Neoadjuvant FOLFOXIRI prior to chemoradiotherapy for high-risk ("ugly") locally advanced rectal cancer: study protocol of a single-arm, multicentre, open-label, phase II trial (MEND-IT).

BACKGROUND: The presence of mesorectal fascia (MRF) invasion, grade 4 extramural venous invasion (EMVI), tumour deposits (TD) or extensive or bilateral extramesorectal (lateral) lymph nodes (LLN) on MRI has been suggested to identify patients with indisputable, extensive locally advanced rectal cancer (LARC), at high risk of treatment failure. The aim of this study is to evaluate whether or not intensified chemotherapy prior to neoadjuvant chemoradiotherapy improves the complete response (CR) rate in these patients. METHODS: This multicentre, single-arm, open-label, phase II trial will include 128 patients with non-metastatic high-risk LARC (hr-LARC), fit for triplet chemotherapy. To ensure a study population with indisputable, unfavourable prognostic characteristics, hr-LARC is defined as LARC with on baseline MRI at least one of the following characteristics; MRF invasion, EMVI grade 4, enlarged bilateral or extensive LLN at high risk of an incomplete resection, or TD. Exclusion criteria are the presence of a homozygous DPD deficiency, distant metastases, any chemotherapy within the past 6 months, previous radiotherapy within the pelvic area precluding standard chemoradiotherapy, and any contraindication for the planned treatment. All patients will be planned for six two-weekly cycles of FOLFOXIRI (5-fluorouracil, leucovorin, oxaliplatin and irinotecan) prior to chemoradiotherapy (25 × 2 Gy or 28 × 1.8 Gy with concomitant capecitabine). A resection will be performed following radiological confirmation of resectable disease after the completion of chemoradiotherapy. A watch and wait strategy is allowed in case of a clinical complete response. The primary endpoint is the CR rate, described as a pathological CR or a sustained clinical CR one year after chemoradiotherapy. The main secondary objectives are long-term oncological outcomes, radiological and pathological response, the number of resections with clear margins, treatment-related toxicity, perioperative complications, health-related costs, and quality of life. DISCUSSION: This trial protocol describes the MEND-IT study. The MEND-IT study aims to evaluate the CR rate after intensified chemotherapy prior to concomitant chemoradiotherapy in a homogeneous group of patients with locally advanced rectal cancer and indisputably unfavourable characteristics, defined as hr-LARC, in order to improve their prognosis. TRIAL REGISTRATION: Clinicaltrials.gov: NCT04838496 , registered on 02-04-2021 Netherlands Trial Register: NL9790. PROTOCOL VERSION: Version 3 dd 11-4-2022.

Diagnostic performance of MRI for staging peritoneal metastases in patients with colorectal cancer after neoadjuvant chemotherapy.

INTRODUCTION: MRI improves the selection of patients with colorectal cancer (CRC) and peritoneal metastases (PM) for cytoreductive surgery by accurately assessing the extent of PM reflected as the peritoneal cancer index (PCI). The performance of MRI after neoadjuvant chemotherapy (NACT) for staging PM, however is unknown. The purpose of this study was to determine whether MRI could also accurately determine the PCI after NACT. MATERIALS AND METHODS: This was a single-centre, retrospective study of patients with PM from CRC or appendiceal origin who received NACT followed by diffusion-weighted (DW)-MRI and surgery from January 2016 to February 2021. Two radiologists assessed the PCI on restaging DW-MRI (mriPCI). The reference standard was the surgical PCI (sPCI). The main outcome was the diagnostic performance of restaging DW-MRI in predicting whether patients were eligible for cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC), defined as a PCI < 21 with metastases on resectable locations. If CRS-HIPEC was performed, the resected peritoneal lesions were assessed and correlated with the final pathological PCI (pPCI). RESULTS: Thirty-three patients were included. Both readers correctly detected all 23 patients with resectable disease. Eight out of ten patients with unresectable disease during staging surgery were detected by both readers with MRI. The intraclass correlation (ICC) between both readers was excellent (0⋅87 (95% CI: 0⋅75 to 0⋅93)). The ICC between pPCI and mriPCI was 0⋅74 (0⋅49-0⋅88) and 0⋅82 (0⋅66-0⋅91) for the 2 readers. Surgical PCI (sPCI) had a similar correlation as mriPCI with pPCI 0⋅82 (0⋅62- 0⋅92)) and 0⋅81 (0⋅57-0⋅92)). CONCLUSION: DW-MRI is a promising tool to reassess the peritoneal cancer index after neoadjuvant chemotherapy.

