Reliable prognostic markers based on biopsy specimens of colorectal cancer (CRC) are currently missing. We hypothesize that assessment of T-cell infiltration in biopsies of CRC may predict patient survival and TNM-stage before surgery. Pre-operative biopsies and matched resection specimens from 130 CRC patients treated from 2002-2011 were included in this study. Whole tissue sections of biopsy material and primary tumors were immunostained for pancytokeratin and CD8 or CD45RO. Stromal (s) and intraepithelial (i) T-cell infiltrates were analyzed for prediction of patient survival as well as clinical and pathological TNM-stage of the primary tumor. CD8 T-cell infiltration in the preoperative biopsy was significantly associated with favorable overall survival (CD8i p = 0.0026; CD8s p = 0.0053) in patients with primary CRC independently of TNM-stage and postoperative therapy (HR [CD8i] = 0.55 (95% CI: 0.36-0.82), p = 0.0038; HR [CD8s] = 0.72 (95% CI: 0.57-0.9), p = 0.0049). High numbers of CD8i in the biopsy predicted earlier pT-stage (p < 0.0001) as well as absence of nodal metastasis (p = 0.0015), tumor deposits (p = 0.0117), lymphatic (p = 0.008) and venous invasion (p = 0.0433) in the primary tumor. Infiltration by CD45ROs cells was independently associated with longer survival (HR = 0.76 (95% CI: 0.61-0.96), p = 0.0231) and predicted absence of venous invasion (p = 0.0025). CD8 counts were positively correlated between biopsies and the primary tumor (r = 0.42; p < 0.0001) and were reproducible between observers (ICC [CD8i] = 0.95, ICC [CD8s] = 0.75). For CD45RO, reproducibility was poor to moderate (ICC [CD45i] = 0.16, ICC [CD45s] = 0.49) and correlation with immune infiltration in the primary tumor was fair and non-significant (r[CD45s] = 0.16; p = 0.2864). For both markers, no significant relationship was observed with radiographic T-stage, N-stage or M-stage, indicating that assessment of T-cells in biopsy material can add additional information to clinical staging in the pre-operative setting. T-cell infiltration in pre-operative biopsy specimens of CRC is an independent favorable prognostic factor and strongly correlates with absence of nodal metastasis in the resection specimen. Quantification of CD8i is highly reproducible and allows superior prediction of clinicopathological features as compared to CD45RO. The assessment of CD8i infiltration in biopsies is recommended for prospective investigation.

Chemokines and their cognate receptors play a major role in modulating inflammatory responses. Depending on their ligand binding, chemokine receptors can stimulate both immune activating and inhibi...

Talimogene laherparepvec (T-VEC), a first-in-class oncolytic viral immunotherapy, enhances tumor-specific immune activation. T-VEC combined with atezolizumab, which blocks inhibitor T-cell checkpoints, could provide greater benefit than either agent alone. Safety/efficacy of the combination was explored in patients with triple negative breast cancer (TNBC) or colorectal cancer (CRC) with liver metastases. In this phase Ib, multicenter, open-label, parallel cohort study of adults with TNBC or CRC with liver metastases, T-VEC (10⁶ then 10⁸ PFU/ml; ≤4 ml) was administered into hepatic lesions via image-guided injection every 21 (±3) days. Atezolizumab 1200 mg was given on day 1 and every 21 (±3) days thereafter. Treatment continued until patients experienced dose-limiting toxicity (DLT), had complete response, progressive disease, needed alternative anticancer treatment, or withdrew due to an adverse event (AE). The primary endpoint was DLT incidence, and secondary endpoints included efficacy and AEs. Between 19 March 2018 and 6 November 2020, 11 patients with TNBC were enrolled (safety analysis set: n = 10); between 19 March 2018 and 16 October 2019, 25 patients with CRC were enrolled (safety analysis set: n = 24). For the 5 patients in the TNBC DLT analysis set, no patient had DLT; for the 18 patients in the CRC DLT analysis set, 3 (17%) had DLT, all serious AEs. AEs were reported by 9 (90%) TNBC and 23 (96%) CRC patients, the majority with grade ≥3 [TNBC, 7 (70%); CRC, 13 (54%)], and 1 was fatal [CRC, 1 (4%)]. Evidence of efficacy was limited. Overall response rate was 10% (95% confidence interval 0.3-44.5) for TNBC; one (10%) patient had a partial response. For CRC, no patients had a response; 14 (58%) were unassessable. The safety profile reflected known risks with T-VEC including risks of intrahepatic injection; no unexpected safety findings from addition of atezolizumab to T-VEC were observed. Limited evidence of antitumor activity was observed.

