Does the site of primary colorectal cancer influence the outcome after resection of isolated liver metastases?

Prognostic value of the combination of primary tumor location and RAS mutational status on patients with colorectal liver metastasis undergoing hepatectomy

OBJECTIVE

To assess prognostic influences of RAS mutational status and primary tumor site on cases with colorectal liver metastasis (CRLM) who underwent hepatectomy.

METHODS

Clinicopathological data of 762 patients with CRLM who underwent hepatectomy between January 2000 and November 2018 were retrospectively analyzed. The left-sided tumors (LST) included tumors located in the splenic flexure, descending colon, sigmoid colon, and rectum; while right-sided tumors (RST) included those located in the cecum, ascending colon, and transverse colon. RAS mutational status was determined using Sanger sequencing or next-generation sequencing, including KRAS (Codons 12, 13, and 61) and NRAS (Codons 12, 13, and 61), which were defined as wild-type (RASwt) and mutant-type (RASmut), respectively. Survival curves were plotted using the Kaplan-Meier plotter and compared by the log rank test. The clinicopathological data were analyzed using univariate and multivariate analyses.

RESULTS

The 5-year overall survival (OS) in the LST group was longer than that in the RST group (OS: 47.1% vs. 31.0%, p = 0.000, respectively), and the OS in the RASwt group was longer compared with that in the RASmut group (OS: 53.6% vs. 24.0%, p = 0.000). Besides, overall survival of the patients after hepatectomy was alternative, which was stratified by primary tumor site, with the 1-, 3-, and 5-year survival rates of 93.1%, 62.1%, and 47.1% for patients with LST, and 91.1%, 42.8%, and 31.0% for patients with RST, respectively. OS and disease-free survival (DFS) were significantly different stratified by RAS mutational status, with the 1-, 3-, and 5-year rates of 96.9%, 67.9%, and 53.6% for patients with RASwt tumors, and 85.7%, 41.5%, and 24.0% for patients with RASmut tumors, respectively. The 1-, 3-, and 5-year DFS rates were 51.9%, 30.0%, and 26.7% for patients with RASwt tumors, and 35.8%, 18.2%, and 14.9% for patients with RASmut tumors, respectively. The results of multivariate analysis showed that RAS mutational status and primary tumor site were both independent influencing factors of OS.

CONCLUSION

RAS mutational status and primary tumor site affect OS independently in CRLM patients undergoing hepatectomy. The worse prognosis of RST cannot be simply attributed to the imbalance of RAS mutational status in different primary tumor sites.

The Prognostic Impact of Primary Tumor Site Differs According to the KRAS Mutational Status: A Study By the International Genetic Consortium for Colorectal Liver Metastasis

OBJECTIVE

To examine the prognostic impact of tumor laterality in colon cancer liver metastases (CLM) after stratifying by Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) mutational status.

BACKGROUND

Although some studies have demonstrated that patients with CLM from a right sided (RS) primary cancer fare worse, others have found equivocal outcomes of patients with CLM with RS versus left-sided (LS) primary tumors. Importantly, recent evidence from unresectable metastatic CRC suggests that tumor laterality impacts prognosis only in those with wild-type tumors.

METHODS

Patients with rectal or transverse colon tumors and those with unknown KRAS mutational status were excluded from analysis. The prognostic impact of RS versus LS primary CRC was determined after stratifying by KRAS mutational status.

RESULTS

277 patients had a RS (38.6%) and 441 (61.4%) had a LS tumor. Approximately one-third of tumors (28.1%) harbored KRAS mutations. In the entire cohort, RS was associated with worse 5-year overall survival (OS) compared with LS (39.4% vs 50.8%, P = 0.03) and remained significantly associated with worse OS in the multivariable analysis (hazard ratio 1.45, P = 0.04). In wild-type patients, a worse 5-year OS associated with a RS tumor was evident in univariable analysis (43.7% vs 55.5%, P = 0.02) and persisted in multivariable analysis (hazard ratio 1.49, P = 0.01). In contrast, among patients with KRAS mutated tumors, tumor laterality had no impact on 5-year OS, even in the univariable analysis (32.8% vs 34.0%, P = 0.38).

CONCLUSIONS

This study demonstrated, for the first time, that the prognostic impact of primary tumor side differs according to KRAS mutational status. RS tumors were associated with worse survival only in patients with wild-type tumors.