MiR expression profiles of paired primary colorectal cancer and metastases by next-generation sequencing.

MicroRNAs (miRs) have been recognized as promising biomarkers. It is unknown to what extent tumor-derived miRs are differentially expressed between primary colorectal cancers (pCRCs) and metastatic lesions, and to what extent the expression profiles of tumor tissue differ from the surrounding normal tissue. Next-generation sequencing (NGS) of 220 fresh-frozen samples, including paired primary and metastatic tumor tissue and non-tumorous tissue from 38 patients, revealed expression of 2245 known unique mature miRs and 515 novel candidate miRs. Unsupervised clustering of miR expression profiles of pCRC tissue with paired metastases did not separate the two entities, whereas unsupervised clustering of miR expression profiles of pCRC with normal colorectal mucosa demonstrated complete separation of the tumor samples from their paired normal mucosa. Two hundred and twenty-two miRs differentiated both pCRC and metastases from normal tissue samples (false discovery rate (FDR) <0.05). The highest expressed tumor-specific miRs were miR-21 and miR-92a, both previously described to be involved in CRC with potential as circulating biomarker for early detection. Only eight miRs, 0.5% of the analysed miR transcriptome, were differentially expressed between pCRC and the corresponding metastases (FDR <0.1), consisting of five known miRs (miR-320b, miR-320d, miR-3117, miR-1246 and miR-663b) and three novel candidate miRs (chr 1-2552-5p, chr 8-20656-5p and chr 10-25333-3p). These results indicate that previously unrecognized candidate miRs expressed in advanced CRC were identified using NGS. In addition, miR expression profiles of pCRC and metastatic lesions are highly comparable and may be of similar predictive value for prognosis or response to treatment in patients with advanced CRC.

KRAS and BRAF mutations are rare and related to DNA mismatch repair deficiency in gastric cancer from the East and the West: results from a large international multicentre study.

BACKGROUND: Inhibitors of the epidermal growth factor (EGFR) signaling pathway have a major role in the treatment of KRAS wild-type colorectal cancer patients. The EGFR pathway has been shown to be activated in gastric cancer (GC). However, published data on KRAS and BRAF mutation status is limited in GC and has not been compared between GC from different geographic regions. METHODS: The prevalence of KRAS and BRAF mutations was established in 712 GC: 278 GC from the United Kingdom, 230 GC from Japan and 204 GC from Singapore. The relationship between KRAS/BRAF mutation status, DNA mismatch repair (MMR) status, clinicopathological variables and overall survival was analysed. RESULTS: Overall, 30 (4.2%) GC carried a KRAS mutation. In total, 5.8% of the UK GC, 4% of Japan GC and 1.5% of Singapore GC were KRAS mutant. KRAS mutant GC had fewer lymph node metastases in the UK cohort (P=0.005) and were more frequent in elderly patients in the Japan cohort (P=0.034). KRAS mutations were more frequent in MMR-deficient GC in the UK and the Japanese cohort (P<0.05). A BRAF mutation was only detected in a single Japanese GC. CONCLUSIONS: This large multicentre study demonstrated that KRAS mutations and DNA MMR deficiency have a role in a small subgroup of GC irrespective of country of origin, suggesting that this subgroup of GC may have developed along a common pathway. Further studies need to establish whether concomitant mutations or amplifications of other EGFR signalling pathway genes may contribute to the activation of this pathway in GC.

Small bowel adenocarcinoma copy number profiles are more closely related to colorectal than to gastric cancers.

