Efficacy of second-line chemotherapy after a first-line triplet in patients with metastatic colorectal cancer

Effect of oxaliplatin-based chemotherapy on chemosensitivity in patients with peritoneal metastasis from colorectal cancer treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy: proof-of-concept study

Background

Chemosensitivity testing, including collagen gel droplet‐embedded culture drug sensitivity test, has proven to be a useful tool in therapeutic decision‐making. This retrospective analysis investigated chemosensitivity testing of peritoneal metastases collected during cytoreductive surgery (CRS), and its impact on survival in patients with colorectal cancer.

Methods

All patients with peritoneal metastasis from colorectal cancer who underwent CRS with or without hyperthermic intraperitoneal chemotherapy (HIPEC) between November 2008 and October 2014 were included. The growth inhibition rate was expressed as the ratio between the image density after treatment (T) and that before treatment (control, C). Tumours with a reduction in T/C ratio of less than 20 per cent were defined as resistant and those with a reduction of 20 per cent or more as sensitive. Groups were compared for overall (OS) and disease‐free (DFS) survival.

Results

Of 84 eligible patients, 81 received neoadjuvant chemotherapy (NACT), including 56 patients with an oxaliplatin‐based regimen. Mean(s.d.) follow‐up was 23·4(22·9) months. The median overall survival of all patients was 19·0 (i.q.r. 5·7–36·1) months, with a progression‐free survival time of 10·1 (4·5–17·0) months. Patients who received oxaliplatin‐based NACT had significantly altered chemosensitivity to oxaliplatin; only 20 of 51 such patients showed chemosensitivity to oxaliplatin compared with 16 of 24 who did not undergo oxaliplatin‐based NACT (P = 0·046). However, patients who showed chemoresistance to oxaliplatin had similar OS to those with chemosensitivity (18·8 versus 18·1 months; P = 0·835). The choice of HIPEC agents in patients who received oxaliplatin‐based NACT did not significantly influence survival (oxaliplatin versus mitomycin C: median OS 20·6 (10·9–24·8) versus 19·0 (10·5–34·6) months, P = 0·811; DFS 6·6 (2·8–25·7) versus 9·3 (4·1–13·9) months, P = 0·191).

Conclusion

Patients who had oxaliplatin‐based NACT showed a higher rate of chemoresistance to oxaliplatin at the time of CRS and HIPEC. The impact of chemosensitivity testing on OS remains unclear and needs further investigation.

An appraisal of emerging second line therapies for metastatic colorectal cancer

INTRODUCTION

Despite a significant improvement in overall survival over the last 15 years, colorectal cancer remains a major public health problem worldwide. Much effort has been made to develop an optimal choice of first-line treatments, but after progression the therapeutic possibilities and the criteria for choice are different.

AREAS COVERED

The purpose of this literature review is to discuss the different possibilities of second-line treatment and to specify the criteria for choice. Biological subgroups requiring specific therapeutic decisions will be described. We conducted a systematic review for randomized controlled trials published since 1995. A non-exhaustive review of published phase II studies, cohort studies, and international guidelines was also given and future leads were discussed.

EXPERT OPINION

Some choices of second-line treatments are a direct result of the option chosen in the first line. Others are necessary because of the biological specificity of the tumor: immunotherapy for tumors with microsatellite instability, or the combination encorafenib cetuximab for mutated BRAF-V600E tumors. In many other circumstances, there are several options that require extensive involvement of multidisciplinary boards and the patient in the final therapeutic decision.

Hepatic arterial infusion of oxaliplatin plus systemic chemotherapy and targeted therapy for unresectable colorectal liver metastases

BACKGROUND

Hepatic arterial infusion (HAI) combined with systemic chemotherapy has shown promising results in patients with unresectable colorectal liver metastases (CRLM), even after failure to systemic therapy. Addition of systemic targeted therapies has been investigated with controversial results regarding tolerance, especially with HAI-floruxidine when combined with systemic bevacizumab. Our study aimed to analyse feasibility, safety and efficacy of HAI-oxaliplatin plus systemic chemotherapy and targeted therapies.

METHODS

Between 2005 and 2016, single-centre consecutive patients with unresectable CRLM who received at least one cycle of HAI-oxaliplatin plus systemic chemotherapy and targeted therapies (cetuximab/panitumumab or bevacizumab) were analysed.

RESULTS

A total of 89 patients (median age 55 years (range, 26-76 years) who previously received a median number of one systemic chemotherapy regimen (range, 0-5) including oxaliplatin in 78% of cases were included. Median number of HAI-oxaliplatin cycles was 9 (range, 1-28) combined with systemic chemotherapy and targeted therapies (LV5FU2 [63%], FOLFIRI [36%]) plus anti-EGFR (30%), or bevacizumab (70%). Grade 3/4 toxicities included neutropenia (40%), HAI-related abdominal pain (43%) and neurotoxicity (12%). The intent-to-treat objective response rate was 42%, and 45% had stable disease, allowing complete CRLM resection/ablation in 27% of patients. After a median follow-up of 72 months, median overall and progression-free survival was 20 and 9 months, respectively.

CONCLUSION

Addition of targeted therapy to systemic chemotherapy combined with HAI-oxaliplatin is feasible, safe and shows promising activity, even after systemic chemotherapy failure.