Comprehensive data of 3525 patients newly diagnosed with colorectal liver metastasis between 2013 and 2014: 2nd report of a nationwide survey in Japan

Prognostic Role of the Intrahepatic Lymphatic System in Liver Cancer

Although several prognosticators, such as lymph node metastasis (LNM), were reported for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC), the prognostic impact of intrahepatic lymphatic vessel invasion (LVI) in liver cancer has rarely been reported. We sought to clarify the prognostic impact of intrahepatic lymphatic system involvement in liver cancer. We systematically reviewed retrospective studies that described LVI and clinical outcomes of liver cancer and also included studies that investigated tumor-associated lymphangiogenesis. We conducted a meta-analysis using RevMan software (version 5.4.1; Cochrane Collaboration, Oxford, UK). The prognostic impact of intrahepatic LVI in HCC was not reported previously. However, tumor-associated lymphangiogenesis reportedly correlates with prognosis after HCC resection. The prognostic impact of intrahepatic LVI was reported severally for ICC and a meta-analysis showed that overall survival was poorer in patients with positive LVI than with negative LVI after resection of ICC. Lymphangiogenesis was also reported to predict unfavorable prognosis in ICC. Regarding colorectal liver metastases, LVI was identified as a poor prognosticator in a meta-analysis. A few reports showed correlations between LVI/lymphangiogenesis and LNM in liver cancer. LVI and lymphangiogenesis showed worse prognostic impacts for liver cancer than their absence, but further study is needed.

Precision Surgery of Colorectal Liver Metastases in the Current Era: A Systematic Review

Liver resection for colorectal liver metastases (CRLM) is widely considered the treatment with the highest curative potential. However, not all patients derive the same oncological benefit, underlining the need for better patient stratification and treatment allocation. In this context, we performed a systematic review of the literature to determine the role of RAS status in selecting the optimal surgical strategy. Evidence comparing anatomical with non-anatomical resections depending on RAS mutational status was scarce and conflicting, with two studies reporting superiority in mutated RAS (mutRAS) patients and two studies reporting equivalent outcomes. The rate of incomplete microscopic resection (R1) was found to be increased among mutRAS patients, possibly due to higher micrometastatic spread lateral to the primary lesion. The impact of R1 resection margins was evaluated separately for mutRAS and wild-type patients in three studies, of which, two indicated an additive detriment to long-term survival in the former group. In the current era of precision surgery, RAS status can be utilized to predict the efficacy of liver resection in the treatment of CRLM, avoiding a potentially morbid operation in patients with adverse tumor profiles.

Impact of anatomical liver resection on patient survival in KRAS-wild-type colorectal liver metastasis: A multicenter retrospective study

BACKGROUND

Liver resection is a standard therapy for colorectal liver metastasis. However, the impact of anatomical resection and nonanatomical resection on the survival in patients with Kirsten rat sarcoma-wild-type and Kirsten rat sarcoma-mutated colorectal liver metastasis remain unclear. We investigated whether anatomical resection versus nonanatomical resection improves survival in colorectal liver metastasis stratified by Kirsten rat sarcoma mutational status.

METHODS

Among 639 consecutive patients with colorectal liver metastasis who underwent primary liver resection between January 2008 and December 2017, 349 patients were excluded due to their unknown Kirsten rat sarcoma mutational status, or due to receiving anatomical resection with concomitant non-anatomical resection, radiofrequency, or R2 resection. Accordingly, 290 patients with colorectal liver metastasis were retrospectively assessed. The relationships between resection types and survival were investigated in Kirsten rat sarcoma-wild-type and -mutated groups.

RESULTS

Anatomical resection was performed in 77/186 (41%) and 44/104 (42%) patients with Kirsten rat sarcoma-wild-type and Kirsten rat sarcoma-mutated genetic statuses, respectively. For both, the clinical-pathologic factors were comparable, except a larger maximum tumor size and surgical margin were observed in anatomical resection cases. Anatomical resection patients had significantly longer recurrence-free survival and overall survival than nonanatomical resection cases in the Kirsten rat sarcoma-wild-type group (recurrence-free survival, P < .001; overall survival, P = .005). No significant recurrence-free survival or overall survival differences were observed between Kirsten rat sarcoma-mutated anatomical resection and non-anatomical resection (recurrence-free survival, P = .132; overall survival, P = .563). Although, intrahepatic recurrence in Kirsten rat sarcoma-wild-type and -mutated colorectal liver metastasis was comparable (P = .973), extrahepatic recurrence was increased in Kirsten rat sarcoma-mutated versus -wild-type colorectal liver metastasis (P < .001).