BACKGROUND: Small bowel adenocarcinoma (SBA) is a rare cancer and consequently, the options for clinical trials are limited. As they are treated according to either a colorectal or a gastric cancer regimen and the molecular biology of a tumor is a pivotal determinant for therapy response, chromosomal copy number aberrations were compared with the colorectal and gastric adenocarcinomas. MATERIALS AND METHODS: A total of 85 microsatellite stable (MSS) adenocarcinomas from the stomach, colorectum and small bowel were selected from existing array comparative genomic hybridization (aCGH) datasets. We compared the aCGH profiles of the three tumor sites by supervised analysis and hierarchical clustering. RESULTS: Hierarchical clustering revealed substantial overlap of 27 SBA copy number profiles with matched colorectal adenocarcinomas but less overlap with profiles of gastric adenocarcinomas. DNA copy number aberrations located at chromosomes 1p36.3-p34.3, 4p15.3-q35.2, 9p24.3-p11.1, 13q13.2-q31.3 and 17p13.3-p13.2 were the strongest features discriminating SBAs and colorectal adenocarcinomas from gastric adenocarcinomas. CONCLUSIONS: We show that MSS SBAs are more similar to colorectal than to gastric cancer, based on the 27 genome-wide DNA copy number profiles that are currently available. These molecular similarities provide added support for treatment of MSS small bowel cancers according to colorectal cancer regimens.

Deletion of chromosome 4q predicts outcome in stage II colon cancer patients.

BACKGROUND: Around 30% of all stage II colon cancer patients will relapse and die of their disease. At present no objective parameters to identify high-risk stage II colon cancer patients, who will benefit from adjuvant chemotherapy, have been established. With traditional histopathological features definition of high-risk stage II colon cancer patients is inaccurate. Therefore more objective and robust markers for prediction of relapse are needed. DNA copy number aberrations have proven to be robust prognostic markers, but have not yet been investigated for this specific group of patients. The aim of the present study was to identify chromosomal aberrations that can predict relapse of tumor in patients with stage II colon cancer. MATERIALS AND METHODS: DNA was isolated from 40 formaldehyde fixed paraffin embedded stage II colon cancer samples with extensive clinicopathological data. Samples were hybridized using Comparative Genomic Hybridization (CGH) arrays to determine DNA copy number changes and microsatellite stability was determined by PCR. To analyze differences between stage II colon cancer patients with and without relapse of tumor a Wilcoxon rank-sum test was implemented with multiple testing correction. RESULTS: Stage II colon cancers of patients who had relapse of disease showed significantly more losses on chromosomes 4, 5, 15q, 17q and 18q. In the microsatellite stable (MSS) subgroup (n = 28), only loss of chromosome 4q22.1-4q35.2 was significantly associated with disease relapse (P < 0.05, FDR < 0.15). No differences in clinicopathological characteristics between patients with and without relapse were observed. CONCLUSION: In the present series of MSS stage II colon cancer patients losses on 4q22.1-4q35.2 were associated with worse outcome and these genomic alterations may aid in selecting patients for adjuvant therapy.

Deletion of chromosome 4q predicts outcome in stage II colon cancer patients.

BACKGROUND: Around 30% of all stage II colon cancer patients will relapse and die of their disease. At present no objective parameters to identify high-risk stage II colon cancer patients, who will benefit from adjuvant chemotherapy, have been established. With traditional histopathological features definition of high-risk stage II colon cancer patients is inaccurate. Therefore more objective and robust markers for prediction of relapse are needed. DNA copy number aberrations have proven to be robust prognostic markers, but have not yet been investigated for this specific group of patients. The aim of the present study was to identify chromosomal aberrations that can predict relapse of tumor in patients with stage II colon cancer. MATERIALS AND METHODS: DNA was isolated from 40 formaldehyde fixed paraffin embedded stage II colon cancer samples with extensive clinicopathological data. Samples were hybridized using Comparative Genomic Hybridization (CGH) arrays to determine DNA copy number changes and microsatellite stability was determined by PCR. To analyze differences between stage II colon cancer patients with and without relapse of tumor a Wilcoxon rank-sum test was implemented with multiple testing correction. RESULTS: Stage II colon cancers of patients who had relapse of disease showed significantly more losses on chromosomes 4, 5, 15q, 17q and 18q. In the microsatellite stable (MSS) subgroup (n=28), only loss of chromosome 4q22.1-4q35.2 was significantly associated with disease relapse (p<0.05, FDR<0.15). No differences in clinicopathological characteristics between patients with and without relapse were observed. CONCLUSION: In the present series of MSS stage II colon cancer patients losses on 4q22.1-4q35.2 were associated with worse outcome and these genomic alterations may aid in selecting patients for adjuvant therapy.

Gross genomic damage measured by DNA image cytometry independently predicts gastric cancer patient survival.

