Impact of the COVID-19 pandemic in the early-onset colorectal cancer

The COVID19 pandemic has affected the spectrum of cancer care worldwide. Early onset colorectal cancer (EOCRC) is defined as diagnosis below the age of 50. Patients with EOCRC faced multiple challenges during the COVID19 pandemic and in some institutions it jeopardized cancer diagnosis and care delivery. Our study aims to identify the clinicopathological features and outcomes of patients with EOCRC in our Centre during the first wave of the pandemic in comparison with the same period in 2019 and 2021.

Patients with EOCRC visited for the first time at Vall d'Hebron University Hospital in Spain from the 1st March to 31st August of 2019, 2020 and 2021 were included in the analysis. 177 patients with EOCRC were visited for the first time between 2019 and 2021, of which 90 patients met the inclusion criteria (2019: 30 patients, 2020: 29 patients, 2021: 31 patients). Neither differences in frequency nor in stage at diagnosis or at first visit during the given periods were observed. Of note, indication of systemic therapy in the adjuvant or metastatic setting was not altered. Days to treatment initiation and enrollment in clinical trials in this subpopulation was not affected due to the COVID-19 outbreak.

Plasmatic BRAF-V600E allele fraction as a prognostic factor in metastatic colorectal cancer treated with BRAF combinatorial treatments

BACKGROUND

Combination of a BRAF inhibitor (BRAFi) and an anti-epidermal growth factor receptor (EGFR), with or without a MEK inhibitor (MEKi), improves survival in BRAF-V600E-mutant metastatic colorectal cancer (mCRC) over standard chemotherapy. However, responses are heterogeneous and there are no available biomarkers to assess patient prognosis or guide doublet- or triplet-based regimens. In order to better characterize the clinical heterogeneity observed, we assessed the prognostic and predictive role of the plasmatic BRAF allele fraction (AF) for these combinations.

PATIENTS AND METHODS

A prospective discovery cohort including 47 BRAF-V600E-mutant patients treated with BRAFi-anti-EGFR ± MEKi in clinical trials and real-world practice was evaluated. Results were validated in an independent multicenter cohort (n= 29). Plasmatic BRAF-V600E AF cut-off at baseline was defined in the discovery cohort with droplet digital PCR (ddPCR). All patients had tissue-confirmed BRAF-V600E mutations.

RESULTS

Patients with high AF have major frequency of liver metastases and more metastatic sites. In the discovery cohort, median progression-free survival (PFS) and overall survival (OS) were 4.4 and 10.1 months, respectively. Patients with high BRAF AF (≥2%, n = 23) showed worse PFS [hazard ratio (HR) 2.97, 95% confidence interval (CI) 1.55-5.69; P = 0.001] and worse OS (HR 3.28, 95% CI 1.58-6.81; P = 0.001) than low-BRAF AF patients (<2%, n = 24). In the multivariable analysis, BRAF AF levels maintained independent significance. In the validation cohort, high BRAF AF was associated with worse PFS (HR 3.83, 95% CI 1.60-9.17; P = 0.002) and a trend toward worse OS was observed (HR 1.86, 95% CI 0.80-4.34; P = 0.15). An exploratory analysis of predictive value showed that high-BRAF AF patients (n = 35) benefited more from triplet therapy than low-BRAF AF patients (n = 41; PFS and OS interaction tests, P < 0.01).

CONCLUSIONS

Plasmatic BRAF AF determined by ddPCR is a reliable surrogate of tumor burden and aggressiveness in BRAF-V600E-mutant mCRC treated with a BRAFi plus an anti-EGFR with or without a MEKi and identifies patients who may benefit from treatment intensification. Our results warrant further validation of plasmatic BRAF AF to refine clinical stratification and guide treatment strategies.

