Capecitabine and Radiotherapy as Neoadjuvant Treatment for Rectal Cancer

Chemoradiation for muscle-invasive bladder cancer using 5-fluorouracil versus capecitabine: A nationwide cohort study

BACKGROUND AND PURPOSE

Oral capecitabine and intravenous 5-fluorouracil (5-FU) are both used as a radiosensitizer in chemoradiotherapy (CRT). A capecitabine-based regimen is more convenient for both patients and healthcare professionals. Since large comparative studies are lacking, we compared toxicity, overall survival (OS) and disease-free survival (DFS) between both CRT-regimens in patients with muscle-invasive bladder cancer (MIBC).

MATERIALS AND METHODS

All patients diagnosed with non-metastatic MIBC between November 2017-November 2019 were consecutively included in the BlaZIB study. Data on patient, tumor, treatment characteristics and toxicity were prospectively collected from the medical files. From this cohort, all patients with cT2-4aN0-2/xM0/x, treated with capecitabine or 5-FU-based CRT were included in the current study. Toxicity in both groups was compared using Fisher-exact tests. Propensity score-based inverse probability treatment weighting (IPTW) was applied to correct for baseline differences between groups. IPTW-adjusted Kaplan-Meier OS and DFS curves were compared using log-rank tests.

RESULTS

Of the 222 included patients, 111 (50%) were treated with 5-FU and 111 (50%) with capecitabine. Curative CRT was completed according to treatment plan in 77% of patients in the capecitabine-based group and 62% of the 5-FU group (p = 0.06). Adverse events (14 vs 21%, p = 0.29), 2-year OS (73% vs 61%, p = 0.07) and 2-year DFS (56% vs 50%, p = 0.50) did not differ significantly between groups.

CONCLUSIONS

Chemoradiotherapy with capecitabine and MMC is associated with a similar toxicity profile compared to 5-FU plus MMC and no difference in survival was found. Capecitabine-based CRT, as a more patient-friendly schedule, may be considered as an alternative to a 5-FU-based regimen.

The efficacy of adding targeted agents to neoadjuvant therapy for locally advanced rectal cancer patients: a meta-analysis

Patients with locally advanced rectal cancer (LARC) are at tremendous risk of metastatic diseases. To improve the prognoses of LARC patients, the efficacy of adding targeted agents to neoadjuvant therapy has been investigated by many researchers but remains controversial. A literature search of relevant databases was conducted through December 2016, 804 studies were identified and 32 investigations were ultimately included. A total of 1196 patients from 31 cohorts of 29 studies were eligible for quantitative synthesis in this single‐arm setting meta‐analysis. As pathologic complete response (pCR) shows promise as a prognosis indicator, we focused on pCR rates to evaluate whether adding targeted agents to neoadjuvant therapies improves the outcome of LARC patients. In our study, we revealed pooled estimates of pCR of 27% (95%CI, 21–34%) and 14% (95%CI, 9–21%) for bevacizumab‐relevant cohorts and cetuximab‐relevant cohorts, respectively. The safety of adding targeted agents to neoadjuvant therapy was also evaluated by pooling the data of Grade 3/4 toxicity. In conclusion, our study revealed that adding bevacizumab to the neoadjuvant therapy regimens provides appreciable pCR for LARC patients. Meanwhile, the efficacy of cetuximab remains inconclusive, RCTs with larger scale and better study design that stress more on mutational status are needed.

Neoadjuvant capecitabine, bevacizumab and radiotherapy for locally advanced rectal cancer: results of a single-institute Phase I study

The aim of this Phase I clinical trial was to assess the feasibility and safety of capecitabine-based preoperative chemoradiotherapy (CRT) combined with bevacizumab and to determine the optimal capecitabine dose for Japanese patients with locally advanced rectal cancer. Patients with cT3/T4 rectal cancer were eligible. Bevacizumab was administered at 5 mg/kg intravenously on Days 1, 15 and 29. Capecitabine was administered on weekdays concurrently with pelvic radiotherapy at a daily dose of 1.8 Gy, totally to 50.4 Gy. Capecitabine was initiated at 825 mg/m(2) twice daily at Dose Level 1, with a planned escalation to 900 mg/m(2) twice daily at Dose Level 2. Within 6.1-10.3 (median, 9.4) weeks after the completion of the CRT, surgery was performed. Three patients were enrolled at each dose level. Regarding the CRT-related acute toxicities, all of the adverse events were limited to Grade 1. There was no Grade 2 or greater toxicity. No patient needed attenuation or interruption of bevacizumab, capecitabine or radiation. All of the patients received the scheduled dose of CRT. All of the patients underwent R0 resection. Two (33.3%) of the six patients had a pathological complete response, and five (83.3%) patients experienced downstaging. In total, three patients (50%) developed postoperative complications. One patient developed an intrapelvic abscess and healed with incisional drainage. The other two patients healed following conservative treatment. This regimen was safely performed as preoperative CRT for Japanese patients with locally advanced rectal cancer. The recommended capecitabine dose is 900 mg/m(2) twice daily.

