The value of post-operative chemotherapy after chemoradiotherapy in patients with high-risk locally advanced rectal cancer-results from the RAPIDO trial

BACKGROUND

Pre-operative chemoradiotherapy (CRT) rather than radiotherapy (RT) has resulted in fewer locoregional recurrences (LRRs), but no decrease in distant metastasis (DM) rate for patients with locally advanced rectal cancer (LARC). In many countries, patients receive post-operative chemotherapy (pCT) to improve oncological outcomes. We investigated the value of pCT after pre-operative CRT in the RAPIDO trial.

PATIENTS AND METHODS

Patients were randomised between experimental (short-course RT, chemotherapy and surgery) and standard-of-care treatment (CRT, surgery and pCT depending on hospital policy). In this substudy, we compared curatively resected patients from the standard-of-care group who received pCT (pCT+ group) with those who did not (pCT- group). Subsequently, patients from the pCT+ group who received at least 75% of the prescribed chemotherapy cycles (pCT ≥75% group) were compared with patients who did not receive pCT (pCT-/- group). By propensity score stratification (PSS), we adjusted for the following unbalanced confounders: age, clinical extramural vascular invasion, distance to the anal verge, ypT stage, ypN stage, residual tumour, serious adverse event (SAE) and/or readmission within 6 weeks after surgery and SAE related to pre-operative CRT. Cumulative probability of disease-free survival (DFS), DM, LRR and overall survival (OS) was analysed by Cox regression.

RESULTS

In total, 396/452 patients had a curative resection. The number of patients in the pCT+, pCT >75%, pCT- and pCT-/- groups was 184, 112, 154 and 149, respectively. The PSS-adjusted analyses for all endpoints demonstrated hazard ratios between approximately 0.7 and 0.8 (pCT+ versus pCT-), and 0.5 and 0.8 (pCT ≥75% versus pCT-/-). However, all 95% confidence intervals included 1.

CONCLUSIONS

These data suggest a benefit of pCT after pre-operative CRT for patients with high-risk LARC, with approximately 20%-25% improvement in DFS and OS and 20%-25% risk reductions in DM and LRR. Compliance with pCT additionally reduces or improves all endpoints by 10%-20%. However, differences are not statistically significant.

Brain lesions in a patient with rectal cancer: mind your step

Cerebral toxoplasmosis is a potentially fatal infection most commonly seen in immunocompromised patients. We present a patient on long-term immunosuppressive therapy after kidney transplantation and a recent history of oligometastatic rectal cancer, with cerebral lesions as a result of toxoplasmosis. Heightened awareness of the occurrence of opportunistic infections in patients with cancer who are taking immunosuppressive drugs is needed among clinicians.

Abstract S6-02: The efficacy and safety of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone-receptor positive early breast cancer. First results of the TEAM IIB trial (BOOG 2006-04)

Background:

Results of clinical trials concerning adjuvant bisphosphonates for the prevention of (bone) metastases in patients with early breast cancer are conflicting. A recent large meta-analysis, however, suggests that bisphosphonates reduce the incidence of (bone) metastases and improve skeletal-related events in early breast cancer patients. Subgroup analyses show that postmenopausal women seem to benefit the most. In this subgroup a modest overall survival benefit was observed with the addition of adjuvant bisphosphonates to standard adjuvant systemic therapy (EBCTCG, Lancet, 2015). TEAM IIB, a randomized phase III study (ISRCTN17633610), prospectively investigates the value of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone receptor-positive breast cancer.

Methods:

Postmenopausal women with stage I-III breast cancer and an indication for adjuvant hormonal treatment were randomized to receive at least 5 years of hormonal therapy (tamoxifen followed by at least 2-3 years exemestane, or in case of high risk at least 5 years of exemestane) with or without ibandronate 50mg orally, once daily for three years. Primary endpoint was disease-free survival (DFS). Secondary endpoints included time to and rate of bone metastases, other sites of recurrence, overall survival and safety. The study was amended because of slower than anticipated accrual and the sample size calculations were amended accordingly in June 2009. To detect a hazard ratio (HR) of 0.615 with a 2-sided alpha of 0.05 and a power of 0.8, 139 DFS-events were required in the intention-to-treat population.