Identification and external validation of clinical-molecular features to predict benefit from oxaliplatin reintroduction/rechallenge in patients with refractory metastatic colorectal cancer (mCRC)

153

Background: Oxaliplatin is a backbone cytotoxic treatment for mCRC patients, particularly in the front-line setting. In the refractory disease, current treatment options are scarce and with limited efficacy. Several retrospective studies have explored the efficacy of oxaliplatin reintroduction/rechallenge (OxRe) in this scenario. However, more evidence is still needed to determine which patients do benefit from this treatment strategy. Methods: The discovery cohort includes all patients treated with oxaliplatin in a third- or fourth-line setting at VHIO between 2015 and 2021 (N = 102). Results were externally validated in a real-world cohort of patients treated at community oncology practices from Oncoclínicas Group in Brazil (N = 157). We analyzed the impact of clinical-molecular features in uni- and multivariable prognostic models in terms of median progression free survival (mPFS) (discovery cohort) and median time to treatment discontinuation (mTTD) (validation cohort). For both cohorts separately, data was extracted from EHRs in structured formats (demographics, tumor characteristics, pharmacy records) and combined with elements from unstructured sources (physician notes on progression and survival status) using technology-based abstraction techniques. Results: In the discovery cohort, 102 out of 735 mCRC patients (13,9%) were eligible. Median oxaliplatin-free interval (from Oxl stop to OxRe) was 17 months (CI95% 13.0-23.2). In OxRe setting, mPFS was 4.0 months (CI95% 3.29-5.03). In PFS multivariate analysis, determinants of favorable outcome were left tumor location (p = 0.01), oxaliplatin-free interval (p = 0.03), administration of Bev in refractory setting (p = 0.001), and not receiving Bev in first-line treatment (p = 0.008). Overall, 27% of all patients had a mPFS > 6 months with OxRe. In the validation cohort, out of 4,317 patients with mCRC, 157 (4%) were treated with OxRe. Median oxaliplatin-free interval was 15 months. Median time to treatment discontinuation (mTTD) of the OxRe was 3.4 months (CI95% 2.8-4.2). In multivariable model, the only independent prognostic factor was addition of Bev to OxRe (p = 0.036). Interestingly, 31% of all patients had mTTD > 6 months, largely enriched (65%) in patients with first Bev exposure at the time of OxRe. Conclusions: This study suggests that in refractory mCRC patients re-exposed to oxaliplatin-based chemotherapy, the addition of Bev is associated with improved outcomes. One-third of the patients are long-term responders (PFS/TTD > 6 months), reinforcing the value of this strategy in selected populations and the relevance of anti-angiogenic agents in refractory mCRC.

A Comprehensive Biomarker Analysis of Microsatellite Unstable/Mismatch Repair Deficient Colorectal Cancer Cohort Treated with Immunotherapy

The search for immunotherapy biomarkers in Microsatellite Instability High/Deficient Mismatch Repair system (MSI-H/dMMR) metastatic colorectal cancer (mCRC) is an unmet need. Sixteen patients with mCRC and MSI-H/dMMR (determined by either immunohistochemistry or polymerase chain reaction) treated with PD-1/PD-L1 inhibitors at our institution were included. According to whether the progression-free survival with PD-1/PD-L1 inhibitors was longer than 6 months or shorter, patients were clustered into the IT-responder group (n: 9 patients) or IT-resistant group (n: 7 patients), respectively. In order to evaluate determinants of benefit with PD-1/PD-L1 inhibitors, we performed multimodal analysis including genomics (through NGS panel tumour-only with 431 genes) and the immune microenvironment (using CD3, CD8, FOXP3 and PD-L1 antibodies). The following mutations were more frequent in IT-resistant compared with IT-responder groups: B2M (4/7 versus 2/9), CTNNB1 (2/7 versus 0/9), and biallelic PTEN (3/7 versus 1/9). Biallelic ARID1A mutations were found exclusively in the IT-responder group (4/9 patients). Tumour mutational burden did not correlate with immunotherapy benefit, neither the rate of indels in homopolymeric regions. Of note, biallelic ARID1A mutated tumours had the highest immune infiltration and PD-L1 scores, contrary to tumours with CTNNB1 mutation. Immune microenvironment analysis showed higher densities of different T cell subpopulations and PD-L1 expression in IT-responders. Misdiagnosis of MSI-H/dMMR inferred by discordances between immunohistochemistry and polymerase chain reaction was only found in the IT-resistant population (3/7 patients). Biallelic ARID1A mutations and Wnt signalling activation through CTNNB1 mutation were associated with high and low T cell immune infiltrates, respectively, and deserve special attention as determinants of response to PD-1/PD-L1 inhibitors. The non-MSI-H phenotype in dMMR is associated with poor benefit to immunotherapy. Our results suggest that mechanisms of resistance to immunotherapy are multi-factorial.

