Citations

Abstract Objectives: infection with the bacteria Helicobacter pylori has been classified as class 1 carcinogen associated with increasing susceptibility of gastritis and gastric carcinoma. This study is aiming at investigating the prevalence of H. pylori in colon polyps and colon cancer lesions. A descriptive cross-sectional hospital-based study was conducted between February and June 2017. Sixty-nine formalin fixed paraffin blocks from colon polyps and colon cancer lesions to detect H. pylori using immunohistochemistry technique.Results: Of the Sixty-nine patients included in the study, 39 (56.5%) males and 30 (43.5%) were females, their age ranged from 21 to 80 years with a mean age of 47.1 ± 19.7. Of the 69 colon polyps and colon cancer cases, 44 (63.8%) were diagnosed as adenocarcinoma, 10 (14.5%) colitis, 15 (21.7%) juvenile polyposis syndrome. The results of immunohistochemistry technique showed the presence of 16 (23.2%) positive patients for H. pylori infection. Of these 16, 13 (81.3%) patients were off those diagnosed with adenocarcinoma and the remaining 3 (18.7%) patients were diagnosed with juvenile polyps. the results of H. pylori detection among the different colon polyps and colon cancer diagnosis was showing a statistically significant association for H. pylori infection and adenocarcinoma, P value 0.028.

e20044 Background: Primary Cutaneous Diffuse Large B-cell Lymphoma, Leg-type (PCDLBCL) is a rare lymphoma comprising 4% of all cutaneous lymphomas with an aggressive clinical course. We investigated disease characteristics and outcomes among patients PCDLBCL. Methods: Following IRB approval, we identified patients retrospectively with PCDLBCL treated at the Mayo Clinic Cancer Center 1998-2019. Results: 45 pts were identified with a median age of 71 years (Range- 48-95) and 28 (62%) were female. Disease locations were legs (62%), arms (22%), head (11%), trunk (2%) and multiple sites (2%). At diagnosis, (51%) had a single lesion, (29%) had multiple lesions in 1-2 contiguous regions, (16%) had multiple lesions in non-contiguous regions or > 2 regions and data was not available (4%). Immunohistochemistry showed positive staining for BCL-2 (92%), BCL-6 (76%), c-MYC (62%), MUM1 (95%), CD10 (11%), and cytoplasmic IgM (8/9- 89%). By Han’s criteria, (95%) had activated B cell lymphoma (ABC). Median Ki-67 was 90% (range, 50,100%). 9/12 (75%) were positive for MYD88 L265P mutation. 13/21 (62%) were double expressor and 3/22 (14%) had double hit lymphoma. 37/45 (82%) had ECOG < 2. LDH was elevated in 13/37 (35%). The median number of therapies was 1 (range; 1-11). The initial treatments were chemo-radiation (30%), chemo alone (38%), rituximab alone (11%), radiation (RT) alone (16%), rituximab-RT (2.5%), and surgical (2.5%). The median follow-up time for the whole cohort was 80 months (95% CI; 32, 169). The median progression free survival and overall survival (OS) were 20 months (95% CI; 12, 34) and 80 months (95% CI; 48, 119). 22/45 (49%) are alive. The cause of death was disease-related in 11/23 (48%). The median number of relapses was 1 (range; 0, 11) with (60%) relapsed after first line. 4/45 pts had autologous stem cell transplant after relapse. 7/45 (16%) had a systemic relapse at a median time of 35 months from diagnosis (range; 16, 112). Age above 60 years was associated with worse OS; 70 months (95% CI; 30, 99) vs NR (95% CI; 135, NR), p = 0.025. ECOG performance status < 2 was associated with better OS, NR months (95% CI; 80, NR) vs 48 months (95% CI; 3.3, 88),p = 0.0003. 1 pt received Ibrutinib on 11th relapse and had 3 years of PFS. Conclusions: PCDLBCL is predominantly ABC type, affects elderly pts and is characterized by multiple cutaneous relapses followed in some cases by systemic relapses. Increased age and poor performance status had a negative impact on OS. High incidence of MYD88 L265P mutation is observed in PCDLBCL similar to immune-privileged site lymphomas.

