of OS probability challenging. Methods: To create and validate a scoring system to estimate OS and improve the quality of future trials, this study evaluated the pretreatment prognostic factors of 2,442 pts with NSCLC. Univariate (UV) and multivariate (MV) Cox models were used to evaluate the prognostic importance of each baseline factor on OS. Those prognostic factors significant on both UV and MV analyses that were used to develop the scoring system included overall quality of life, age, sex, stage, ECOG performance status, the presence of other cancers, and smoking cessation. The score for each factor was determined by dividing the 5-year OS rate (in %) by 10 and summing these scores to form a total score. Multivariate models and the score for each factor were validated using bootstrapping with 1000 iterations from the original samples. Results: The score for each factor ranged from 1 to 7 points and the total scores ranged between 23 and 39 points. Higher scores reflected better OS. Categorization of the score was delineated first by clinician expert opinion (see Table) and then by multiple statistically defined empirical cut points. All categorization schemes demonstrated successful prognostic power. The bootstrap method confirmed the reliability of multivariate Cox model and score (Spearman correlation coefficient= 0.45). Conclusions: Prognostic factors significantly associated with OS on both UV and MV analysis were used to construct a valid scoring system which can be used to predict survival of NSCLC pts. This scoring system can be used by clinicians in counseling pts and for stratification in future trial design. [Table: see text]

7029 Background: CBP501, a synthetic duodecapeptide, enhances the cytotoxicity of cisplatin in cell lines and xenografts, including NCI-H226 human mesothelioma. CBP501 increases cisplatin influx into tumor cells through an interaction with calmodulin, and inhibits cell cycle progression by abrogating DNA repair at the G2 checkpoint. Phase I clinical trials combining CBP501 with cisplatin alone or with pemetrexed showed acceptable safety profiles and suggested activity. The most common toxicity of CBP501 is infusion-related urticaria, which is easily managed with diphenhydramine. Methods: Chemotherapy-naive patients with unresectable MPM were stratified by histology (epithelioid vs other) and performance status (PS 0-1 vs 2) and randomized 2:1 to Arm A: pemetrexed/cisplatin plus CBP501 25 mg/m2 IV (42 pts planned), or Arm B: pemetrexed/cisplatin alone at standard doses (21 pts planned). Patients continued on treatment until progression or intolerance; no maintenance therapy was delivered. The primary endpoint is progression free survival (PFS) in Arm A; if > 23 of the 42 patients remain free of progression more than 4 months, the combination will be deemed worthy of further study. In addition to standard CT imaging to assess response and PFS, PET scans, pulmonary function tests, and mesothelin levels were performed. Results: Enrollment was completed in October 2011. 65 pts from 14 institutions were randomized, and 63 were treated. Patient characteristics in the two arms were similar and as follows: median age 65, 82% male, 71% epithelioid histology, 8% PS2. Grade 3/4 treatment-related toxicities were uncommon, no different than expected from standard chemotherapy, and comparable in the two arms. 70% of patients treated with CBP501 had infusion reactions, all grade 1-2. The best overall response rate in evaluable patients (modified RECIST, investigator assessed) was 12/37 (32%) (95% CI 18-50) in Arm A, and 3/22 (14%) (95% CI 3-35) in Arm B. The median number of chemotherapy cycles was 5.5 in Arm A, 5 in Arm B. Conclusions: Data on the primary endpoint of PFS in Arm A are maturing and will be presented at the meeting.

LBA8003 The full, final text of this abstract will be available at abstract.asco.org at 7:30 AM (EDT) on Monday, June 3, 2013, and in the Annual Meeting Proceedings online supplement to the June 20, 2013, issue of Journal of Clinical Oncology. Onsite at the Meeting, this abstract will be printed in the Monday edition of ASCO Daily News.

