Background: Perforation is a serious life-threatening complication of lymphomas involving the gastrointestinal (GI) tract.Although some perforations occur as the initial presentation of GI lymphoma, others occur after initiation of chemotherapy. To define the location and timing of perforation, a single-center study was carried out of all patients with GI lymphoma. Patients and methods:Between 1975 and 2012, 1062 patients were identified with biopsy-proven GI involvement with lymphoma. A retrospective chart review was undertaken to identify patients with gut perforation and to determine their clinicopathologic features.Results: Nine percent (92 of 1062) of patients developed a perforation, of which 55% (51 of 92) occurred after chemotherapy. The median day of perforation after initiation of chemotherapy was 46 days (mean, 83 days; range, 2-298) and 44% of perforations occurred within the first 4 weeks of treatment. Diffuse large B-cell lymphoma (DLBCL) was the most common lymphoma associated with perforation (59%, 55 of 92). Compared with indolent B-cell lymphomas, the risk of perforation was higher with aggressive B-cell lymphomas (hazard ratio, HR = 6.31, P < 0.0001) or T-cell/other types (HR = 12.40, P < 0.0001). The small intestine was the most common site of perforation (59%). Conclusion:Perforation remains a significant complication of GI lymphomas and is more frequently associated with aggressive than indolent lymphomas. Supported in part by University of Iowa/Mayo Clinic SPORE CA97274 and the Predolin Foundation.

Summary:Absolute lymphocyte count at day 15 (ALC-15) after autologous peripheral blood hematopoietic stem cell transplantation (APHSCT) is an independent prognostic factor for survival in non-Hodgkin's lymphoma (NHL). Factors affecting ALC-15 remain unknown. We hypothesized that dose of infused autograft lymphocytes (A-ALC) directly impacts upon ALC-15. A total of 190 consecutive NHL patients received A-ALC between 1993 and 2001. The primary end point was correlation between A-ALC and ALC-15. A strong correlation was identified (r ¼ 0.71). A higher A-ALC was infused into patients achieving an ALC-15 X500/ll vs ALC-15 o500/ll (median of 0.68 Â 10 9 /kg (0.04-2.21 Â 10 9 /kg), vs 0.34 Â 10 9 /kg (0.04-1.42 Â 10 9 /kg), Po0.0001). The median follow-up for all patients was 36 months (maximum of 109 months). The A-ALC threshold was determined at 0.5 Â 10 9 /kg. The median overall survival (OS) and progression-free survival (PFS) times were longer in patients who received an A-ALC X0.5 Â 10 9 /kg vs A-ALC o0.5 Â 10 9 /kg (76 vs 17 months, Po0.0001; 49 vs 10 months, Po0.0001, respectively). Multivariate analysis demonstrated A-ALC to be an independent prognostic indicator for OS and PFS. These data support our hypothesis that ALC-15 and survival are dependent upon the dose of infused A-ALC in NHL.

8526 Background: Many randomised trials have evaluated the role of adjuvant interferon-a (IFN) in high-risk melanoma, some suggesting benefit and others not. To assess the totality of current evidence, an individual patient data (IPD) meta-analysis of all available trials was performed. Methods: Standard IPD meta-analysis methods were used to assess event-free (EFS) and overall survival (OS), with odds ratios (OR) and 95% confidence intervals (CI) calculated. Trials were divided by dose of IFN - high (20 MU/m2), intermediate (5–10 MU), low (3 MU) and very low (1 MU). Subgroup analyses by patient age, gender and disease characteristics were also performed. Results: IPD was provided for 10 of 13 reported trials of IFN vs. no IFN (for the other 3 trials published data were used). 6067 patients (IPD available for 85%) were included in the analysis, with over 3,700 and 3,000 events for EFS and OS. There was statistically significant benefit for IFN for both EFS (OR=0.87, CI=0.81–0.93, p=0.00006) and OS (0.9, 0.84–0.97, p=0.008). There was no evidence of differences according to dose (Table 1; trend p>0.1) or duration of IFN. This proportional survival advantage translates into an absolute benefit of about 3% (CI 1%-5%) at 5 years. The effect of IFN did not differ with age, gender, tumor site, Breslow thickness, clinical nodes or disease stage. Only for ulceration was there some evidence of an interaction (p=0.03); patients with ulcerated tumors had greater benefit from IFN (EFS: OR=0.76, OS: OR=0.77) than those with no ulceration (EFS: OR=0.94, OS: OR=0.98). Conclusions: This meta-analysis provides evidence that adjuvant IFN significantly reduces the risk of relapse and improves overall survival, although the absolute survival benefit is relatively small. This analysis does not however, clarify the optimal (high, intermediate or low) dose of IFN. Given the large number of subgroup analyses performed, the apparent increased benefit in patients with ulceration requires confirmation. No significant financial relationships to disclose.