(1) Background: Small bowel adenocarcinoma (SBA) is one of the predominant primary small bowel cancers that has a dismal outcome. We aim to report 10 years of experience in SBA management at a regional cancer centre in Canada.; (2) Methods: We retrospectively analysed clinical and pathological data of patients diagnosed with an SBA between 2011 and 2021 at the Ottawa Hospital (TOH), Ottawa, Canada. We describe the clinicopathological features and outcomes, including survival. Potential prognostic factors were analysed using the Cox proportional hazard model for multivariate analysis.; (3) Results: We identified 115 patients with SBA. The duodenum was the most common SBA location representing 61% (70) of the total patients, followed by the jejunum (17%) and ileum (10%). Around 24% (27) of cases presented with bowel obstructions. The majority of patients (56%, 64) had stage IV disease on presentation. Seven patients had MSI-high tumours, while 24% (27) were MS-stable. In terms of management, 48 patients underwent curative surgical resection, 17 of whom received adjuvant chemotherapy. On the other hand, 57 patients (49.5%) with the advanced disease received palliative systemic therapy, and 18 patients (16%) had supportive care only. Over a median follow-up of 21.5 months (range 0–122), the median overall survival was 94, 61, and 34 months for stages II, III, and IV, respectively (p < 0.05). The median recurrence-free survival was 93 and 23 months for stages II and III, respectively. However, there was no statistically significant difference between TNM stages in RFS, p = 0.069. Multivariate Cox regression analysis showed only poor performance status at diagnosis as a predictor for shorter overall survival (p < 0.05). The univariate analysis didn’t show any significant correlation between RFS and covariants.; (4) Conclusions: SBA remains one of the most aggressive tumours with a dismal prognosis even after surgical resection. The optimal chemotherapy regimen has not been established. Further studies are needed to explore the role of adjuvant chemotherapy for stages I-III SBA.

(1) Background: The management of gastrointestinal stromal tumors (GIST) has significantly evolved over the last two decades, with the introduction of tyrosine kinase inhibitors (TKI). We aim to report 10 years of experience of GIST management at a regional cancer center in Canada. (2) Methods: We retrospectively analyzed the records of 248 consecutive patients diagnosed with GIST between 2011 and 2021. We describe the clinical and pathological data, management, and outcome, including survival. (3) Results: The most common GIST sites were the stomach 63% (156), followed by the small bowel 29% (73). At diagnosis, 83% (206) of patients had localized disease (stage I–III). According to the modified National Institutes of Health consensus criteria (NIH) for GIST, around 45% (90) had intermediate or high-risk disease. Most patients, 86% (213), underwent curative surgical resection. Forty-nine patients received adjuvant imatinib, while forty-three patients had advanced disease and received at least one line of TKI. With a median follow-up of 47 months, the 5-year recurrence-free survival (RFS) rates for very low and low risk were 100% and 94%, respectively, while those for intermediate and high risk were 84% and 51%, respectively. The 5-year overall survival (OS) rates for very low and low risk were 100% and 94%, while intermediate, high risk, and advanced were 91%, 88%, and 65%, respectively. Using the Kaplan–Meier method, there were statistically significant differences in RFS and OS between NIH risk groups, p < 0.0005. In univariate analysis, ECOG, site, mitosis, secondary malignancy, and size were predictors for OS. High mitosis and large size (>5 cm) were associated with worse RFS. (4) Conclusions: Curative surgical resection remains the gold standard management of GIST. Our results are comparable to the reported literature. Further research is needed to explore histology’s role in risk stratification and initiating adjuvant TKI.

(1) Aim: The prevalence and incidence of small bowel NETs have increased significantly over the past two decades. This study aims to report the 10-year experience of SB-NET management at a regional cancer center in Canada. (2) Materials and methods: We conducted a retrospective study of the clinical and pathological data of patients diagnosed with biopsy-proven SB-NET at The Ottawa Hospital (TOH), Ottawa, Canada between 2011 and 2021. We report the clinicopathological characteristics of these patients, as well as their outcomes data, including survival rates. (3) Results: Between 2011 and 2021, a total of 177 SB-NET cases were identified with 51% (n = 91) of cases being males. The most common sites of the tumors were the ileum 53% (n = 94), followed by the duodenum 9% (n = 16) and jejunum 7% (n = 12). Approximately 24% (n = 42) of the patients had symptoms for over six months prior to diagnosis and 18% (n = 32) had functioning SB-NET during the course of the disease. The majority of patients had locally advanced or metastatic disease at the time of presentation with stage III, and stage IV representing 42% (n = 75), and 41% (n = 73) respectively. The majority of patients 84% (n = 148) had well-differentiated histology. One hundred twenty patients underwent surgical resection of the primary tumor including 28 patients (16%) with limited metastatic disease. A total of 21 patients (18%) had recurrence after curative surgery. A total of 62 patients (35%) received first-line somatostatin analog (SSA) therapy for unresectable disease and seven patients had PRRT after progression on SSA. Five years OS was 100%, 91%, 97%, and 73% for stages I, II, III, and IV respectively. In univariate analysis, carcinoid symptoms, T stage, and differentiation were significant predictors for worse overall survival, but not RFS. (4) Conclusions: Compared to published historical controls, our study suggests improvement in the 5-year survival rate of SB-NETs over the last 10 years.