7555 Background: In a retrospective exploratory analysis of E4599, patients (pts) > 70 yo had a higher frequency of and more severe toxicities without apparent survival benefit from the addition of B to C+paclitaxel. We hypothesized that in this pt population, B will have better safety and efficacy profile when used in combination with C+P. Methods: Pts >/= 70 yo with previously untreated stage IIIB/IV (TNM 6th ed) nonsquamous NSCLC, ECOG PS 0-1, measurable disease and adequate organ function were eligible. C at AUC 6, P at 500 mg/m2 and B at 15 mg/kg were administered on day 1 of each 21-day cycle for up to 6 cycles followed by maintenance P+B in patients with CR, PR or SD. The primary endpoint was 6-month progression-free survival (PFS) rate. The treatment would be considered promising based on a single arm one-stage binomial design if 34 or more successes out of 55 patients were observed. This design had an exact significance level of 0.05 at 93% power to detect a true success rate of at least 70%. Polymorphisms in VEGFA, FPGS, GGH, SLC19A1 and TYMS in germline DNA were correlated with treatment outcome. Results: 58 eligible pts were enrolled; 29 males/29 females. Median age was 75. Median treatment cycles received was 6. Grade 3 or higher adverse events (AE) were reported in 49 (85%) pts. There were no treatment-related deaths. The most common grade 3/4 AEs(regardless of attribution) were hypertension (10%), fatigue (28%), dehydration (9%), neutropenia (43%) and thrombocytopenia (21%). There were 3 (5%) grade 3/4 hemorrhagic events. 8 (14%) had grade 4 neutropenia and 3 (5%) had grade 4 thrombocytopenia. Grade 3/4 ischemic/thromboembolic events occurred in 6 pts (10%). Thirty-four out of the first 54 (63%, 95% CI: 48.7-75.7%) evaluable pts met the primary endpoint (4 pts were lost to follow-up prior to 6 months). The confirmed ORR was 37.9% (95% CI: 25.5-51.6%). Median time to treatment failure was 4.8 months (95% CI: 3.9-6.4). Median PFS was 7.1 months (95% CI: 5.9-11.7), median OS was 13.7 months (95% CI: 9.4-15.7). Results of SNP analysis will be presented. Conclusions: C+P+B followed by maintenance P+B is an active and tolerable first-line regimen for elderly patients with good PS.

362 Background: Most pts with mGEA do not respond to ICI or ramucirumab/paclitaxel (RAM/TAX). Emerging data suggest that ICI may potentiate subsequent therapy (Tx). In KN059 we unexpectedly observed durable responses in 2 pts on RAM/TAX after ICI (PMID 29674442). We examined if ICI impacts efficacy of subsequent RAM/TAX in a larger cohort and explored alterations in the tumor microenvironment. Methods: All pts with mGEA at Mayo Clinic (MN, AZ, FL) who received RAM/TAX (2014-19) were included. We compared best objective response rate (ORR: complete [CR] or partial response [PR]) per RECIST1.1 and overall survival (OS) in pts who received RAM/TAX with (Group A) vs without (Group B) immediately preceding PD-1 blockade. Chi square and multivariate logistic and Cox regression were used. We adjusted for total lines of Tx received and the line of Tx in which RAM/TAX was given, to control for potential differences in the biology of heavily treated pts or those receiving RAM/TAX as 2nd vs 3rd line Tx. We also adjusted for age and ECOG PS. Results: In total 87 pts met inclusion criteria. In the 19 pts (Group A) who received RAM/TAX (usually as 3rd line Tx) after progression on ICI, there was a 77% relative risk reduction of death after initiation of RAM/TAX compared to the 68 pts (Group B) who received RAM/TAX (usually as 2nd line) without preceding ICI (median OS 15.0 vs 7.6 mo; HR 0.23; P < .001). The ORR was also significantly higher (58% vs 18%; P < .001) including the CR rate (16% vs 1%; P = .006). Two CRs in Group A are ongoing (10 - 34 mo). Of note, 95% of Group A pts did not respond to ICI, and all had irRECIST progression on ICI. Immunofluorescent analysis from a responder showed 65-fold reduction (post vs pre-Tx) in intratumoral density of immunosuppressive FOXP3+ Tregs, with preserved density of antitumor CD8+ T cells. Conclusions: Higher than expected efficacy was observed on RAM/TAX when immediately preceded by ICI, suggesting ICI may enhance efficacy of subsequent anti-VEGFR/taxane therapy. This serial immunotherapy combination may be a novel option for pts with primary resistance to ICI and will be tested prospectively in a new randomized phase 2 trial (NCT04069273).