Primary Tumor Sidedness, RAS and BRAF Mutations and MSI Status as Prognostic Factors in Patients with Colorectal Liver Metastases Treated with Surgery and Thermal Ablation: Results from the Amsterdam Colorectal Liver Met Registry (AmCORE)

The aim of this study was to assess primary tumor sidedness of colorectal cancer (CRC), rat sarcoma viral oncogene homolog (RAS) and v-raf murine sarcoma viral oncogene homolog B (BRAF) mutations and microsatellite instability (MSI) status as prognostic factors predicting complications, survival outcomes, and local tumor progression (LTP) following surgery and thermal ablation in patients with colorectal liver metastases (CRLM). This Amsterdam Colorectal Liver Met Registry (AmCORE) based study included 520 patients, 774 procedures, and 2101 tumors undergoing local treatment (resection and/or thermal ablation) from 2000 to 2021. Outcomes following local treatment were analyzed for primary tumor sidedness of CRC, RAS, and BRAF mutations and MSI status. The Kaplan–Meier method was used to estimate local tumor progression-free survival (LTPFS), local control (LC), distant progression-free survival (DPFS), and overall survival (OS). Uni- and multivariable analyses were performed based on Cox proportional hazards model. The chi-square test was used to analyze complications. Complications (p = 0.485), OS (p = 0.252), LTPFS (p = 0.939), and LC (p = 0.423) was not associated with tumor-sidedness. Compared to right-sided colon cancer (CC) (reference HR 1.000), DPFS was superior for left-sided CC and rectal cancer (p = 0.018) with an HR for left-sided CC of 0.742 (95% CI, 0.596–0.923) and for RC of 0.760 (95% CI, 0.597–0.966). Regarding RAS mutations, no significant difference was found in OS (p = 0.116). DPFS (p = 0.001), LTPFS (p = 0.039), and LC (p = 0.025) were significantly lower in the RAS mutation group. Though no difference in LTPFS was found between RAS wildtype and RAS mutated CRLM following resection (p = 0.532), LTPFS was worse for RAS mutated tumors compared to RAS wildtype following thermal ablation (p = 0.037). OS was significantly lower in the BRAF mutation group (p < 0.001) and in the MSI group (p < 0.001) following local treatment, while both did not affect DPFS, LTPFS, and LC. This AmCORE based study suggests the necessity of wider margins to reduce LTP rates in patients with RAS mutated CRLM, especially for thermal ablation. Upfront knowledge regarding molecular biomarkers may contribute to improved oncological outcomes.

PRIMARY TUMOR LYMPHOVASCULAR INVASION NEGATIVELY AFFECTS SURVIVAL AFTER COLORECTAL LIVER METASTASIS RESECTION?

BACKGROUND

About 50% of the patients with colorectal adenocarcinoma will present with liver metastasis and 20% are synchronic. Liver resection is associated with improvement in survival in comparison to chemotherapy alone.

AIM

To analyze the overall survival in patients submitted to liver resection of colorectal cancer metastasis and prognostic factors related to the primary and secondary tumors.

METHODS

A retrospective analysis of a prospectively maintained database regarding demographic, primary tumor and liver metastasis characteristics.

RESULTS

There were 84 liver resections due to colorectal cancer metastasis in the period. The 5-year disease-free and overall survivals were 27.5% and 48.8% respectively. The statistically significant factors for survival were tumor grade (p=0.050), lymphovascular invasion (p=0.021), synchronous metastasis (p=0.020), as well as number (p=0.004), bilobar distribution (p=0.019) and diameter of the liver metastasis over 50 mm (p=0.027). Remained as independent negative predictive factors: lymphovascular invasion (HR=2.7; CI 95% 1.106-6.768; p=0.029), synchronous metastasis (HR=2.8; CI 95% 1.069-7.365; p=0.036) and four or more liver metastasis (HR=1.7; CI 95% 1.046-2.967; p=0.033).

CONCLUSION

The resection of liver metastasis of colorectal adenocarcinoma leads to good survival rates. Lymphovascular invasion was the single prognostic factor related to the primary tumor. Synchronous disease and four or more metastasis were the most significant factors related to the secondary tumor.