e20036 Background: Hepatosplenic T cell lymphoma (HSTL) is a rare subtype of mature T cell lymphomas accounting for less than 1 percent of non-Hodgkin lymphomas. it has been associated with poor prognosis. It typically involves sinusoids in the spleen, liver, and bone marrow. Methods: Following IRB approval, we retrospectively evaluated patients with HSTL treated at the Mayo Clinic Cancer Center 1996-2019. Kaplan-Meier survival analysis and univariate analysis to identify prognostic factors were performed. We investigated clinical characteristics and outcomes among patients with HSTL. Results: 22 patients (15 males) with median age of 45.5 years (range- 15.5-80.6) were identified. The majority of patients had B symptoms (12/22), cyotpenias (20/22), massive splenomegaly (16/22), liver involvement (13/22), and/or bone marrow involvement (14/22). Additionally, 42% tested positive for peripheral blood involvement and 8/22 (36%) were on chronic immunosuppression related to solid organ transplant (2), inflammatory bowel disease (2), and rheumatologic disorders (4). Phenotypically, the majority of patients were positive for gamma/delta (18/22), isochromosome 7q (8/13), and 4/9 (44%) tested positive for trisomy 8. Initial therapies included CHOP/CHOEP (14), ICE (2), EPOCH (1), pentostatin (1), and radiation (1). The median follow-up was 33 months (range 2,137). Progression free survival and overall survival (OS) were 9.5 months (95% CI; 1.8, 16.3) and 12 months (95% CI; 4.9, 18.5) respectively. 10/22 (45%) underwent splenectomy with one patient receiving splenectomy alone as treatment. 8/22 (36%) had stem cell transplant (SCT- 5 allogeneic and 3 autologous). Out of the 22 patients 4 (18%) were long-term survivors with 55, 74, 95, and 137 months; 3/4 had splenectomy at diagnosis and 2/4 had allogeneic SCT. The longest survivor had splenectomy only. Liver involvement was associated with worse OS; 10 months (95% CI; 1.6, 18) vs 35 months (95% CI; 4, NR), p = 0.036. Immune suppression at diagnosis was associated with worse OS; 5 months (95% CI; 1.3, 18) vs 18 months (95% CI; 9, 74), p = 0.036. A trend for better OS was seen with splenectomy and SCT. Conclusions: HSTL is a rare lymphoma with poor prognosis. Long-term survival was seen in 18% only. Liver involvement and immune suppression had a negative impact on OS. A larger cohort is needed to better evaluate the impact of different treatment options.

e17540 Background: The clinical course in metastatic castrate-resistant prostate cancer (mCRPC) can be complicated when patients have disease progression after treatment with 2nd generation hormone therapy (2nd-HT), such as enzalutamide or abiraterone. Currently, limited data exist regarding the optimal choice of chemotherapy for mCRPC after failing 2nd-HT. We sought to evaluate three common chemotherapy regimens in this setting. Methods: We retrospectively identified 150 patients with mCRPC with disease progression on enzalutamide or abiraterone. 92 patients were chemo-naïve, while 58 patients had previously received docetaxel chemotherapy prior to 2nd-HT. After failing 2nd-HT, 90 patients received docetaxel-alone (group A), 33 patients received carboplatin plus docetaxel (group B), while 27 patients received cabazitaxel-alone (Group C). Favorable response was defined by ≥50% reduction in PSA level from baseline after a complete course of chemotherapy. Survival outcome was assessed for 30-month overall survival. Results: Mean (SD) age was 71.2 (8.28), 69.5(8.38) and 67.2 (8.36) for group (A), (B) and (C), respectively. Mean (SD) pre-chemotherapy PSA was 63.8 (138.18), 58.5 (118.15) and 53.7 (88.15) for group (A), (B) and (C), respectively. Mean (SD) Gleason score was 7.9 (1.1), 8.4 (0.88) and 8.1 (1.06) for group (A), (B) and (C), respectively. Patients in group (B) were 2.6 times more likely to have a favorable response compared to group (A) (OR = 2.625, 95%CI: 1.15 - 5.99) and almost 3 times compared to patients in group (C) (OR = 2.975, 95%CI: 1.04 – 8.54) (p-value = 0.0442). We report a Hazard Ratio (HR) of 3.1 (95% CI 1.31-7.35; p = 0.0037) between patients in group (A) versus group (B), and a HR of 4.18 (95% CI 1.58-11.06; p = 0.0037) between patients in group (C) versus group (B). Thirty-month overall survival was 70.7%, 38.9%, and 30.3% for group (B), (A), and (C) respectively (p-value = 0.008). Conclusions: Our data demonstrate improved response and cancer-specific survival in patients with treatment-refractory mCRPC on docetaxel plus carboplatin compared to docetaxel or cabazitaxel alone. Selection bias is inherent in any retrospective study; however, our finding suggests that clinicians may consider docetaxel plus carboplatin in mCRPC patients who fail 2nd-HT. Further prospective studies are warranted.

