Resection of non-hepatic colorectal cancer metastasis

Peri-operative chemotherapy for resectable colorectal lung metastasis: a systematic review and meta-analysis

Purpose

Several studies have evaluated surgical resection of pulmonary metastases as a standard treatment option for colorectal cancer (CRC) patients with resectable pulmonary metastases. However, the role of peri-operative chemotherapy after complete resection of pulmonary metastases from CRC patients is still controversial. This systematic review and meta-analysis is aimed to investigate the clinical efficacy of peri-operative chemotherapy after resection of CRC pulmonary metastases.

Methods

PubMed, the Cochrane Library databases, and Embase were searched for studies evaluating the effect of peri-operative chemotherapy on the survival of patients with CRC after pulmonary metastasectomy. The hazard ratio (HR) was used for analyzing overall survival (OS) and progression-free survival (PFS)/recurrence-free survival (RFS)/disease-free survival (DFS).

Results

Eight studies were included in the final analysis. The outcome showed that peri-operative chemotherapy had a significant favourable effect on OS (HR 0.83, 95% CI 0.75–0.92, p < 0.05) and PFS/RFS/DFS (HR 0.67, 95% CI 0.53–0.86, p < 0.05) in patients who received pulmonary metastasectomy. Multivariate analysis also validated this result (OS: HR 0.56, 95% CI 0.36–0.86, p < 0.05; PFS/RFS/DFS: HR 0.64, 95% CI 0.46–0.87, p < 0.05). There was a significant benefit in peri-operative group on OS and PFS/RFS/DFS in studies with R0 resection of pulmonary metastases (OS: HR 0.72, 95% CI 0.53–0.97, p < 0.05; PFS/RFS/DFS: HR 0.72, 95% CI 0.54–0.95, p < 0.05) and metachronous pulmonary metastases (OS: HR 0.40, 95% CI 0.22–0.75, p < 0.05; PFS/RFS/DFS: HR 0.67, 95% CI 0.49–0.92, p < 0.05).

Conclusion

Our meta-analysis demonstrated a significant difference in favor of peri-operative chemotherapy in CRC patients who underwent resection of pulmonary metastases. More clinical data and studies are needed to validate the findings of our study.

Electronic supplementary material

The online version of this article (10.1007/s00432-020-03142-9) contains supplementary material, which is available to authorized users.

[The role of lymphadenectomy for treatment of colorectal liver metastases with regional lymph nodes involvement]

Liver resection remains the method of choice for treatment of colorectal liver metastases with good long-term results. Regional lymph nodes involvement is significant negative prognostic factor. Moreover, it has been considered as a contraindication for liver resection for a long time. The role of lymphadenectomy remains controversial. Current state of this problem is reviewed in the article. Liver regional lymph nodes involvement takes place in 10-20% of cases. PET/CT is the most sensitive method of preoperative diagnosis. Involvement of liver regional lymph nodes is currently not absolute contraindication for liver resection. Routine lymphadenectomy does not make sense, and, perhaps, is justified only within scientific trials for more accurate disease staging. Indications for lymphadenectomy are suspicious changes of lymph nodes revealed by preoperative visualization methods or by intraoperative exploration. Modern chemotherapy regimens allow to reconsider the prognostic importance of liver regional lymph node metastases and to extend indications for liver resections.

Should anti-EGFR mAbs be discontinued for conversion surgery in untreated right-sided metastatic colorectal cancer? A systematic review and meta-analysis

Background

Previous studies have demonstrated that left-sided tumors have better prognoses than right-sided tumors in RAS wild-type mCRC (metastatic colorectal cancer) patients, while anti-EGFR mAbs appear to have no advantage compared with bevacizumab for right-sided tumors in these patients. Nevertheless, it remains unclear whether primary tumor location affects patients’ options for potentially curative resection.

Methods

PubMed, the Cochrane Library, Embase, ASCO, and ESMO conference abstracts were searched. The inclusion criteria were RCT (randomized controlled trials) studies that evaluated the efficacy of anti-EGFR mAbs based on primary tumor location. The outcomes included ORR, ETS, and DpR. ORs for ORR were calculated with 95% confidence intervals by Comprehensive Meta-Analysis, version 2.0.

