The Effect of Histopathological Growth Patterns of Colorectal Liver Metastases on the Survival Benefit of Adjuvant Hepatic Arterial Infusion Pump Chemotherapy.

BACKGROUND: Histopathological growth patterns (HGPs) are a prognostic biomarker in colorectal liver metastases (CRLM). Desmoplastic HGP (dHGP) is associated with liver-only recurrence and superior overall survival (OS), while non-dHGP is associated with multi-organ recurrence and inferior OS. This study investigated the predictive value of HGPs for adjuvant hepatic arterial infusion pump (HAIP) chemotherapy in CRLM. METHODS: Patients undergoing resection of CRLM and perioperative systemic chemotherapy in two centers were included. Survival outcomes and the predictive value of HAIP versus no HAIP per HGP group were evaluated through Kaplan-Meier and Cox regression methods, respectively. RESULTS: We included 1233 patients. In the dHGP group (n = 291, 24%), HAIP chemotherapy was administered in 75 patients (26%). In the non-dHGP group (n = 942, 76%), HAIP chemotherapy was administered in 247 patients (26%). dHGP was associated with improved overall survival (OS, HR 0.49, 95% CI 0.32-0.73, p < 0.001). HAIP chemotherapy was associated with improved OS (HR 0.61, 95% CI 0.45-0.82, p < 0.001). No interaction could be demonstrated between HGP and HAIP on OS (HR 1.29, 95% CI 0.72-2.32, p = 0.40). CONCLUSIONS: There is no evidence that HGPs of CRLM modify the survival benefit of adjuvant HAIP chemotherapy in patients with resected CRLM.

Propensity score matching demonstrates similar results for radiofrequency ablation compared to surgical resection in colorectal liver metastases.

PURPOSE: Minimally invasive ablative treatments, such as radiofrequency ablation (RFA), are increasingly used in the curative treatment of patients with colorectal liver metastases (CRLM). Selection bias plays an important role in the evaluation of early and late results between RFA and surgery. The purpose of this study was to evaluate recurrences and oncological survival following these two treatment modalities using single pair propensity score matching. METHODS: Between 2000 and 2018, patients curatively treated for CRLM were included in a multicentre database. Patients were excluded when receiving two-staged treatment, synchronous treatment with primary tumor or combination of modalities. Propensity score matching was used to minimize influence of known covariates, i.e., age, ASA, FONG CRS, location and T-stage of the primary tumor. RESULTS: Before matching, the RFA group contained 39 patients and the surgery group 982 patients, after matching both groups contained 36 patients. After matching, mean age was 69 years (53-86) for RFA and 68 (50-86) for surgery, with a mean tumor size of respectively 2.5 cm (0.8-6.5) and 3.4 cm (1-7.5). Both groups showed similar complication rate according to Clavien-Dindo (17vs.33%; p = 0.18), recurrence rate (58vs.64%; p = 0.09) without significant differences in 5-year DFS and OS (RFA compared to surgery respectively 25vs.37%; p = 0.09 and 42vs.53%; p = 0.09). CONCLUSION: After propensity score matching, RFA showed lower complications and similar oncological survival compared to surgical resection. In patients who are suboptimal candidates for surgery, RFA seems to be a good and safe alternative.

The liver-first approach for locally advanced rectal cancer and synchronous liver metastases.

BACKGROUND: Patients with locally advanced rectal cancer (LARC) and synchronous liver metastases (sRLM) can be treated according to the liver-first approach. This study aimed to evaluate prognostic factors for completing treatment and in how many patients extensive lower pelvic surgery might have been omitted. METHODS: Retrospective analysis of all patients with LARC and sRLM treated at the Erasmus MC Cancer Institute according to the liver-first between 2003 and 2016. RESULTS: In total 129 consecutive patients were included. In 90 patients (70%) the liver-first was completed. Ten patients had a (near) complete response (ypT0-1N0) of their primary tumour. In 36 out of 39 patients not completing the liver-first protocol palliative rectum resection was withheld. Optimal cut-offs for CEA level (53.15 µg/L), size (3.85 cm) and number (4) of RLMs were identified. A preoperative CEA level above 53.15 µg/L was an independent predictor for non-completion of the liver-first protocol (p = 0.005). CONCLUSION: Ten patients had a (near) complete response of their primary tumour and, in retrospect, rectum sparing therapies could have been considered. Together with 36 patient in whom palliative rectum resection was not necessary this entails that nearly 40% patients with LARC and sRLM might be spared major pelvic surgery if the liver-first approach is applied. A predictor (CEA) was found for non-completion of the liver-first protocol. The majority of patients underwent resection of both primary tumour and hepatic metastasis with curative intent. These findings together entail that the liver-first approach may be considered in patients with LARC and sRLM.

Histopathological growth patterns of colorectal liver metastasis exhibit little heterogeneity and can be determined with a high diagnostic accuracy.

Colorectal liver metastases (CRLM) exhibit distinct histopathological growth patterns (HGPs) that are indicative of prognosis following surgical treatment. This study aims to assess the reliability and replicability of this histological biomarker. Within and between metastasis HGP concordance was analysed in patients who underwent surgery for CRLM. An independent cohort was used for external validation. Within metastasis concordance was assessed in CRLM with ≥ 2 tissue blocks. Similarly, concordance amongst multiple metastases was determined in patients with ≥ 2 resected CRLM. Diagnostic accuracy [expressed in area under the curve (AUC)] was compared by number of blocks and number of metastases scored. Interobserver agreement (Cohen's k) compared to the gold standard was determined for a pathologist and a PhD candidate without experience in HGP assessment after one and two training sessions. Both the within (95%, n = 825) and the between metastasis (90%, n = 363) HGP concordance was high. These results could be replicated in the external validation cohort with a within and between metastasis concordance of 97% and 94%, respectively. Diagnostic accuracy improved when scoring 2 versus 1 blocks(s) or CRLM (AUC = 95.9 vs. 97.7 [p = 0.039] and AUC = 96.5 vs. 93.3 [p = 0.026], respectively), but not when scoring 3 versus 2 blocks or CRLM (both p > 0.2). After two training sessions the interobserver agreement for both the pathologist and the PhD candidate were excellent (k = 0.953 and k = 0.951, respectively). The histopathological growth patterns of colorectal liver metastasis exhibit little heterogeneity and can be determined with a high diagnostic accuracy, making them a reliable and replicable histological biomarker.