BACKGROUND: DNA aneuploidy reflects gross genomic changes. It can be measured by flow cytometry (FCM-DNA) or image cytometry (ICM-DNA). In gastric cancer, the prevalence of DNA aneuploidy has been reported to range from 27 to 100%, with conflicting associations with clinicopathological variables. The aim of our study was to compare the DNA ploidy status measured using FCM-DNA and ICM-DNA in gastric cancer and to evaluate its association with clinicopathological variables. METHODS: Cell nuclei were isolated from 221 formalin-fixed, paraffin-embedded gastric cancer samples. DNA ploidy was assessed using FCM-DNA and ICM-DNA. RESULTS: A total of 178 (80.5%) gastric cancer samples were classified as DNA aneuploid using FCM-DNA, compared with 172 (77.8%) gastric cancer samples when using ICM-DNA. Results obtained from both methods were concordant in 183 (82.8%) cases (kappa=0.48). Patients with ICM-DNA diploid gastric cancer survived significantly longer than those with ICM-DNA aneuploid gastric cancer (log rank 10.1, P=0.001). For FCM-DNA data, this difference did not reach statistical significance. The multivariate Cox model showed that ICM-DNA ploidy status predicted patient survival independently of tumour-node-metastasis status. CONCLUSION: ICM-DNA ploidy status is an independent predictor of survival in gastric cancer patients and may therefore be a more clinically relevant read out of gross genomic damage than FCM-DNA.

DNA copy number profiles of primary tumors as predictors of response to chemotherapy in advanced colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is biologically a heterogeneous disease, which may affect response to drug therapy. We investigated the correlation of genome-wide DNA copy number profiles of primary tumors with response to systemic chemotherapy in advanced CRC. PATIENTS AND METHODS: DNA was isolated from formaldehyde-fixed paraffin-embedded primary tumors of 32 patients with advanced CRC, which were selected based on either a good response (n = 16) or a poor response (n = 16) to first-line combination therapy with capecitabine and irinotecan. High-resolution DNA copy number profiles were obtained by means of 30 K oligonucleotide-based array comparative genomic hybridization (aCGH). RESULTS: Unsupervised hierarchical cluster analysis of the aCGH data revealed two clusters of 19 and 13 tumors, respectively, and cluster membership showed a significant correlation with response status (P < 0.03). The nonresponders had fewer chromosomal alterations compared with the responders, in particular less losses were found (P < 0.03). Most prominent differences between the two groups were losses of regions 18p11.32-q11.2 (P < 0.02) and 18q12.1-q23 (P < 0.03), which were more frequently observed in responders. CONCLUSIONS: Differences in DNA copy number profiles of primary CRCs are associated with response to systemic combination chemotherapy with capecitabine and irinotecan. Responders overall had more chromosomal alterations, especially loss of chromosome 18.

MAL promoter hypermethylation as a novel prognostic marker in gastric cancer.

T-lymphocyte maturation associated protein, MAL, has been described as a tumour-suppressor gene with diagnostic value in colorectal and oesophageal cancers, and can be inactivated by promoter hypermethylation. The aim of this study was to analyse the prevalence of MAL promoter hypermethylation and the association with mRNA expression in gastric cancers and to correlate methylation status to clinicopathological data. Bisulphite-treated DNA isolated from formalin-fixed and paraffin-embedded samples of 202 gastric adenocarcinomas and 22 normal gastric mucosae was subjected to real-time methylation-specific PCR (Q-MSP). Two regions within the MAL promoter (M1 and M2) were analysed. In addition, 17 frozen gastric carcinomas and two gastric cancer cell lines were analysed both by Q-MSP and real-time RT-PCR. Methylation of M1 and M2 occurred in 71 and 80% of the gastric cancers, respectively, but not in normal gastric mucosa tissue. Hypermethylation of M2, but not M1, correlated with significantly better disease-free survival in a univariate (P=0.03) and multivariate analysis (P=0.03) and with downregulation of expression (P=0.01). These results indicate that MAL has a putative tumour-suppressor gene function in gastric cancer, and detection of promoter hypermethylation may be useful as a prognostic marker.

Gastric cancers in young and elderly patients show different genomic profiles.