Results: Between February 2007 and May 2014, 1116 patients were enrolled in 37 hospitals in the Netherlands of whom 40% had positive axillary lymph nodes and 56% of all patients received (neo)adjuvant chemotherapy (>95% anthracyclines, 69% taxanes). Baseline characteristics were well balanced. At September 9, 2016, 143 DFS events had been reported. Median follow-up was 4.6 years and 80 patients were still on ibandronate treatment. Adherence to 3 years ibandronate was 67%, 21 patients randomized to receive ibandronate never started. 19 patients, of whom 9 in the control group were excluded because of major ineligibility.

In the ibandronate treated group 3-year DFS was 94.4% versus 90.8% in the control group (HR 0.84; 95% confidence interval [CI] 0.60-1.17). In total, 48 patients in the ibandronate versus 45 in the control group died, of whom 18 (37,5%) versus 28 (62,2%) of breast cancer. 3 years after randomization 1.6% of ibandronate treated patients developed bone metastases versus 4.6% in patients who were treated with adjuvant hormonal therapy only (HR 0.76; [CI] 0.43-1.32). 14 (29,2%) versus 9 (20%) of patients died because of secondary malignancies respectively.

There was no significant difference in creatinine clearance during the first three years after randomization. 36 Serious adverse events (SAEs) were reported in the ibandronate group versus 51 in the control group. Of patients randomized to ibandronate 4 developed osteonecrosis, but without residual complaints.

Conclusion: So far, at a median follow-up of 4.6 years there is no statistically significant benefit from adding ibandronate to adjuvant hormonal treatment in postmenopausal women with hormone-receptor positive early breast cancer. However, since hazard rates are in favor of ibandronate longer follow-up is warranted before final conclusions can be drawn.

Citation Format: Vliek SB, Meershoek-Klein Kranenbarg E, van Rossum AGJ, Tanis BC, Putter H, van der Velden AWG, Hendriks MP, van Bochove A, van Riet Y, van Leeuwen-Stok AE, Tjan-Heijnen VCG, Kroep JR, Nortier JWR, van de Velde CJH, Linn SC. The efficacy and safety of the addition of ibandronate to adjuvant hormonal therapy in postmenopausal women with hormone-receptor positive early breast cancer. First results of the TEAM IIB trial (BOOG 2006-04) [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr S6-02.

Encapsulating peritoneal sclerosis in patients on peritoneal dialysis

Encapsulating peritoneal sclerosis (EPS) is an uncommon but one of the most serious complications in patients on long-term peritoneal dialysis. EPS is characterised by a diffuse thickening and/or sclerosis of the peritoneal membrane which leads to a decreased ultrafiltration and ultimately to bowel obstruction. We present four cases of EPS and discuss the clinical manifestations, multifactorial aetiology, diagnosis, treatment, prognosis, and prevention. We end with a proposal for the development of an EPS prevention guideline.

Cyclosporine short infusion and C2 monitoring in haematopoietic stem cell transplant recipients

Blood concentrations of cyclosporine A (CsA) >or=800 microg/l measured 2 h post-dosing, the C2 concentration, is necessary to obtain a maximal pharmacological effect and correlates well with transplant-related complications such as transplant rejection and toxicity. In an open crossover study CsA blood levels were measured during 24 h to generate a pharmacokinetic profile on days 1, 8 and 15 after starting CsA infusion in 21 haematopoietic allogeneic stem cell transplant recipients who were receiving intravenously CsA 3 mg/kg/day either by continuous infusion or by 2 h infusion given every 12 h. C2 levels after the 2 h infusion correlated better than C1 or C3 levels with the area under the concentration-time curve from 0 to 4 h (r2=0.62). C2 levels >or=800 microg/l were also achieved for 20 out of 24 (83%) of cases after the 2 h infusion of CsA without any increase of CsA-related toxicity but for only three of the 23 patients (13%) after continuous infusion. Therefore, we recommend CsA infusions in 2 h during transplant and perform C2 monitoring to obtain therapeutic C2 levels >or=800 microg/l.