11536 Background: The secondary malignancies in patients with GIST are relatively high. We present our 10-year experience of SPM in patients with GIST from a regional Cancer Centre in Canada. Methods: A retrospective cohort study was performed in all GIST patients treated at TOH between January 2011 and December 2021. Patients were identified using ICD-10 codes and electronic medical records reviewed. Clinicopathological data were analyzed. Logistic regression analysis was used to evaluate associated factors with SPM. Survival analysis was estimated with the use of the Kaplan-Meir method and compared by log-rank test. Results: In total, 248 patients with GIST were identified. Of these patients, 61 (25%) had SPM; synchronous (9, 15%) and metachronous (52, 85%). Nine patients had two additional primary cancers other than GIST, and four patients had three additional primary cancers. The median age at diagnosis was 70 (range 44 – 90) years, and males were (59%). The most common SPMs were skin cancer (14, 17%), melanoma (5), and non-melanoma (9), followed by prostate cancer (13, 16%) and breast cancer (12, 15%). Colorectal cancer and hematological malignancies were found in (5, 11%) patients each, while RCC was found in (4, 6%). Thyroid cancer, lung cancer, neuroendocrine tumor, bladder cancer, thymoma, and other types of cancers were collectively found in 15 patients (24%). The majority (57%) of SPM diagnosed before GIST, 30% after GIST. The most common primary GIST locations were in the stomach (62%), followed by the small bowel (30%), and the most common histology was spindle cell (69%), followed by mixed histology (13%). The majority of GIST were localized (46 patients, 75%). Based on Miettinen risk classes for non-metastatic GIST, 74% had zero to low-risk disease, while 26% had moderate or high-risk disease. There was no association between SPM and GIST primary site (p = 0.4), TNM stage (p = 0.8), histology (p = 0.2), Mitosis (p = 0.5), and Miettinen risk class (p = 0.6). The median follow-up time was 53 months (range 1 – 132), and four patients lost follow-ups. Five years overall survival of SPM group vs. non SPM, 79.8% vs. 94.1%, (p = 0.03). Cox regression did not reveal a significant association with the covariants Conclusions: We observed that one out of four GIST patients have SPM. Skin, prostate, breast cancers were the most common SPM associated with GIST. Molecular studies are needed to explore the association/underlying mechanisms of GIST with these malignancies.

Nasopharyngeal cancer (NPC) is common in Saudi Arabia; Most cases are related to the Epstein‐Barr virus (EBV), which is associated with treatment failure and a high recurrence rate. Programmed cell death protein 1 (PD‐1) and Programmed death‐ligand 1 (PD‐L1) inhibitors emerged as breakthroughs in cancer treatment, including head and neck cancers. The benefit of these therapies was seen in patients with high expression of PD‐L1, which is unknown in our population.  We aim to assess PD‐L1 expression in EBV‐related NPC patients presented to King Fahd Medical City (KFMC). We identified 41 cases of EBV‐related NPC diagnosed between 2016 and 2019. PD‐L1 expression was assessed using the Tumor Proportion Score (TPS) and Combined Positive Scores (CPS). Results showed that PD‐L1 expression was negative in 51% and 29% using TPS and CPS scores, respectively. High expression of PD‐L1, more than 50%, was seen in 17% using TPS and 22% using CPS. There was no statistically significant correlation between the degree of PD‐L1 expression by TPS or CPS and many variables, including gender, comorbidities, BMI, TNM staging, and smoking status. Over a median follow‐up of 29.7 months, Kaplan‐Meier survival curves did not show a statistically significant difference between all groups of PD‐L1 expression for O.S. or PFS; However, there were shorter O.S noted with CPS 1%–9%, log‐rank p‐value = 0.031. These findings support investigating the role of Immunotherapy, especially in the high expression subgroup. Data for these patients' outcomes and further studies to explore the role of PD‐L1 in NPC are needed.