5577 Background: Prostate specific antigen (PSA) has well-recognized limitations as a marker for treatment response and disease progression. A post hoc analysis of the PREVAIL trial reported 24.5% of chemotherapy naïve mCRPC patients on enzalutamide had radiographic progression on conventional imaging with non-rising PSA. In this study, we sought to retrospectively compare PSA levels with C-11 choline positron emission tomography/ computed tomography (PET/CT) images in patients with m-CRPC on 2nd-HT with prior use of chemotherapy. Methods: We identified 123 patients with mCRPC on 2nd-HT following prior use of docetaxel chemotherapy (Abiraterone, n = 106; Enzalutamide, n = 17). Patients underwent serial PSA testing and C-11 choline PET/ CTs every 3–6 months. Disease progression was defined by the increase in blood pool corrected maximum standardized uptake value (SUVmax) of the index lesion on C-11 choline PET/CT scan. Suspicious lesions were confirmed by biopsy and/or conventional imaging. Results: Approximately 43% (n = 53) of patients had radiographic disease progression while on 2nd-HT. At time of radiographic progression, 60.4% of patients showed a parallel rise in PSA (Group-A), while 39.6% showed a paradoxical response; defined as radiographic progression with stable or down-trending PSA (Group-B). Median PSA at time of progression was 3.1 ng/ml for Group-A, and 1.3 ng/ml for Group-B (p-value = 0.0176). Median SUVmax was the same (4.9 Group-A, 4.6 Group-B; p-value = 0.6072). Bone-predominance progression was more significant in Group-B (90%) versus Group-A (65%) (p-value = 0.0309). The median time for radiographic progression was 9.5 months versus 3.9 months for Group-A and Group-B, respectively (Log-Rank = 0.0063). Conclusions: Metabolic imaging is a useful tool that should complement PSA in the evaluation of treatment response and disease progression in mCRPC patients on 2nd-HT, especially considering the paradoxical response observed in our data.

e16662 Background: Cholangiocarcinoma (CCA) is a relatively rare malignancy accounting for 3% of gastrointestinal cancers in the US. While multiple risk factors for CCA are established and well-studied, other potential risk factors are still controversial and not well established. Herein, we used a large national database to investigate possible risk factors and associations. Methods: We used the National Inpatient Sample (NIS) database to review all admissions between 2011 and 2015. We grouped patients based on the presence and absence of CCA using the appropriate ICD-9 codes. We used multivariate logistic regression to assess the association between obesity, alcohol abuse, smoking, diabetes mellitus (DM), and non-alcoholic fatty liver disease (NAFLD). Results: We reviewed 30,955,295 admissions of which 20,030 had CCA. CCA Patients were older compared to the rest of the patients (mean age 67 years ±12.8 vs. 57±20.6, P < .001) and had less female patients (48% vs 59%, P < .001). Patients’ characteristics are shown in the table. After adjusting for viral hepatitis B (HBV), viral hepatitis C (HCV), liver cirrhosis, inflammatory bowel disease (IBD), primary sclerosing cholangitis (PSC), and bile duct stones, logistic regression showed DM to be proportionately associated with CCA (OR = 1.04, 95%CI[1.01-1.08], P < .001), whereas alcohol, smoking and obesity were all inversely associated with CCA; OR = 0.75, 95%CI [0.69-0.81], P < .001, OR = 0.75, 95%CI [0.71-0.79], P < .001 and OR = 0.71, 95%CI [0.67-0.75], P < .001, respectively. In addition, compared to whites, Hispanic and Asian/Pacific Islander races were proportionally associated with CCA; OR = 1.27, 95%CI [1.21-1.34], P < .001, and OR = 1.79, 95%CI, [1.67-1.92], P < .001, respectively, while black race was inversely associated with CCA (OR = 0.85, 95%CI [0.81-0.89], P < .001). Conclusions: In our large database study, we found that patients with diagnosis of DM or being from certain minority ethnic groups are associated with increased incidence of CCA. Other factors like alcohol and smoking were associated with decreased incidence of CCA, but those factors may be under reported. This raises the need for further evaluation for these factors and their effect on CCA incidence and outcomes in those specific groups. [Table: see text]

e16059 Background: Anal cancer is an uncommon malignancy accounting for less than 3% of gastrointestinal malignancies in the US. In this large database study, we aimed to re-evaluate the difference in the incidence and mortality trend in both genders. Methods: We used SEER 18 database to study anal cancer cases in the US during 2000-2016. Incidence and mortality rates of anal cancer were calculated by gender and were expressed by 1,000,000 person-years. Annual percent change (APC) was calculated using join point regression software. Results: We reviewed 25,418 patients with anal cancer, of which 61.4% were females. Incidence of anal cancers was 14.375 and 19.427 per 1,000,000 person-years, in males and females, respectively. Incidence rates of anal cancer significantly increased over the study period, but this increase was sharper in females (APC = 2.220%, 95%CI [1.924-2.517], P < .001) when compared to males (APC = 0.915%, 95%CI [0.303-1.531], P = .006). Mortality rates from anal cancer over the study period were 7.425 and 7.532 per 1,000,000 person-years, in males and females, respectively. Overall anal cancer mortality rates did not change between 2000-2009 but started to decrease starting from 2010 and this decrease became sharpest between 2014-2016; APC = -44.905%, 95%CI [-57.572- -28.457], P = .001). Mortality rates followed the same trend in both genders. Conclusions: Anal cancer incidence is increasing with significant increase in the incidence trend is noticed in females compared to males which is a change from the previous trend that was seen from 1973-2000. On the other hand, anal cancer mortality has started to decrease for the first time starting from 2010 with no difference in the mortality trend between males and females. This improvement in mortality rate can be explained by the improvement in early detection rate and possibly improvement in the treatment approach for these high-risk patients.