RNF43 mutations predict response to anti-BRAF/EGFR combinatory therapies in BRAFV600E metastatic colorectal cancer

Anti-BRAF/EGFR therapy was recently approved for the treatment of metastatic BRAF^V600E colorectal cancer (mCRC^BRAF-V600E). However, a large fraction of patients do not respond, underscoring the need to identify molecular determinants of treatment response. Using whole-exome sequencing in a discovery cohort of patients with mCRC^BRAF-V600E treated with anti-BRAF/EGFR therapy, we found that inactivating mutations in RNF43, a negative regulator of WNT, predict improved response rates and survival outcomes in patients with microsatellite-stable (MSS) tumors. Analysis of an independent validation cohort confirmed the relevance of RNF43 mutations to predicting clinical benefit (72.7% versus 30.8%; P = 0.03), as well as longer progression-free survival (hazard ratio (HR), 0.30; 95% confidence interval (CI), 0.12–0.75; P = 0.01) and overall survival (HR, 0.26; 95% CI, 0.10–0.71; P = 0.008), in patients with MSS-RNF43^mutated versus MSS-RNF43^wild-type tumors. Microsatellite-instable tumors invariably carried a wild-type-like RNF43 genotype encoding p.G659fs and presented an intermediate response profile. We found no association of RNF43 mutations with patient outcomes in a control cohort of patients with MSS-mCRC^BRAF-V600E tumors not exposed to anti-BRAF targeted therapies. Overall, our findings suggest a cross-talk between the MAPK and WNT pathways that may modulate the antitumor activity of anti-BRAF/EGFR therapy and uncover predictive biomarkers to optimize the clinical management of these patients.

The presence of inactivating mutations in RNF43, a negative regulator of WNT, in tumor cells predicts improved response rates and survival outcomes in patients with metastatic BRAF^V600E colorectal cancer treated with anti-BRAF/EGFR therapy.

Molecular characterization and subsequent treatments after encorafenib-cetuximab +/- binimetinib in BRAF V600E-mutated colorectal cancer

3562

Background: The BRAF-V600E mutation confers poor prognosis in patients with mCRC. E-C+/-B improve clinical outcomes compared with standard of care. Data about subsequent treatment lines and the impact of NGS in the treatment choice after the BRAF targeted treatment are still limited. We have analyzed the global overall survival (OS) and the impact of NGS to guide subsequent treatments (approved targeted therapies (TT) or clinical trials (CT)) after E-C+/-B. Methods: Patients who had received E-C+/-B were included. Clinical data was collected prospectively. Tissue NGS was performed prospectively and retrospectively using an in-house NGS panel (VHIO-300). Subsequent treatments’ clinical outcomes were described. Percentage of patients who received TT or CT based on NGS results is reported. Clinical outcomes were calculated using survival Kaplan-Meier curves. Results: From 2017 to 2021, 59 patients with refractory mCRC received E-C+/-B at our institution. 50 patients have already progressed to the BRAF inhibitor combination and 9 patients remain on BRAF inhibitor treatment. Tumor tissue for NGS testing before BRAF inhibitor treatment was available in 70% of patients (41/59). BRAF-V600E mutation was confirmed in tissue using ddPCR in all patients. The most frequent alterations were: BRAF-V600E 93%, TP53 64%, RNF43 30%, APC 20%, PIK3CA 14%, NOTCH1/2 9%, RANBP2 8%, PTEN 8%, MET amplification 5%. MSI incidence was 10%, 2 out of 6 (33%) received subsequent immunotherapy. After the BRAF inhibitor combination, 23 patients (38%) did not receive subsequent treatment (clinical deterioration or death). The 27 remaining patients (62%) received 41 subsequent treatments (37% of them were TT or CT). Median subsequent lines after the BRAF inhibitor combination were 1 (0-3). NGS led to targeted therapy in 20% of the patients: BRAF inhibitors combos (20%), microtubule inhibitors (13%), antiPD1 (13%), NOTCH inhibitors (6%), and MET inhibitor (6%). ORR among patients who received matched TT or CT was 6% and DCR (CR+PR+SD) was 47%. The median OS after the BRAF inhibitor was 3.8 months; 10.1 months vs 3.0 months (HR 0.43 (95%CI 0.2-0.95), p = 0.04) for those patients who received TT or CT vs patients who did not receive TT or CT. When MSI patients were excluded mOS was 5.2 vs 3.0 months (HR 0.61 (95%CI 0.27-1.37), p = 0.23) respectively. There were no differences in terms of OS regarding the number of previous lines (0-1 vs 2-3, HR 0.75 (95%CI 0.4-1.42), p = 0.37) or with the BRAF inhibitor regimen used (E-C vs E-C-B) (HR 0.84, (95%CI 0.44-1.6), p = 0.61) Conclusions: This study suggests that patients with BRAF-V600E mutant mCRC could have benefit when treated with TT and/or in CT after a BRAF inhibitor-based therapy, including immunotherapy. Genomic analysis might help to guide subsequent treatments. Because of molecular heterogeneity, these patients should be discussed in Molecular Tumor Boards.