Purpose: Gene fusions involving R-spondin (RSPOfp) and RNF43 mutations have been shown to drive Wnt-dependent tumor initiation in colorectal cancer. Herein, we aimed to characterize the molecular features of RSPOfp/RNF43 mutated (mut) compared with wild-type (WT) colorectal cancers to gain insights into potential rationales for therapeutic strategies. Experimental Design: A discovery cohort was classified for RSPOfp/RNF43 status using DNA/RNA sequencing and IHC. An independent cohort was used to validate our findings. Results: The discovery cohort consisted of 7,245 colorectal cancer samples. RSPOfp and RNF43 mutations were detected in 1.3% (n = 94) and 6.1% (n = 443) of cases. We found 5 RSPO fusion events that had not previously been reported (e.g., IFNGR1–RSPO3). RNF43-mut tumors were associated with right-sided primary tumors. No RSPOfp tumors had RNF43 mutations. In comparison with WT colorectal cancers, RSPOfp tumors were characterized by a higher frequency of BRAF, BMPR1A, and SMAD4 mutations. APC mutations were observed in only a minority of RSPOfp-positive compared with WT cases (4.4% vs. 81.4%). Regarding RNF43 mutations, a higher rate of KMT2D and BRAF mutations were detectable compared with WT samples. Although RNF43 mutations were associated with a microsatellite instability (MSI-H)/mismatch repair deficiency (dMMR) phenotype (64.3%), and a tumor mutation burden ≥10 mt/Mb (65.8%), RSPOfp was not associated with MSI-H/dMMR. The validation cohort replicated our genetic findings. Conclusions: This is the largest series of RSPOfp/RNF43-mut colorectal cancers reported to date. Comprehensive molecular analyses asserted the unique molecular landscape associated with RSPO/RNF43 and suggested potential alternative strategies to overcome the low clinical impact of Wnt-targeted agents and immunotherapy.

Introduction: LAG-3 is an inhibitory immune checkpoint molecule that suppresses T cell activation and inflammatory cytokine secretion. T cell density in the tumor microenvironment of colon cancer plays an important role in the host’s immunosurveillance. We therefore hypothesized that LAG-3 expression on tumor-infiltrating lymphocytes (TILs) predicts outcome in patients with stage II colon cancer. Patients and Methods: Immunohistochemical staining for LAG-3 was performed on tissue microarrays (TMAs) of formalin-fixed paraffin-embedded tissue from 142 stage II colon cancer patients. LAG-3 expression was assessed in TILs within both the tumor front and tumor center and scored as either positive or negative. The primary endpoint was disease-free survival (DFS). Results: In patients diagnosed with stage II colon cancer, the presence of LAG-3 expression on TILs was significantly associated with better 5-year DFS (HR 0.34, 95% CI 0.14–0.80, p = 0.009). The effect on DFS was mainly due to LAG-3-positive TILs in the tumor front (HR 0.33, 95% CI 0.13–0.82, p = 0.012). Conclusion: Assessment of LAG-3 might help to predict outcomes in patients with stage II colon cancer and potentially identify those patients who might benefit from adjuvant chemotherapy. Therefore, LAG-3 may serve as a prognostic biomarker in stage II colon cancer.