Objective:Radiation therapy (RT) is the primary treatment of intracranial metastasis (ICM) from lung cancer (LC). Radiation necrosis (RN) has been reported post-RT with an incidence of 5% to 24%. We reviewed the spectrum of imaging changes in patients treated with RT for ICM from LC in an effort to identify potential risk factors for RN.Methods:We reviewed 63 patients with LC and ICM who received RT (radiosurgery [stereotactic radiosurgery] with/without whole brain radiation therapy) at our institution between 2013 and 2018. Data evaluated included demographics, tumor type, ICM burden and location, chemotherapy, surgery, and RT details as well as treatment choices and outcomes.Results:Of the 63 patients, clinical and radiographic criteria for RN were noted in 24 (38%) as early as 2 months and as late as 5 years posttreatment. Six patients required surgical resection due to refractory symptoms revealing pathology-proven RN and occasionally tumor. Patients were significantly more likely to develop RN if they had surgical resection of an ICM (45.8% vs. 20.5%,P=0.05). No differences were found in location, size, or genetic profile of lesions. In total, 80% of patients received treatment for symptoms and/or radiographic change. This was generally a combination of steroids, bevacizumab, laser interstitial thermal treatment, or surgical resection. Most patients required >1 treatment modality.Conclusions:This review of outcomes of RT for ICM in LC demonstrates a higher rate of RN than previously reported in the literature in those having had a surgical resection plus stereotactic radiosurgery. Our observation of RN as late as 5 years post-RT for ICM necessitates clinician awareness.

Abstract Cancer transmission with organ donation has been previously reported with a variety of malignancies and organ transplants. The risk of transmission through organ transplantation from donors with a history of previously treated malignancies has been addressed by guidelines from transplant societies. Herein, we report a case of a patient who developed lung cancer confined to the liver after liver transplantation with no known history of malignancy in the donor. The suspicion of donor origin arose after positron emission tomography-computerized tomography scan showed metastatic lung cancer only involving the transplanted liver without a primary focus. Genetic analysis of the malignant cells confirmed donor origin of the cancer.

159 Background: Intensity-modulated proton therapy (IMPT) with small spot size has the potential to reduce dose to normal tissues but also introduces new confounding factors such as setup uncertainty, range uncertainty, and interplay effects due to breathing motion. We investigated plan quality and robustness of IMPT with small spot size for distal esophageal adenocarcinoma (DEA). Methods: 19 patients with DEA treated by IMPT were retrospectively evaluated. Spot sizes ranged from 2 to 6mm, with spot spacing of 5mm. All plans were generated using a commercial treatment planning system. In-house-developed dose-evaluation software modeled time-dependent spot delivery to incorporate interplay effects. Dose-volume-histogram (DVH) indices were used to evaluate plan quality and robustness was evaluated using the DVH band method. Results: For plan quality, median values of clinical target volume D95% and D5%-D95% (normalized to the prescribed doses), total lung mean dose, heart mean dose, and cord Dmax were 1.014, 0.035, 3.82Gy[RBE], 7.73Gy[RBE], 39.16Gy[RBE], respectively. For plan robustness, median band widths of the aforementioned DVH indices were 0.018, 0.048, 0.60Gy[RBE], 4.17Gy[RBE], and 2.36Gy[RBE], respectively. For interplay effects, median values of the aforementioned DVH indices were 0.99, 0.061, 4.07Gy[RBE], 7.87Gy[RBE], and 39.66Gy[RBE], respectively. Seven patients underwent esophagectomy after neoadjuvant chemoradiation, and five, three, and one of them achieved downstaging, near complete response, and pathologic complete response, respectively; R0 resection was achieved in all cases. For all patients, acute side effects were mostly limited to grades 1-2 only. The only grade 3 adverse events were related to feeding tube placement (8 patients); there were no RT-induced pneumonitis or other lung-related toxicities. Conclusions: IMPT plans with small spot size for DEA have good target dose coverage, homogeneity and normal tissue protection. Treatment plans are also robust to uncertainties and interplay effects. Early clinical results demonstrate low acute toxicity and encouraging clinical and pathologic response.