Rectal carcinoma-squamous type is infrequently seen. Etiopathogenesis, prognosis, and therapeutic management of rectal squamous cell carcinoma (SCC) are not clearly defined. Rectal SCC is now approached with definitive upfront chemoradiotherapy (CRT), with 5-fluorouracil (5-FU) and mitomycin with a goal to avoid surgery. However, its management is planned based on histology features regardless of the localization of SCC rectal cancer. We present a case of a 47-year-old Caucasian female with rectal SCC who is under remission for two years after being treated with upfront chemoradiation with mitomycin and 5fluorouracil (5-FU).

e21213 Background: Lung cancer is the leading cause of death in males and females in the United States. Approximately 85% of all cases are classified as non-small cell lung cancer (NSCLC) with majority diagnosed at an advanced stage. Unfortunately, response to traditional chemotherapy (ChT) has been poor with a five-year survival rate of 6% in metastatic NSCLC. Immune checkpoint inhibitors (ICI) have changed the therapeutic landscape for advanced NSCLC and are being utilized alone or in combination with ChT as the standard first-line therapy. With widespread use of ICIs, immune-related adverse events (irAE) are commonly seen and in some studies their occurrence correlates with improved outcomes. The aim of our study was to evaluate whether development of irAEs has an impact on survival in NSCLC. Methods: We performed a retrospective analysis on stage IV NSCLC patients treated with ChT, ChT plus ICI, or ICI monotherapy from December 2016 to December 2019. Univariable and multivariable analyses identified characteristics predictive of progression-free survival (PFS) and overall survival (OS). OS was calculated using Kaplan Meier curves. Log-rank statistics were used to assess statistical significance between groups. Multivariable logistic regression was performed to identify predictors of survival. Results: 193 patients were evaluated out of which 92 (47.2%) received ChT plus pembrolizumab, 69 (35.4%) received pembrolizumab alone and 32 (16.4%) received ChT alone. 130 patients were found to have no irAEs compared to 57 patients who were noted to have any grade of irAE. The median PFS was 17.4 months (irAE group) vs. 8.5 months (non-irAE group) with hazard ratio (HR) of 0.58 (95% CI: 0.41 to 0.80, p = 0.001). The median OS was 29.4 months (irAE group) vs. 14.4 months (non-irAE group) with HR of 0.56 (95% CI: 0.39 to 0.82, p = 0.0026). A multivariate analysis was performed for age, gender, ECOG performance status, insurance status, BMI, PDL1 status and smoking history, amongst other variables. Worse survival outcomes were noted with an ECOG performance status ≥ 2, no history of smoking, and involvement of palliative care. Multivariable logistic regression analysis showed that PDL-1 expression > 50% was the only predictor of developing an irAE. Of note, receipt of ChT in combination with pembrolizumab compared to pembrolizumab alone did not predict for development of irAE. Conclusions: Development of irAEs was associated with doubling of PFS and OS, regardless of whether the ICI was administered alone or in combination with ChT. The differences were statistically significant regardless of age, gender, race, BMI, insurance status or performance status. Our study highlights the correlation between development of irAEs and improved survival outcomes in advanced NSCLC patients treated with ICIs.

Fluoropyrimidines (FP's) such as fluorouracil (5-FU) and capecitabine are antimetabolites widely used in many solid tumors. FPs side effects are caused mainly by a lack of dihydropyrimidine dehydrogenase (DPD) enzyme. It has been noticed that treatment with infusional regimens of 5-FU is associated with more adverse events (AE) compared to bolus forms. Here, we report two cases of unusual side effects seen with infusional 5-FU and capecitabine and how early intervention by withholding ongoing treatment can help in preventing progression and mortality.

Lung adenocarcinoma or non-small cell lung cancer (NSCLC) represents one of the most diagnosed cancers worldwide. Anaplastic lymphoma kinase (ALK) mutation, a tyrosine kinase and ALK fusion or rearrangement oncogene, has been found rarely in patients with NSCLC. Newer treatment modalities with different ALK inhibitors in targetable specific ALK mutations have recently made great strides in the management of NSCLC patients. We present a case of NSCLC harboring ALK mutation with primary cutaneous marginal zone B-cell lymphoma (PCMZL) treated with adjuvant chemotherapy with pemetrexed and cisplatin, and ALKechinoderm microtubule-associated protein-like 4 (EML4)-targeting treatment alectinib.

e21084 Background: Lung cancer remains the most commonly diagnosed cancer in the United States, as well as the leading cause of cancer-related mortality. Approximately 84% of all lung cancers are non-small cell lung cancer (NSCLC). Most are diagnosed at an advanced stage when the prognosis is poorest. EGFR is the most common driver mutation in NSCLC with an incidence ranging from 20% in Caucasians, and up to 50% in Asians. Oral tyrosine kinase inhibitors (TKI) are the preferred treatment for EGFR mutant cancers as they provide better outcomes and lower toxicity than chemotherapy (Ch) or immunotherapy (ICI). Therefore, it is imperative to analyze NSCLC patients for these important driver mutations. Cancer care is expensive with the treatments and attendant costs for administration and management. We sought to compare cost of care (COC) in EGFR mutant vs wild-type NSCLC as the treatments and known toxicities differ markedly. Methods: We performed a retrospective COC analysis of NSCLC using claims data from the local BCBS affiliate Highmark (HM) members. Patients were selected based on NSCLC diagnosis codes between October 2016 and September 2018. COC was calculated from claims data to compare treatment of driver mutant NSCLC with targeted therapy versus treatment of wild-type NSCLC with ICI and/or ChT. Data used to compare COC analysis included overall medical costs defined as all medical claims incurred by a patient following start of respective therapy, oncology related medical claims, therapy costs, costs related to emergency room visits and tissue biopsies. Overall medical costs, oncology related costs and therapy costs were measured in per member per month (PMPM). We extracted cost related data at 6 months, 12 months, and 18 months into treatment. Results: Patients treated with ICI and/or ChT incurred $1000-2000 more in PMPM total medical costs than patients treated with targeted therapy. Additionally, chemoimmunotherapy patients were found to have a 5% higher emergency room admission rate along with a longer median length of stay of 1/3 day, when compared to targeted therapy patients. ICI and/or ChT patients showed a 20% higher rate of tissue biopsy and a 5-10% higher rate of repeat tissue biopsy which incurred an additional $300-$400 expense for chemoimmunotherapy patients. Conclusions: The use of targeted treatment with TKIs in EGFR mutant NSCLC patients is more cost effective than ICI and/or ChT in wild-type NSCLC. Routine screening of lung cancer patients with molecular profiling is essential, as identification of such critical driver mutations can alter the treatment plan to be more efficient, providing better care at lower cost.