Impact of circulating tumor DNA (ctDNA) mutant allele fraction in response to anti-angiogenic therapy in RAS-mutant metastatic colorectal cancer (mCRC): Clinical data in the first-line setting and correlation in patient-derived xenograft (PDX) models

3560

Background: Currently, there are no well-established biomarkers available to select mCRC patients (pts) who will benefit most from antiangiogenic therapy. RAS mutant (mt) allele fraction in plasma (plMAF) is an independent prognostic factor in mCRC. Preliminary data from our group suggests the possible predictive role of plMAF in RAS mt pts treated with 1st line chemotherapy (ct) +/- bevacizumab (bev). Methods: Data prospectively/retrospectively collected from RASmt mCRC pts who received 1st line ct+/-bev treatment in our center, selecting the subset of pts with plMAF sample evaluable with digital PCR (BEAMing) at baseline. Pts were stratified as high (≥ 5.8%) or low ( < 5.8%) plMAF, based on a previously established prognostic cutoff (Elez et al, Mol Onc 2019). We investigated the associations between clinic-pathological variables, overall survival (OS), and progression-free survival (PFS) stratified by plMAF RAS levels using Cox regression models. OS and PFS were calculated by Kaplan-Meier method. Murine PDX were developed from mCRC pts including models from patients with KRASG12/G13 mutations to explore recapitulation of the clinical findings. Results: From October ‘17 to December ‘21, 102 basal plasma samples were analyzed by BEAMing. 47 pts (46%) were classified as high, 39 pts (38%) as low, and 16 (16%) as no-mt detected by BEAMing (non-shedding). OS was significant longer in low plMAF pts than in high plMAF pts (median OS 15.9 vs 37.1 months (mo); HR 0.43; p = 0.001). In high plMAF pts, a trend towards a better PFS was observed in those pts treated with ct+bev compared to ct alone (median 9.4 vs 6.1 mo; HR 0.6; p = 0.18). No differences were observed in low plMAF pts treated with ct +/- bev (median 14.5 vs 14.9 mo; HR 1.2; p = 0.58). Results were not modified when adjusted by the presence of liver metastases. The multivariate PFS model showed no association between RAS plMAF and clinicopathological variables, except for treatment benefit with ct+bev and better outcomes in pts with resectable liver metastases. Interestingly, human ctDNA in one murine PDX model from non-shedding pt was not detectable, whereas human ctDNA was present in another PDX model with a plMAF of 36.2%. Conclusions: This study suggests that plMAF could be a promising predictive biomarker of response to bev in 1st line RASmt mCRC, but more pts need to be analyzed to confirm this effect. Our results confirm the prognostic role of RASmt plMAF in mCRC. plMAF could partially depend on tumor cell shedding degree and characteristics on the tumor vasculature architecture, this is being investigated in ongoing imaging studies and PDX models. These models will also help to understand the biology behind tumor response to bev and its connection with ctDNA shedding.