CONCLUSION

In contrast to Kirsten rat sarcoma-mutated colorectal liver metastasis with higher extrahepatic recurrence after liver resection, local liver control via anatomical resection improved the postoperative survival in patients with Kirsten rat sarcoma-wild-type colorectal liver metastasis.

A randomized controlled trial of surgery and postoperative modified FOLFOX6 versus surgery and perioperative modified FOLFOX6 plus cetuximab in patients with KRAS wild-type resectable colorectal liver metastases: EXPERT study

PURPOSE

To clarify the efficacy of perioperative chemotherapy for the patients with resectable colorectal liver metastases (CLM), we conducted a multicenter randomized phase III trial to compare surgery followed by postoperative FOLFOX regimen with perioperative FOLFOX regimen plus cetuximab in patients with KRAS wild-type resectable CLM.

METHODS

Patients who had KRAS wild-type resectable CLM having one to eight liver nodules without extrahepatic disease were randomly assigned to the postoperative chemotherapy group, wherein up-front hepatectomy was performed followed by 12 cycles of postoperative modified FOLFOX6, and the perioperative chemotherapy group (experimental), wherein six cycles of preoperative modified FOLFOX6 plus cetuximab were performed followed by hepatectomy and six cycles of postoperative modified FOLFOX6 plus cetuximab. The primary endpoint was progression-free survival (PFS).

RESULTS

There were 37 patients in postoperative chemotherapy group and 40 patients in the perioperative chemotherapy group who were analyzed. Baseline characteristics were well-balanced between groups. The PFS and overall survival (OS) showed no significant difference (PFS, hazard ratio 1.18 [95% confidence interval 0.69-2.01], P = 0.539: OS, 1.03 [0.46-2.29], P = 0.950). In the postoperative chemotherapy group, 35.1% had a 3-year PFS, and 86.5% had a 3-year OS. Meanwhile, in the perioperative chemotherapy group, 30.0% had a 3-year PFS, and 74.4% had a 3-year OS.

CONCLUSION

There was no difference in survival found between the group of the perioperative chemotherapy plus cetuximab and that of the postoperative chemotherapy in the cohort of our study. The study was registered in the University Hospital Medical Information Network (UMIN000007787).

Relationship between hepatic venous anatomy and hepatic venous blood loss during hepatectomy

PURPOSE

Predicting increased blood loss based on anatomical intervascular relationships is essential in major hepatectomy.

METHODS

We assessed 63 consecutive patients undergoing anatomical hepatectomy exposing the hepatic vein (HV) trunk at two institutes. Correlations between anatomical alterations of the hepatic inferior vena cava (IVC), HV, hepatic IVC, or right atrium (RA) and the blood loss per standard weight (BLSW) or blood transfusion (n = 18) were analyzed. The results of IVC partial clamping (PC) were additionally examined.

RESULTS

The BLSW in type V-up anatomical morphology was significantly higher than that in straight type (p < 0.05). The parameters associated with an increased BLSW (> 13.5 mL/kg) were tumor size (> 4 cm), prothrombin activity (< 87%), CVP (> 7 mmHg), area of suprahepatic IVC (< 360 mm²), IVC-RA gap (> 28 mm), longitudinal angle of IVC (< 160°), and axial angle of the MHV (< 55°). A multivariate analysis revealed that a high IVC-RA gap was a significant independent risk factor (odds ratio; 4.32, p < 0.05). Among 25 patients undergoing IVC-PC, only three showed a remarkable decrease in hepatic venous bleeding. No other statistically significant differences in the surgical records were observed in most cases.

CONCLUSION

The IVC-RA gap might be a promising novel predictive parameter reflecting increased blood loss leading to blood transfusion in anatomical hepatectomy.