Effect of Primary Tumor Location on Postmetastasectomy Survival in Patients with Colorectal Cancer Liver Metastasis

BACKGROUND

The effects of primary tumor location on colorectal liver metastasis (CRLM) and post-hepatic-metastasectomy overall survival (OS) are controversial. This study evaluated the difference in post-hepatic-metastasectomy OS among right-sided colon, left-sided colon, and rectal cancer groups.

METHODS

In total, 381 patients who underwent curative-intent CRLM resection were enrolled. Patients were grouped based on the primary tumor location (right-sided, left-sided, and rectum). The Kaplan-Meier analysis and log-rank test were performed for survival analysis. The univariate and multivariate analyses of clinical and pathological factors were performed using the Cox proportional hazards model.

RESULTS

Significant OS difference was noted among the three groups (log-rank, p = 0.014). The multivariate analysis revealed a 32% lower death risk in left-sided colon cancer compared with right-sided colon cancer (hazard ratio [HR] 0.68, p = 0.042), whereas no OS difference was noted between the rectal cancer and right-sided colon cancer groups. The left- versus right-sided OS advantage was noted only in the KRAS wild-type subgroup (HR 0.46, p = 0.002), and a rectal versus right-sided OS disadvantage was noted in the KRAS mutant subgroup (HR 1.78, p = 0.03).

CONCLUSIONS

The CRLM post-hepatic-metastasectomy OS was superior in left-sided colon cancer than in right-sided colon cancer and was similar in rectal and right-sided colon cancer. The OS difference in different primary tumor locations is dependent on KRAS mutation status, with a decreased left- versus right-sided death risk noted only in KRAS wild-type colon cancer and an increased rectal versus right-sided death risk noted only in KRAS mutant colon cancer.

Impact of primary tumour location on colorectal liver metastases: A systematic review

BACKGROUND

Colorectal cancer (CRC) is the third most common cause of cancer-related death worldwide. Despite significant advances in screening, surgical management and adjuvant therapies, average 5-year survival seldom exceeds 60% in most developed nations. Metastatic disease represents the primary cause of mortality in patients with CRC, and the liver is the most common location for distant tumour spread. Up to 25% of patients are found to have synchronous liver metastases at the time of diagnosis and a further 30%-40% will develop metachronous disease in the course of follow-up. It has been suggested that primary tumour location [right side versus left side, primary tumour location (PTL)] can influence oncological outcomes in this patient group and that this should be considered in prognostic models and therapeutic decision-making algorithms. This suggestion is not universally accepted and there have been conflicting reports in the literature to date.

AIM

To provide a comprehensive summary of the available evidence regarding the impact of PTL on oncological outcomes in patients with colorectal cancer liver metastases (CRCLM).

METHODS

MEDLINE, EMBASE and COCHRANE were searched for relevant publications using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses methodology. Data on oncological outcomes was then extracted from full text articles that met the predefined inclusion criteria.

RESULTS

A total of 41 studies were identified that met predefined inclusion criteria for this review. In 21 out of 38 studies that provided data on overall survival, a statistically significant improvement in overall survival was reported in patients with left sided primary tumours. These studies included a total of 13897 patients compared with 4306 patients in the studies that did not show a significant difference. Eight studies noted a similar trend towards improved disease-free or progression-free survival. Several authors observed distinct patterns of relapse after treatment of hepatic metastases according to PTL; for example hepatic recurrence after treatment of CRCLM appears to occur more aggressively with right-sided CRC.

CONCLUSION

Taken together, the findings of the present review indicate that PTL may have a role as an independent prognostic factor when determining treatment and disease surveillance strategies in CRC. The mechanisms responsible for this variation remain poorly understood, but are likely to relate to molecular, histological and embryological differences, as well as inherent differences in therapeutic sensitivity.

The Association of Tumor Laterality and Survival After Cytoreduction for Colorectal Carcinomatosis

BACKGROUND

Primary tumor location has emerged as an important surrogate for tumor biology in metastatic colorectal cancer treated with systemic chemotherapy. It is unclear if primary tumor location is associated with survival after cytoreductive surgery (CRS) with or without heated intraperitoneal chemotherapy (HIPEC) for colorectal carcinomatosis.

METHODS

Study of a contemporary cohort merged data from the California Cancer Registry, 2004-2012, and the Office of Statewide Health Planning and Development inpatient database. For patients undergoing CRS/HIPEC, clinicopathologic variables, treatment characteristics, and survival were compared by right versus left colon primary site. Survival was analyzed by Cox proportional hazards.