The role of capecitabine in locally advanced rectal cancer treatment: an update

Preoperative infusional 5-fluorouracil (5-FU) and concurrent radiation therapy (RT) followed by total mesorectal surgery is the current standard of care for locally advanced rectal cancer (LAR). When compared with postoperative 5-FU-based chemoradiation, this strategy is associated with significantly lower rates of local relapse, lower toxicity and better compliance. Capecitabine is a rationally designed oral prodrug that is converted into 5-FU by intracellular thymidine phosphorylase. Substitution of infusional 5-FU with capecitabine is an attractive option that provides a more convenient administration schedule and, possibly, increased efficacy. Indeed, incorporation of capecitabine in combined modality neoadjuvant therapy for LAR has been under intense investigation during the last 10 years. Phase I and II clinical trials showed that a regimen consisting of capecitabine 825mg/m(2) twice daily for 7 days/week continuous oral administration in combination with RT is an active and well tolerated regimen, thereby being the preferred concurrent regimen. The definitive demonstration that efficacy of capecitabine/RT is similar to 5-FU/RT has been provided by the NSABP-R-04 and the German Margit trials. One approach to improve outcomes in rectal cancer is to deliver a second RT-sensitizing drug with effective systemic activity. Oxaliplatin and irinotecan are therefore good candidates. However, two phase III trials demonstrated that incorporation of oxaliplatin to capecitabine with RT did not improve early outcomes and, by contrast, increased toxicity. Capecitabine has also been combined with irinotecan. This regimen showed encouraging results in phase I and II clinical trials, which led to an ongoing phase III clinical trial. New strategies with induction chemotherapy with or without chemoradiation prior to surgery are currently under investigation. Whether or not capecitabine has a role in this setting is being investigated in ongoing trials. Incorporation of agents directed towards new targets, such as anti-epidermal growth factor receptor (EGFR) antibodies or antiangiogenic agents, in combination preoperative regimens, is being hampered by results of early trials in which efficacy outcomes with cetuximab were poor and an excessive rate of surgical complications with bevacizumab was observed. The lack of improvements in efficacy with the addition of cetuximab or bevacizumab in the adjuvant treatment of colon cancer led to concerns about further development of these agents in rectal cancer. The role of capecitabine in the postoperative adjuvant setting is the aim of the ongoing Dutch SCRIPT trial. The prediction of response associated with capecitabine has been based on expression of thymidylate synthase and dihydropyrimidine dehydrogenase, as well as on gene expression arrays. All these procedures require further validation and should be considered as investigational. In conclusion, capecitabine can safely and effectively replace intravenous continuous infusion of 5-FU in the preoperative chemoradiation setting for rectal cancer management. The addition of other new antineoplastic agents to a fluoropyrimidine-based regimen remains investigational.

A phase II study of neoadjuvant bevacizumab plus capecitabine and concomitant radiotherapy in patients with locally advanced rectal cancer

PURPOSE

To assess safety and activity of neoadjuvant bevacizumab, capecitabine and standard radiotherapy in locally advanced rectal cancer as well as potential predictive biomarkers.

PATIENTS AND METHODS

The multicentric phase II study enrolled 43 patients who received bevacizumab infusion (5 mg/kg) every 2 weeks for 4 cycles; oral capecitabine at 825 mg/m(2) twice a day for 5.5 weeks with external-beam irradiation (50.4 Gy in 28 fractions over 5.5 weeks). We determined certain biomarkers before and after therapy for correlation with response.

