Kadakia, Kunal C.

231 Background: The recent development of KRAS G12C inhibitors underscores the potential to target KRAS mutations. Right-sided and left-sided colon tumors (RT and LT) exhibit different molecular features. We characterize the prevalence of KRAS-variants, interrelation with primary tumor location, and association with immune biomarkers in CRC. Methods: We retrospectively reviewed CRC tumors of all stages (with known sidedness) that underwent NGS with the Tempus xT assay (DNA-seq of 648 genes at 500x coverage, full transcriptome RNA-seq). Bivariate analyses were performed to compare KRAS alterations, immune biomarkers, and co-mutations by tumor location. P-values comparing individual co-mutations between groups were adjusted for false discovery (FDR). Results: A total of 3,391 CRC were analyzed (RT: n = 442 [13%], transverse: n = 116 [3%], LT; n = 2,833 [84%]) of which 1486 (44%) tumors harbored KRAS mutations. Overall, KRAS mutations were more frequent in RT compared to transverse tumors and LT (52% vs 41% vs 43%, p<0.001, respectively). The most frequent KRAS mutation variants observed were G12D (29 %), G12V (22%), G13D (16%), and G12C (5.7%). There was no significant difference in the prevalence of KRAS variant types between LT and RT (p=0.5). Significant differences in genomic co-mutations with various KRAS variants were observed in the following genes: TP53, FBXW7, and NF1 (FDR- P<0.05). RT and transverse tumors were more likely have MSI-H and TMB-H (>10 mut/mb) status than LT (MSI-H: 18% vs 22% vs 2.2% and TMB-H (20% vs 22% vs 3%, P<0.001), respectively. CRC tumors harboring G13D variants were more likely to be associated with and MSI-H and TMB-H status (and 7.7% and 8.5%) compared to G12D (2.8 % and 3.9 %), G12V (1.8 % and 2.1%), and G12C (0% and 2.4%); P = 0.003 and 0.001. Conclusions: The most frequent KRAS mutation variants observed in CRC tumors were G12D, G12V, G13D, and G12C. There was no significant difference in the prevalence of KRAS variant types between tumors of the left vs right colon. CRC tumors that harbored G13D variants were significantly more likely to be associated with MSI-H and TMB-H status. [Table: see text]

e20605 Background: Intravenous (IV) fosaprepitant is a potent antiemetic, commonly used in patients receiving chemotherapy. The purpose of this study was to investigate the incidence of IV fosaprepitant-associated infusion site adverse events (ISAEs) among a cohort of breast cancer patients receiving doxorubicin and cyclophosphamide (AC) chemotherapy at Mayo Rochester. Methods: A retrospective review of electronic medical record (EMR) data was performed for all patients who were initiated on AC chemotherapy from January 2011 to April 2012. Data collected from the EMR included baseline demographics, antiemetic regimen, documentation of ISAEs and type of IV access (peripheral vs. central). Descriptive statistics (mean and standard deviation or percentages) were summarized overall and by type of IV access and initially administered antiemetic. Results: 148 patients were included, with a median age of 54 years (range 28-76). 98 patients initially received IV fosaprepitant; 44 oral aprepitant; 6 neither. 132 (89%) initially had peripheral IV access and 16 (11%) had central venous access. Overall, 33 patients (34%) experienced an IV fosaprepitant associated ISAE including: erythema (n=22), pain (n=26), swelling (n=12), infusion site hives (n=5), extravasation (n=4), deep venous thrombosis (n=3), superficial thrombosis (n=7), phlebitis/thrombophlebitis (n=5), venous discoloration (n=1), venous engorgement (n=1), venous hardening/induration (n=4) and local scarring (n=1). Only 1 patient (2%) experienced an oral aprepitant associated ISAE, which was infusion site pain. This patient had previously had a fosaprepitant associated ISAE at the same site. All experienced ISAEs occurred in patients with peripheral IV access. Conclusions: The incidence and severity of ISAEs associated with IV fosaprepitant administration among a group of patients receiving doxorubicin/cyclophosphamide chemotherapy is significant and is appreciably higher than what has been noted in other reports. The higher incidence observed is likely related to the predominance of peripheral venous access used in the studied cohort.

e17538 Background: Adherence to guideline-consistent chemotherapy-induced nausea and vomiting (CINV) prophylaxis is suboptimal. The primary aim of this study was to evaluate the magnitude of compliance to institutional guideline-directed antiemetic prophylaxis using a computerized physician order entry system at a single tertiary care institution. A nurse survey was also performed to evaluate how oncology practices, within a cooperative group, manage clinician orders for the prevention of CINV. Methods: The electronic medical records of 100 consecutive patients were evaluated. The primary endpoint was the incidence of compliance to provide all aspects of institutional guideline-directed antiemetic prophylaxis for acute (Day 1) and delayed (Days 2-4) CINV for patients receiving high, moderate, low, and minimally-emetogenic chemotherapy (HEC/MEC/LEC/MinEC). Noncompliance was declared if a recommended antiemetic was not prescribed per the guidelines or if additional antiemetics were prescribed. Descriptive analyses were performed on the convenience sample. Logistic regression was applied to determine the association of potential factors with noncompliance. Results: The incidence of compliance on Days 1-4 was 94%. Half of the noncompliant events occurred on Day 1 alone and involved the omission of pre-chemotherapy prochlorperazine in patients receiving LEC (3 of 6, 50%). There was a high-degree of compliance to institutional guidelines for delayed CINV (97%). Patients receiving doxorubicin/cyclophosphamide were numerically less likely to receive institutional guideline-directed antiemetic prophylaxis, compared to patients receiving other chemotherapy regimens (OR: 0.24 (0.04, 1.36), p-value: 0.05). No other factors were significantly predictive for compliance. The nurse survey demonstrated significant variability amongst the involved institutions, with regards to antiemetic prescribing practices. Conclusions: Computerized physician order entry is associated with impressive adherence to clinician prescribing practices, according to institutional guideline-directed antiemetic prophylaxis, for preventing acute and delayed CINV.

Diffuse pulmonary lymphangiomatosis (DPL) is a rare disease characterized by infiltration of the lung, pleura and mediastinum with thin-walled lymphangiomas. DPL can result in mass effect from infiltrative disease, restrictive and obstructive pulmonary physiology, chylous effusions and respiratory failure. The present article discusses clinical, radiographic and pathological features, and treatment options for DPL.