Although most gastric cancers occur in elderly patients, a substantial number of cases of this common disease occur in young patients. Gastric cancer is a heterogeneous disease at the genomic level and different patterns of DNA copy number alterations are associated with different clinical behaviour. The aim of the present study was to explore differences in DNA copy number alterations in relation to age of onset of gastric cancer. DNA isolated from 46 paraffin-embedded gastric cancer tissue samples from 17 patients less than 50 years of age [median 43 (21-49) years] and 29 patients greater than or equal to 70 years of age [median 75 (70-83) years] was analysed by genome-wide microarray comparative genomic hybridization (array CGH) using an array of 5000 BAC clones. Patterns of DNA copy number aberrations were analysed by hierarchical cluster analysis of the mode-normalized and smoothed log(2) ratios of tumour to normal reference fluorescence signal intensities using TMEV software, after which cluster membership was correlated with age group. In addition, supervised analysis was performed using CGH Multi-array. Hierarchical cluster analysis of the array CGH data revealed three clusters with different genomic profiles that correlated significantly with age (p = 0.006). Cluster 1 mainly contained young patients, while elderly patients were divided over clusters 2 and 3. Chromosome regions 11q23.3 and 19p13.3 contributed most to age-related differences in tumour profiles. Gastric cancers of young and old patients belong to groups with different genomic profiles, which likely reflect different pathogenic mechanisms of the disease.

Reduced-intensity conditioning regimens in malignant haematological diseases.

Allogeneic stem cell transplantation is a potentially curative procedure for patients with haematological malignancies. Conventional, myeloablative conditioning is, however, poorly tolerated by patients of advanced age, those receiving second transplants and those with concomitant diseases. Based on recognition of the importance of a graft-versus-disease (GVD) effect in curing malignant haematological disease, reduced intensity conditioning (RIC) as preparation for allogeneic stem cell transplantation has been developed for these patients. Although large prospective randomised clinical trials with significant follow-up are lacking, transplant-related morbidity and mortality of RIC transplants seem to compare favourably with conventional conditioning in this group of patients.

DNA copy number changes at 8q11-24 in metastasized colorectal cancer.

BACKGROUND: C-Myc, a well-known oncogene located on 8q24.12-q24.23, is often amplified and over-expressed in both primary and metastasizing colorectal cancer. In addition, PRL-3 (also known as PTP4A3), a tyrosine phosphatase located on 8q24.3, is amplified in colorectal cancer metastasis. Beside PRL-3 and c-myc, other oncogenes located on the 8q23-24 region might be involved in this process. Therefore, the present study aims to correlate DNA copy number status of a series of genes at 8q23-24 in colorectal cancer at high resolution in correlation to metastatic disease. MATERIALS AND METHODS: Thirty-two cases of colorectal cancer, 10 stage B1, 10 B2 and 12 D (Astler-Coller) with their corresponding liver metastasis and one colorectal cell line (colo205, previously analyzed by array-CGH), were included in this study. A chromosome 8 specific MLPA probe mixture was used to analyze the presence of DNA copy number changes. The probe mixture contained 29 probes covering 25 genes on chromosome 8, as well as 6 control probes on other chromosomes. RESULTS AND DISCUSSION: MLPA results obtained of the colo205 colorectal cell line were comparable with previous array-CGH results, thus validating the MLPA probe mixture. Astler-Coller B1 and B2 colorectal cancers differed significantly in DNA copy number of the genes, MOS (p=0.04), MYC (p=0.007), DDEF1 (p=0.004), PTK2 (p=0.02) and PTP4A3 (p=0.04). When comparing these with Astler-Coller D primary tumors, significant differences were seen for several genes as well (MYC (p<0.000), DDEF1 (p<0.000), SLA (p<0.000), PTK2 (p<0.000), PTP4A3 (p=0.002), and RECQL4 (p=0.01)). When comparing primary Astler-Coller D tumors and their corresponding liver metastases, a similar pattern of gains and losses was observed. Most of the liver metastases showed higher DNA copy number ratios than the corresponding primary tumors, but this difference was only significant for TPD52 (p=0.02) and EIF3S6 (p=0.007). CONCLUSION: In addition to c-myc, multiple genes on chromosome 8 differed significantly between primary colorectal cancers with and without liver metastases. This observation is consistent with the concept that clinical behaviour, like risk of liver metastasis, is determined by the genomic profile that is already present in the primary tumor.