RESULTS

Post-operative histologic examination revealed no residual cancer cells in 6 of the 43 patients (14%; 95% confidence limits 3.60-24.31%). In another 22 patients (51.2%) a varying percentage of cancer cells in residual areas of fibrosis/ necrosis was found, corresponding to Mandard TRG 2 or 3 classification. Tumor resection with negative circumferential margin was achieved in 38/40 (95%) operated patients. Sphincter-sparing surgery was obtained in 31 (72.1%) patients. Primary tumor and lymph nodes downstaging was observed in 15 (34.9%) and 16 (37.2%) cases, respectively. Neoadjuvant therapy was safe and well tolerated. The most frequent side effects were G1-2 diarrhea, proctitis, rectal bleeding and hypertension. No biomarker tested was significantly predictive of both pathological complete response and disease-free survival. Pre-treatment CD-34 vessel density, post-treatment Ki-67 labeling index and VEGFR-2 cancer cells expression significantly correlated with residual tumor area.

CONCLUSIONS

The schedule of neoadjuvant therapy tested was safe and active. Pre-treatment vessel density by the panendothelial marker anti CD-34 antibody, post-treatment Ki-67 labeling index and VEGFR-2 expression were significantly associated to residual tumor area. The biomarkers correlations warrant further evaluation in prospective clinical trials.

Re-irradiation combined with capecitabine in locally recurrent squamous cell carcinoma of the head and neck. A prospective phase II trial

BACKGROUND

We performed a prospective phase II trial to investigate the safety and efficacy of radiotherapy combined with capecitabine in patients suffering from a recurrence of a squamous cell carcinoma of the head and neck (SCCHN) within a previously irradiated field.

PATIENTS AND METHODS

A total of 31 evaluable patients with recurrent SCCHN received re-irradiation with a total dose of 50 Gy (25 fractions over 5 weeks) up to a maximum of 60 Gy combined with 900 mg/m(2)/day capecitabine given on the days of radiotherapy.

RESULTS

The median time to relapse after the first course of radiotherapy was 15 months. The overall response rate in our study was 68% including 6 patients with a complete response. The median overall survival was 8.4 months. Grade 3 or 4 mucositis occurred in 4 patients and 1 patient, respectively. No grade 4 hematological toxicities were observed; 1 patient had grade 3 anemia. The cumulative median lifetime dose was 116 Gy.

CONCLUSION

Capecitabine combined with re-irradiation is a well-tolerated treatment in patients with recurrent SCCHN. In light of its good tolerability, it appears to be a potential option for patients with a reduced performance status and may also serve as a basis for novel treatment concepts, such as in combination with targeted therapies.

Preoperative intensified radiochemotherapy for rectal cancer: experience of a single institution

PURPOSE

The aim of our study was to evaluate the feasibility and the effectiveness of an intensified neoadjuvant protocol with the addition of weekly oxaliplatin in the preoperative strategy of rectal cancer treatment.

PATIENTS AND METHODS

Patients with locally advanced rectal cancer received continous infusion 5-Fluorouracil (5-FU) 200 mg/m(2)/day in combination with weekly oxaliplatin at a dose of 50 mg/m(2). Doses of radiotherapy were 45 Gy to the whole pelvis plus 5.4-9 Gy to the tumour mass. The primary end-points of the study were evaluation of toxicity, compliance with radiotherapy and chemotherapy, downstaging, pathological complete response (pCR) and the rate of sphincter preservation for distal cancers. Secondary end-points were relapse-free and overall survival.

RESULTS

From November 2006 to June 2009, 51 patients were enrolled into the study. Compliance with chemotherapy was 80%. The incidence of G3 diarrhoea and proctitis were 17.6% and 21.5%, respectively. Surgery was performed in 48 patients with 100% R0 resection. 76.4% of low-lying tumours underwent conservative treatment. Seventy-nine percent of patients were downstaged: T and N downstaging were observed in 71% and 75% of patients, respectively. A pCR was obtained in 11 (22.9%) patients.

CONCLUSIONS

Intensification of neoadjuvant treatment for rectal cancer with the addition of weekly oxaliplatin is feasible, with remarkable rates of downstaging and pathological complete response. Data on sphincter preservation for distal cancers were excellent. Phase III trials with a longer follow-up will establish whether this good outcome in terms of surrogate end-points will translate into better rates of disease-free and overall survival.