Result

Nine studies including nine RCTs were analyzed. Regardless of left- or right-sided tumors, the ORRs for anti-EGFR mAb (left-sided: 80.2%, 95% CI, 47–95%; I² = 76.9%; right-sided: 46.1%, 95% CI, 39.4–53.0%; I² = 18.9%) were both higher than the control arm including chemotherapy with or without bevacizumab. The ORs for anti-EGFR mAbs have a significant benefit compared with chemotherapy with or without bevacizumab in left-sided tumors (OR = 2.19, 95% CI, 1.41–3.38; P < 0.001). For right-sided tumors, anti-EGFR mAbs still significantly improved the ORR compared with chemotherapy alone (OR = 1.75, 95% CI, 1.05–2.90; P = 0.03), and the OR numerically favored the anti-EGFR mAbs compared with bevacizumab (OR = 1.281, 95% CI, 0.77–2.12; P = 0.335). The data of ETS and DpR from three RCTs also favored the EGFR antibody irrespective of tumor location. Resection data on differentiating tumor locations is inconclusive. For right-sided tumors, it should be noted that median PFS and OS were comparable for patients who achieved ETS in both treatment arms.

Conclusions

Anti-EGFR mAbs have advantages in the tumor shrinkage regardless of left- or right-sided tumors, which is important for conversion therapy. For right-sided tumors, anti-EGFR mAbs should remain the first choice for potentially curative resection in RAS wild-type mCRC patients. ETS may represent a subgroup of patients with right-sided tumors who might benefit from the anti-EGFR mAb.

Electronic supplementary material

The online version of this article (10.1186/s12957-018-1502-7) contains supplementary material, which is available to authorized users.

Effects of Oxaliplatin Treatment on the Myenteric Plexus Innervation and Glia in the Murine Distal Colon

Oxaliplatin (platinum-based chemotherapeutic agent) is a first-line treatment of colorectal malignancies; its use associates with peripheral neuropathies and gastrointestinal side effects. These gastrointestinal dysfunctions might be due to toxic effects of oxaliplatin on the intestinal innervation and glia. Male Balb/c mice received intraperitoneal injections of sterile water or oxaliplatin (3 mg/kg/d) triweekly for 2 weeks. Colon tissues were collected for immunohistochemical assessment at day 14. The density of sensory, adrenergic, and cholinergic nerve fibers labeled with calcitonin gene-related peptide (CGRP), tyrosine hydroxylase (TH), and vesicular acetylcholine transporter (VAChT), respectively, was assessed within the myenteric plexus of the distal colon. The number and proportion of excitatory neurons immunoreactive (IR) against choline acetyltransferase (ChAT) were counted, and the density of glial subpopulations was determined by using antibodies specific for glial fibrillary acidic protein (GFAP) and s100β protein. Oxaliplatin treatment induced significant reduction of sensory and adrenergic innervations, as well as the total number and proportion of ChAT-IR neurons, and GFAP-IR glia, but increased s100β expression within the myenteric plexus of the distal colon. Treatment with oxaliplatin significantly alters nerve fibers and glial cells in the colonic myenteric plexus, which could contribute to long-term gastrointestinal side effects following chemotherapeutic treatment.

Lymphatics and colorectal liver metastases: the case for sentinel node mapping

BACKGROUND

Hepatic resection remains the treatment of choice for patients with colorectal liver metastases (CLM). Indications for hepatic resection have been extended to include extrahepatic lymph node groups, resulting in increased survival benefits. The identification of specific lymph pathways and involved nodes is necessary to support the development of guidelines for a more focused approach to the management of this disease. The feasibility of sentinel node mapping should be investigated to define specific lymphatic groups involved in CLM.

METHODS

Scientific papers published from 1950 to 2012 were sought and extracted from the MEDLINE, PubMed and University of Melbourne databases.

RESULTS

Several studies have reported microscopic lymph node involvement in 10-15% of patients undergoing hepatic resection for CLM in which no macroscopic involvement was evident. In retrospect, over 80% of lymphadenectomies are proven unnecessary. Traditional imaging modalities have limited predictive value in detecting lymph node involvement. Sentinel node mapping has proved an extremely accurate tool in detecting lymph node involvement and can identify patients in whom lymphadenectomy may be beneficial.

CONCLUSIONS

Current imaging techniques are inadequate to detect microscopic lymph node involvement in patients with resectable CLM. The use of sentinel node mapping is proposed to identify nodal groups involved and provide management strategies.