RESULTS

Of 272 patients identified, 128 (47.1%) had right-sided tumors. Left- and right-sided cohorts had similar patient, tumor, and treatment factors. Patients with left-sided primary tumors had significantly prolonged overall survival (mean 34 versus 15.5 mo, P = 0.0010). Factors independently associated with decreased overall survival included age >80 (HR 7.0, P < 0.0001), advanced T4 stage (HR 3.6, P = 0.0031), and positive lymph nodes (HR 2.2, P = 0.0004). Metachronous peritoneal involvement (HR 0.38, P < 0.0001) and left-sided primary tumors (HR 0.72, P = 0.041) were independently associated with improved overall survival.

CONCLUSIONS

This study identifies location of primary tumor as an important determinant of long-term survival after CRS/HIPEC. Patients with left-sided tumors have a more favorable prognosis.

Meta-analysis of the association between primary tumour location and prognosis after surgical resection of colorectal liver metastases

BACKGROUND

Primary tumour location is emerging as an important prognostic factor in localized and metastatic colorectal cancers. However, its prognostic role in colorectal liver metastasis (CRLM) after hepatectomy remains controversial. A systematic review and meta-analysis was undertaken to evaluate its prognostic value.

METHODS

References were identified through searches of PubMed, Embase, Web of Science and the Cochrane Library comparing overall or disease-free survival after hepatic resection between patients with CRLM originating from right- or left-sided colorectal cancers. Data were pooled using hazard ratios (HRs) and 95 per cent confidence intervals according to a random-effects model. Meta-regression and subgroup analyses were conducted to assess the effect of underlying confounding factors on HR estimates and to adjust for this.

RESULTS

The final analysis included 21 953 patients from 45 study cohorts. Compared with left-sided primary tumour location, right-sided location was associated with worse overall survival (HR 1·39, 95 per cent c.i. 1·28 to 1·51; P < 0·001; prediction interval 1·00 to 1·93), and also tended to have a negative impact on disease-free survival (HR 1·18, 1·06 to 1·32; P = 0·004; prediction interval 0·79 to 1·75). Subgroup analysis showed that the negative effect of right-sided primary tumour location on overall survival was more prominent in the non-Asian population (HR 1·47, 1·33 to 1·62) than the Asian population (HR 1·18, 1·05 to 1·32) (P for interaction <0·01).

CONCLUSION

This study demonstrated a prognostic role for primary tumour location in patients with CRLM receiving hepatectomy, especially regarding overall survival. Adding primary tumour location may provide important optimization of prognosis prediction models for CRLM in current use.

The primary tumor location impacts survival outcome of colorectal liver metastases after hepatic resection: A systematic review and meta-analysis

OBJECTIVE

Location of the primary tumor side has become an increasingly prognostic factor for colorectal liver metastasis. The present study was to perform a meta-analysis to investigate if primary right-sided tumor impacted on long-term survival outcome of colorectal liver metastases following local treatment.

METHOD

Eligible trials were identified from the Embase, PubMed, Web of Science and the Cochrane database that were published before October in 2018. English language trials that compared long-term survival outcome of primary left-sided tumor with right-sided tumor colorectal liver metastases following local treatment were included. Hepatic resection for colorectal liver metastases was investigated. The main study outcomes included overall survival and disease free survival of primary right-sided colorectal liver metastases following local treatment. The risk factors of largest tumor size, primary node metastases, multiple tumor and RAS mutation were also analyzed. A systematic review and meta-analysis was done using a fixed-effects model. Hazard ratio with a 95% confidence interval was used to measure the pooled effect.

RESULTS

A total of twelve studies with 6387 patients were included. For primary right-sided colorectal liver metastases patients following hepatic resection, the overall pooled HR for 5-year overall survival rate was 1.354 (95% CI: 1.238-1.482; p = 0.000; I² = 33.7%, p = 0.138). The pooled HR for 5-year disease free survival rate of primary right-sided CRLM in the included studies calculated using the fix-effects model was 1.104 (95% CI: 0.987-1.235; p = 0.084; I² = 0%, p = 0.477).

CONCLUSION

It demonstrated that primary right-sided for colorectal liver metastases location was a significantly worse prognostic factor in terms of overall survival.