Sequence of Contact X-ray Brachytherapy (CXB) and External Beam Radiation (EBRT) in organ-preserving treatment for small rectal cancer.

BACKGROUND AND PURPOSE: External Beam Radiotherapy (EBRT) followed by Contact X-ray Brachytherapy (CXB) and vice versa are viable alternatives to surgery for selected rectal cancer patients who have small tumours (≤3 cm). However, the optimal sequence of treatment needs to be established. We compared two approaches using Propensity Score (PS) matching and inverse probability treatment weighting (IPTW) analyses to investigate whether the sequence of treatment affected patient outcomes. MATERIALS AND METHODS: This retrospective analysis (2008-2019) included patients with rectal adenocarcinoma (cT1-3,N0-1,M0, grade 1-2, size ≤ 3 cm) who received both EBRT and CXB, irrespective of treatment sequence. PS matching and IPTW were conducted to balance covariate standardised mean differences between groups. Oncological outcomes and rate of post-treatment rectal bleeding were assessed. RESULTS: Following PS matching and IPTW analyses from 251 eligible patients; 103 starting with EBRT (median follow-up: 37 [IQR:18-56] months) and 148 with CXB (median follow-up: 32 [IQR:16-54] months, a significant improvement in 3-year overall survival (77% vs 85%, p = 0.02, [HR:0.58 (95% CI:0.37-0.91)]) and a higher risk of post-treatment rectal bleeding (grade 1 (26%) and grade 2 (6%)) were found in patients who started with CXB (p = 0.08). No significant differences were observed in local regrowth (18% vs 12%, p = 0.47), distant relapse (10% vs 6%, p = 0.53), 3-year organ preservation rates (70% vs 75%, p = 0.20, [HR:0.66 (95% CI: 0.35-1.26)]), or disease-free survival (78% vs 82%, p = 0.17, [HR: 0.47 (95% CI: 0.16-1.38)]) CONCLUSION: In patients with rectal cancer (≤3 cm), commencing with CXB rather than EBRT, was associated with improved overall survival, but had a higher risk of G1/2 rectal bleeding. No statistically significant differences were observed in other oncological outcomes.

HLA mismatch is important for 20-year graft survival in kidney transplant patients.

BACKGROUND: Human leukocyte antigens (HLA) matching is gradually being omitted from clinical practice in evaluation for renal allograft transplant. While such practices may yield shorter wait times and adequate short-term outcomes, graft longevity in HLA mismatched patients remains unclear. This study aims to demonstrate that HLA matching may still play an important role in long-term graft survival. METHODS: We identified patients undergoing an index kidney transplant in the United Network for Organ Sharing (UNOS) data from 1990 to 1999, with one-year graft survival. The primary outcome of the analysis was graft survival beyond 10 years. We explored the long-lasting impact of HLA mismatches by landmarking the analysis at established time points. RESULTS: We identified 76,530 patients receiving renal transplants in the time frame, 23,914 from living donors and 52,616 from deceased donors. On multivariate analysis, more HLA mismatches were associated with worse graft survival beyond 10 years for both living and deceased donor allografts. HLA mismatch continued to remain an essential factor in the long term. CONCLUSIONS: A greater number of HLA mismatches was associated with progressively worse long-term graft survival for patients. Our analysis reinforces the importance of HLA matching in the preoperative evaluation of renal allografts.

Outcomes after anti-thymocyte globulin vs Basiliximab induction before deceased donor kidney transplants.

BACKGROUND: Deceased donor kidney transplants represent an important source of renal replacement for the 100 000 patients initiating hemodialysis annually. We compared the association of induction therapy, anti-thymocyte globulin [rabbit] (rATG) or basiliximab, with posttransplant rejection, graft and patient survival. METHODS: Using the United Network for Organ Sharing (UNOS) database, we identified patients that received deceased donor kidney transplants. The outcomes analyzed were 6- month rejection, 1-year rejection, patient survival and graft survival. Multivariate logistic regression models were constructed to understand the association of induction therapy and rejection. Cox-proportional hazards models were constructed to ascertain the association of choice of induction therapy with both patient and graft survival. RESULTS: Of 45 339 patients, 33 906 patients received rATG induction therapy and 11 433 patients received basiliximab induction therapy. The rATG group were younger (53.44 years vs 55.28 years, P < 0.001), more frequently female (58.74% male vs 66.08%, P < 0.001) and more frequently Black (34.78% vs 25.66%, p < 0.001) compared with patients in the basiliximab group. Rejection was more likely with basiliximab compared with rATG at 6 months(OR = 1.64, P < 0.001; 7.81% Basiliximab vs 5.23% rATG)and at 12 months (OR = 1.56, P < 0.001; 8.81% Basiliximab vs 6.31% rATG). Basiliximab induction therapy was associated with worse patient survival, (HR = 1.05, P = 0.017). Basiliximab induction therapy was associated with worse graft survival, (HR = 1.03, P = 0.037). CONCLUSION: The analysis of the national experience demonstrated favorable rejection, patient survival, and graft survival with rATG usage. Further prospective data are necessary to provide treatment recommendations.