Young-onset colorectal cancer: A call for action

10563

Background: Young-onset colorectal cancer (YOCR) is defined as diagnosis below the age of 50. Over the past decades, the incidence of YOCRC has increased at an alarming rate, but causes and pathogenesis still remain unknown. Early detection of colorectal cancer (CRC) has demonstrated to improve survival. Despite these facts, adults < 50 years old are not yet included in screening programs and YOCRC is not well characterized. We aimed to characterize the clinical and molecular characteristics of YOCRC in patients (pts) diagnosed at our institution. Methods: Consecutive pts with a diagnosis of CRC below the age of 50 visited for the first time at Vall d’Hebron University Hospital in Spain between January 2017 and October 2020 were included in the analysis. Data of clinicopathologic features and treatment were collected retrospectively from medical records. Results: 205 pts met the inclusion criteria, 111 (54%) were females, 8 (4%) presented a personal history of cancer at diagnosis and 109 (53%) a family history of cancer. Age at diagnosis was: < 30: 10 (5%), {30 – 40): 52 (25%), {40-45): 51 (25%), {45-50): 92 (45%). Site of primary tumor was: right colon: 50 (24%), left colon: 107 (52%): rectum: 48 (24%). Stage at diagnosis was I: 3 (1%), II: 14 (7%), III: 60 (29%), IV: 128 (63%). 6 of 14 (43%) and 44 of 60 patients (73%) with stage II and III CRC presented disease progression after initial treatment, respectively. Molecular status was: KRAS mutation: 74 (36%), NRAS mutation: 7 (3%), BRAF mutation: 12 (6%), MSI-H: 12 (6%). 43 pts (21%) had documentation of genetic counseling. Median (range) number of lines of treatment for metastatic disease was 3 (1-7), 53 pts (30%) received at least 4 lines of treatment. Median (range) number of metastatic sites was: 2 (1-6). 114 patients (55.6%) had died at the cut-off timepoint. Conclusions: YOCR is usually diagnosed with a more advanced stage than standard-onset CRC, with a poorer course of the disease. Further studies in young adults with CRC should address this phenomenon to understand the underlying causes, and prioritize genetic counseling. Our results support the unmet need of initiating screening programs in adults younger than 50 years, the urgency for a global consensus and a call for action.

Fusobacterium nucleatum persistence and risk of recurrence after preoperative treatment in locally advanced rectal cancer

BACKGROUND

Accumulating evidence has identified Fusobacterium as an important pathogenic gut bacterium associated with colorectal cancer. Nevertheless, only limited data exist about the role of this bacterium in locally advanced rectal cancer (LARC). In this study, we quantified Fusobacterium nucleatum in untreated and post-neoadjuvant chemoradiotherapy (nCRT) samples from LARC patients and investigated its association with therapy response and survival.

PATIENTS AND METHODS

A total of 254 samples from 143 patients with rectal adenocarcinomas were analyzed for the presence and abundance of F. nucleatum using RNA in situ hybridization and digital image analysis. Assay accuracy was determined using infected cell lines and tumor samples with available quantitative PCR data. We studied the impact of F. nucleatum load on pathologic complete response and relapse-free survival. Treatment-induced changes were evaluated in paired pre- and post-nCRT samples (n = 71). Finally, tumor microenvironment changes during nCRT were assessed in paired samples (n = 45) by immune contexture analysis.

RESULTS

F. nucleatum tissue levels by RNA in situ hybridization strongly correlated with quantitative PCR (r = 0.804, P < 0.001). F. nucleatum abundance was higher in untreated [median, 7.4; 95% confidence interval (3.7-16.2)] compared with treated [median, 1.6; 95% confidence interval (1.3-2.4)] tumors (P <0.001) with 58% (73/126) and 26% (22/85) positive tumors, respectively (P < 0.001). Baseline F. nucleatum levels were not associated with pathologic complete response. F. nucleatum positivity after nCRT, but not baseline status, significantly increased risk of relapse [hazard ratio = 7.5, 95% confidence interval (3.0-19.0); P < 0.001]. Tumors that turned F. nucleatum-negative after nCRT had a strong increase in CD8+ T cells post-nCRT (P < 0.001), while those that persisted F. nucleatum-positive after nCRT lacked CD8+ T cells induction in post-nCRT samples compared with baseline (P = 0.69).

CONCLUSION

F. nucleatum persistence post-nCRT is associated with high relapse rates in LARC, potentially linked to suppression of immune cytotoxicity.

