Integrating systemic and surgical approaches to treating metastatic colorectal cancer

Melatonin in Cancer Treatment: Current Knowledge and Future Opportunities

Melatonin is a pleotropic molecule with numerous biological activities. Epidemiological and experimental studies have documented that melatonin could inhibit different types of cancer in vitro and in vivo. Results showed the involvement of melatonin in different anticancer mechanisms including apoptosis induction, cell proliferation inhibition, reduction in tumor growth and metastases, reduction in the side effects associated with chemotherapy and radiotherapy, decreasing drug resistance in cancer therapy, and augmentation of the therapeutic effects of conventional anticancer therapies. Clinical trials revealed that melatonin is an effective adjuvant drug to all conventional therapies. This review summarized melatonin biosynthesis, availability from natural sources, metabolism, bioavailability, anticancer mechanisms of melatonin, its use in clinical trials, and pharmaceutical formulation. Studies discussed in this review will provide a solid foundation for researchers and physicians to design and develop new therapies to treat and prevent cancer using melatonin.

The role of melatonin in colorectal cancer treatment: a comprehensive review

Colorectal cancer (CRC) is one of the most common types of cancer worldwide, known as the second leading cause of cancer-related deaths annually. Currently, multimodal treatment strategies, including surgical resection, combined with chemotherapy and radiotherapy, have been used as conventional treatments in patients with CRC. However, clinical outcome of advanced stage disease remains relatively discouraging, due mainly to appearance of CRC chemoresistance, toxicity, and other detrimental side effects. New strategies to overcome these limitations are essential. During the last decades, melatonin (MLT) has been shown to be a potent antiproliferative, anti-metastatic agent with cytotoxic effects on different types of human malignancies, including CRC. Hence, this comprehensive review compiles the available experimental and clinical data analyzing the effects of MLT treatment in CRC patients and its underlying molecular mechanisms.

The adaptation of colorectal cancer cells when forming metastases in the liver: expression of associated genes and pathways in a mouse model

Background

Colorectal cancer (CRC) is the second leading cause of cancer-related death in men and women. Systemic disease with metastatic spread to distant sites such as the liver reduces the survival rate considerably. The aim of this study was to investigate the changes in gene expression that occur on invasion and expansion of CRC cells when forming metastases in the liver.

Methods

The livers of syngeneic C57BL/6NCrl mice were inoculated with 1 million CRC cells (CMT-93) via the portal vein, leading to the stable formation of metastases within 4 weeks. RNA sequencing performed on the Illumina platform was employed to evaluate the expression profiles of more than 14,000 genes, utilizing the RNA of the cell line cells and liver metastases as well as from corresponding tumour-free liver.

Results

A total of 3329 differentially expressed genes (DEGs) were identified when cultured CMT-93 cells propagated as metastases in the liver. Hierarchical clustering on heat maps demonstrated the clear changes in gene expression of CMT-93 cells on propagation in the liver. Gene ontology analysis determined inflammation, angiogenesis, and signal transduction as the top three relevant biological processes involved. Using a selection list, matrix metallopeptidases 2, 7, and 9, wnt inhibitory factor, and chemokine receptor 4 were the top five significantly dysregulated genes.

Conclusion

Bioinformatics assists in elucidating the factors and processes involved in CRC liver metastasis. Our results support the notion of an invasion-metastasis cascade involving CRC cells forming metastases on successful invasion and expansion within the liver. Furthermore, we identified a gene expression signature correlating strongly with invasiveness and migration. Our findings may guide future research on novel therapeutic targets in the treatment of CRC liver metastasis.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-017-3342-1) contains supplementary material, which is available to authorized users.

Robust evidence for long-term survival with 90Y radioembolization in chemorefractory liver-predominant metastatic colorectal cancer

OBJECTIVES

Our aim was to provide further evidence for the efficacy/safety of radioembolization using yttrium-90-resin microspheres for unresectable chemorefractory liver metastases from colorectal cancer (mCRC).

METHODS

We followed 104 consecutively treated patients until death. Overall survival (OS) was calculated from the day of the first radioembolization procedure. Response was defined by changes in tumour volume as defined by Response Evaluation Criteria in Solid Tumours (RECIST) v1.0 and/or a ≥30 % reduction in serum carcinoembryonic antigen (CEA) at 3 months.

RESULTS

Survival varied between 23 months in patients who had a complete response to prior chemotherapy and 13 months in patients with a partial response or stable disease. Median OS also significantly improved (from 5.8 months to 17.1 months) if response durability to radioembolization extended beyond 6 months. Patients with a positive trend in CEA serum levels (≥30 % reduction) at 3 months post-radioembolization also had a survival advantage compared with those who did not: 15.0 vs 6.7 months. Radioembolization was well tolerated. Grade 3 increases in bilirubin were reported in 5.0 % of patients at 3 months postprocedure.

CONCLUSIONS

After multiple chemotherapies, many patients still have a good performance status and are eligible for radioembolization. This single procedure can achieve meaningful survivals and is generally well tolerated.

KEY POINTS

• After multiple chemotherapies, many patients are still eligible for radioembolization (RE). • RE can achieve meaningful survival in patients with chemorefractory liver-predominant metastatic colorectal cancer (mCRC). • Tumour responsiveness to prior systemic treatments is a significant determinant of overall survival (OS) after RE. • Radioembolization in patients with a good performance status is generally well tolerated.

Outcomes of Simultaneous Major Liver Resection and Colorectal Surgery for Colorectal Liver Metastases

BACKGROUND

The optimal surgical strategy for treating colorectal cancer liver metastases (CRLM) in patients requiring major liver resection (MLR) is controversial, especially in rectal cancer patients.

METHOD

Between March 2004 and January 2015, 103 patients underwent MLR for CRLM and underwent MLR simultaneously with colorectal surgery (simultaneous group; n = 55) or MLR after colorectal surgery (liver-only group; n = 48).

RESULTS

There were no significant differences in sex, age, ASA score, BMI, size and number of liver metastases, liver resection margin, surgical outcomes, and estimated blood loss. The rates of postoperative complications (simultaneous group vs. liver-only group; 76.4 % vs. 62.5 %; P = 0.126) and major complications (29.0 % vs. 25.0 %; P = 0.513) were also similar in both groups. The time to starting a soft diet was longer in the simultaneous group (6.0 days vs. 3.4 days; P < 0.001), but the length of hospital stay was similar (14.9 days vs. 13.3 days; P = 0.345). There were no perioperative deaths, anastomotic leakage, or septic complications. Among patients who underwent rectal surgery, the frequency of complications was greater in the simultaneous group (87.0 % vs. 56.2 %; P = 0.031), but there was no difference in major complications (34.7 % vs. 25.0 %; P = 0.822). The postoperative morbidity index was 0.204 and 0.180 in the simultaneous and liver-only groups, respectively, in all patients, and was 0.227 and 0.136, respectively, in the rectal surgery subgroup.

CONCLUSION

Simultaneous MLR is feasible and safe in synchronous CRLM patients, including rectal cancer patients.

Surgical Management of Liver Metastases From Colorectal Cancer

Surgical resection remains one of the major curative treatment options available to patients with colorectal liver metastases. Surgery and chemotherapy form the backbone of the treatment in patients with colorectal liver metastases. With more effective chemotherapy regimens being available, the optimal timing and sequencing of treatments are important. A multidisciplinary approach with the involvement of medical oncologists and surgical oncologists from the beginning is crucial. Identification of the clinical and molecular prognostic factors may help personalize the treatment approaches for these patients. This article provides an overview of the surgical management of colorectal liver metastases.