(188)Re-HEDP combined with capecitabine in hormone-refractory prostate cancer patients with bone metastases: a phase I safety and toxicity study

Purpose

¹⁸⁸Re-HEDP is indicated for the treatment of pain in patients with painful osteoblastic bone metastases, including hormone-refractory prostate cancer patients. Efficacy may be improved by adding chemotherapy to the treatment regimen as a radiation sensitizer. The combination of ¹⁸⁸Re-HEDP and capecitabine (Xeloda®) was tested in a clinical phase I study.

Methods

Patients with hormone-refractory prostate cancer were treated with capecitabine for 14 days (oral twice daily in a dose escalation regimen with steps of 1/3 of 2,500 mg/m² per day in cohorts of three to six patients, depending on toxicity). Two days later patients were treated with 37 MBq/kg ¹⁸⁸Re-HEDP as an intravenous injection. Six hours after treatment post-therapy scintigraphy was performed. Urine was collected for 8 h post-injection. Follow-up was at least 8 weeks. The primary end-point was to establish the maximum tolerable dose (MTD) of capecitabine when combined with ¹⁸⁸Re-HEDP. Secondary end-points included the effect of capecitabine on the biodistribution and pharmacokinetics of ¹⁸⁸Re-HEDP.

Results

Three patients were treated in the first and second cohorts, each without unacceptable toxicity. One of six patients in the highest cohort experienced unacceptable toxicity (grade 4 thrombopaenia). The MTD proved to be the maximum dose of 2,500 mg/m² per day capecitabine. No unexpected toxicity occurred. Capecitabine had no effect on uptake or excretion of ¹⁸⁸Re-HEDP.

Conclusion

Capecitabine may be safely used in combination with ¹⁸⁸Re-HEDP in a dose of 2,500 mg/m² per day and 37 MBq/kg, respectively. Efficacy will be further studied in a phase II study using these dosages.

Participation of DNA repair in the response to 5-fluorouracil

The anti-metabolite 5-fluorouracil (5-FU) is employed clinically to manage solid tumors including colorectal and breast cancer. Intracellular metabolites of 5-FU can exert cytotoxic effects via inhibition of thymidylate synthetase, or through incorporation into RNA and DNA, events that ultimately activate apoptosis. In this review, we cover the current data implicating DNA repair processes in cellular responsiveness to 5-FU treatment. Evidence points to roles for base excision repair (BER) and mismatch repair (MMR). However, mechanistic details remain unexplained, and other pathways have not been exhaustively interrogated. Homologous recombination is of particular interest, because it resolves unrepaired DNA intermediates not properly dealt with by BER or MMR. Furthermore, crosstalk among DNA repair pathways and S-phase checkpoint signaling has not been examined. Ongoing efforts aim to design approaches and reagents that (i) approximate repair capacity and (ii) mediate strategic regulation of DNA repair in order to improve the efficacy of current anticancer treatments.

Neo-adjuvant treatment of rectal cancer with capecitabine and oxaliplatin in combination with radiotherapy: a phase II study

BACKGROUND

Preoperative chemoradiation is now standard treatment for stages II-III rectal cancer. Capecitabine (CAP) and oxaliplatin (OX) are synergistic with radiotherapy (RT) and active in colorectal neoplasms.

PATIENTS AND METHODS

Two cycles of CAP 825 mg/m(2) b.i.d. (days 1-14) and OX 50 mg/m(2) (days 1 and 8) every 3 weeks were given concomitantly with pelvic conformal RT (45 Gy). Patients with a > or =T3 and/or node-positive rectal tumour were eligible. The pathologic tumour response was defined according to the tumour regression grade (TRG) scale.

RESULTS

Forty-six patients were enrolled. Gastrointestinal adverse events were mostly G1-G2; only two patients experienced G3 vomiting and diarrhoea and six patients had G1 peripheral neuropathy. Haematological toxicity was rare. G2 proctitis and anal pain occurred in two patients. Pathological complete response (TRG1) was observed in nine patients (20.9%; 95% CI 8.7%-33.1%); TRG2 in 19 patients (44.2%); TRG3 in 12 patients (27.9%); and TRG4 in three patients (7%). Overall, nine patients recurred: five with distant metastases, one with local recurrence, and three with both local recurrence and distant metastases.

CONCLUSIONS

CAP-OX-RT as preoperative treatment for rectal cancer induces a remarkable rate of complete or near-complete pathologically documented response and is well tolerated.