Patient and tumor characteristics as determinants of overall survival (OS) in BRAF V600 mutant (mt) metastatic colorectal cancer (mCRC) treated with doublet or triplet targeted therapy

4112

Background: BRAF V600 mt mCRC is an aggressive disease with poor OS under standard chemotherapy. Treatment with doublet and triplet targeted combinations, such as BRAF inhibitor+ antiEGFR+/- MEK inhibitor, has been shown to improve outcomes. Prognostic factors in this targeted treated population remain to be studied. Methods: Prospective international cohort of patients who received doublet or triplet anti-BRAF combinations in clinical trials or as compassionate use. Univariate Cox models for OS were constructed and the strongest predictors in stepwise variable selection were used to develop a prognostic score. The final multivariate model with selected predictors was stratified by prior lines. Results: In total, 42 patients were enrolled. Median age 60.7 y (33-83), 61% female, 61% right-sided tumors, 26% received 2 or more prior chemotherapy lines. One patient (2.6%) achieved complete response and 36% had partial response with median follow-up of 14.3 months. Median progression-free survival was 5.5 months (CI95% 4.4-10.4) and median OS (mOS) was 10.7 months (CI95% 8.4-22.1). In univariate models, ECOG performance status (1 vs 0), CEA levels (high - > 3.5 ng/mL- vs low - < 3.5 ng/mL), CA 19.9 (high vs. low), LDH (high vs. low), number of metastatic sites and presence of liver metastasis were significant prognostic factors. On the other hand, MSI status and peritoneal or nodal metastasis did not associate with outcome. In multivariable model, strongest determinants of OS were ECOG and baseline CEA levels. If high-risk for both factors (ECOG 1 and CEA high, 46% of the patients), mOS was 5.6 months (CI95% 4.2-NA); if intermediate-risk (either ECOG 1 or CEA high, 33%), mOS was 13.5 months (CI95% 10.6-NA); if low-risk (ECOG 0 and CEA low, 21%), mOS not reached (CI95% 16.5-NA). Differences between intermediate- and high-risk prognostic groups compared to low-risk were significant (HR = 5.9, p = 0.03; and HR = 25.9, p < 0.001, respectively). Conclusions: Patients characteristics such as ECOG and surrogates of tumor burden like CEA levels remain important OS determinants in BRAF V600 mt mCRC treated with doublet or triplet targeted therapy. In fact, there are not prognostic scores regarding BRAF mt mCRC treated with targeted therapies. Our study suggests that these prognostic factors may be considered as stratification factors in future clinical trials.

The predictive role of plasma mutant allele fraction to antiangiogenic drugs in patients with mCRC: An expanded analysis of surrogate biomarkers of response to first-line treatment with bevacizumab

3541

Background: So far, no biomarkers of response to anti-angiogenic drugs are available in colorectal cancer (CRC) treatment. Liquid biopsy tracks dynamic mutational changes in CRC patients (pts). RAS mutant allele fraction in plasma (plMAF) is an independent prognostic marker in metastatic CRC (mCRC). We explored the predictive value of plMAF in RAS mutant pts treated in 1st line with chemotherapy +/- bevacizumab (bev). Methods: A multicentric prospective/retrospective analysis was conducted. We collected data from 226 mCRC pts and selected the subset not eligible for metastasis resection with basal plMAF sample evaluable for RAS mutant MAF quantification with digital PCR (BEAMing). Pts were stratified as high (≥ 5.8%) or low ( < 5.8%) plMAF. We investigated associations between clinicopathological variables and progression-free survival (PFS) stratified by plMAF RAS levels using Cox regression models and survival data were calculated by Kaplan-Meier method. Computational analysis of baseline CT scan data extracted 93 radiomics features of all the lesions per patient including 1) 1st class from density histogram distribution and texture analysis by 2) 2nd order and 3) higher order feature classes. The radiomic features distribution between pts with high and low pIMAF was assessed with Student’s t-test analysis. Results: From October 17 to May 19, 63 basal plasma samples were analysed with BEAMing. 42 pts (67.7%) were classified as high and 21 pts (32,3%) as low plMAF. In high plMAF subgroup, a statistically significant longer PFS favouring FOLFOX+bev was observed, compared to FOLFOX alone (10.7 vs 6.9 mts; HR: 0.30; p = 0.002). In low RAS plMAF subgroup, no differences in terms of PFS were observed in either arm (8.9 vs 8.7 mts; HR: 0.7; p = 0.6). Multivariate PFS model showed no association between RAS plMAF and clinicopathological variables, except for high RAS plMAF and treatment benefit with FOLFOX+bev. The CT-radiomics signature, that may translate tumor vascularization, differentiated patients with high vs low pIMAF (p = 0.002). 58 patients (92%) had similar radiomic score; 5 patients with high plMAF (8%) presented very heterogeneous radiomic score distribution. Conclusions: Tumor-borne RAS plMAFs may constitute a potential predictive biomarker of efficacy for anti-angiogenic drugs in mCRC. Next steps will include the identification of -histological, transcriptomic and radiomic- surrogate biomarkers of response that reflect tumor irrigational status.

Mortality of women with ductal carcinoma in situ of the breast: a population-based study from the Girona province, Spain (1994-2013)

PURPOSE

We aim to comprehensively describe the incidence and mortality trends of ductal carcinoma in situ (DCIS) in the Girona province, Spain (1994-2013) and to estimate the all-cause mortality excess risk of diagnosed women.

METHODS

Age-standardized rates of DCIS were estimated between 1994 and 2013. Standard mortality ratios (SMR) and absolute excess mortality were calculated overall and by tumor and patient characteristics. A sensitivity analysis was conducted excluding cases with a subsequent invasive breast cancer (sIBC).

RESULTS

Of the 641 women included, 56 died (follow-up time: 8.4 person-years). Between 1994 and 2013, a significant increase in incidence and decrease in mortality was identified among women aged between 50 and 69 years old. Neoplasms and circulatory system disease were the most common causes of death. No excess risk of death was found overall, except for women aged < 50 years (SMR = 3.44, 95% CI 1.85; 6.40) and those with a sIBC (SMR = 2.51, 95% CI 1.26; 5.02), risk that lessened when cases with sIBC were excluded. Patients with sIBC also showed an excess risk (SMR = 2.29, 95% CI 1.03; 5.10).

CONCLUSIONS

Among women aged 50-69 years old, incidence of DCIS has significantly increased yet mortality has decreased. Overall, the all-cause mortality risk of women diagnosed with DCIS remains similar to that of the general population except for women diagnosed before age 50 and those with sIBC, who showed a significant increased risk. Differential management of these patients should be considered.

Descriptive epidemiology of primary malignant and non-malignant central nervous tumors in Spain: Results from the Girona Cancer Registry (1994-2013)

BACKGROUND

Systematic registration of non-malignant central nervous system (CNS) tumors is a rare practice among European cancer registries. Thus, the real burden of all CNS tumors across Europe is underestimated. The Girona Cancer Registry provides here the first data on CNS tumor incidence and survival trends in Spain for all histological types, including malignant and non-malignant tumors.

METHODS

Data on all incident cases of primary CNS tumors notified to the Girona population-based cancer registry from 1994 to 2013 (n=2,131) were reviewed. Incidences rates (IRs) were standardized to the 2013 European population and annual percentage changes (EAPC) were estimated using a piecewise log linear model. 1- and 5-year observed (OS) and relative survival (RS) were also calculated. Results were expressed by sex, age-group, histological subtype and behavior.

RESULTS

The overall IR was 16.85 and increased across the period of study (EAPC=+2.2%). The proportion and IRs of malignant (50.2%; IR=9.35) and non-malignant cases (49.8%; IR=9.14) were similar; however, non-malignant tumors were more frequent in women (sex ratio=0.63). The most frequently reported histologies were meningioma (27.6%; IR=5.11) and glioblastoma (22.2%; IR=4.15), which also accounted for the highest and lowest 5-year RS (80.2%; 3.7%, respectively). Globally, 5-year RS was lower in men (42.6% vs. 58.3%, respectively) and in the elderly (64.9% for 0-14years vs. 23.0% for >74years).

CONCLUSION

This study presents a comprehensive overview of the epidemiology of malignant and non-malignant CNS primary tumors from the well-established region-wide Girona Cancer Registry (1994-2013). Incidence rates were recovered for all histologies. Survival is still dramatically associated to both age and histological subtype.