Sidedness in metastatic colorectal carcinoma: Which are the factors which influence the prognosis?

497

Background: Recent reports demonstrate prognostic and predictive impacts of the location of the primary tumor in metastatic colorectal cancer (mCRC). Our retrospective analysis aimed to determine the influence of primary site on metastatic distribution and disease evolution. Methods: From our database all patients (pts) with mCRC (except transverse carcinoma) treated from 1/12/2007 to 1/12/2016 in our institution were collected. Univariate and multivariate analyses were performed to identify predictors of overall survival (OS). Results: A total of 284 pts with available data were analyzed: 83 with Right-sided Colon Cancer (RCC) (29%), 123 with Left-sided Colon Cancer (LCC) (43%) and 78pts with Rectal Cancer (RC) (28%). Hepatic, lung, lymph nodes and peritoneal metastases were respectively found in 63%, 36%, 23% and 20% of the population. The incidence or number of liver metastases were not influenced by sidedness (p = 0.06), LCC presented more bilobar involvement compared to RCC and RC (p = 0.017). Peritoneal carcinomatosis was significantly correlated to colon cancer (p = 0.002), whereas lung metastases were more common in RC (p < 0.001). Patients with RCC more often presented distal lymph node involvement (p = 0.008). RAS mutation status was known for 241pts (80%), of those 110 (37%) were RAS mutated with no significant differences between RCC, LCC and RC (p = 0.4), BRAF mutation (p = 0.007) was more common in RCC. On a multivariable analysis, primary tumor resection (PTR) and complete response after first line therapy were associated with a better OS but only a trend was observed for LCC and RC. Lung, lymph and peritoneal metastasis were associated with worse OS (Table). Conclusions: These results suggests that mCRC had different clinical presentation at diagnosis, the association with molecular features may explain the independent prognostic factor for OS of the sidedness. [Table: see text]

Association of single nucleotide polymorphisms (SNPs) in CYP17A1 and SLCO2B1 genes and clinical outcome in metastatic castration-resistant prostate cancer patients treated with abiraterone acetate: results of the ABIGENE prospective study

358

Background: Abiraterone acetate (AA), a CYP17A1 inhibitor, has been approved in the treatment of metastatic castration-resistant prostate cancer (mCRPC). Germline polymorphisms in genes involved in androgen biosynthesis or transport may influence response and survival in this setting. Methods: ABIGENE is a multicentric prospective non-randomized pharmacogenetic study (NCT01858441). The primary objective was to investigate the association between 13 SNPs in genes related to AA pharmacology (CYP17A1, SLCO2B1 and SLCO2B3) and radiographic progression-free survival (rPFS), according to PCWG2 criteria, in pts with mCRPC treated with first-line AA + prednisone. The main secondary objectives were to evaluate the impact of these SNPs on radiographic and PSA response, overall survival (OS) and toxicity. SNPs were detected in blood samples before starting AA and analyzed by pyrosequencing or PCR-RFLP methods. Kaplan-Meyer’s curves with log-rank tests and cox regression models were used to identify relationships between SNPs and survival. Chi2 tests and student t-tests were used to identify association with response rate and toxicity. Results: 147 pts in 17 french centers were included between 2013 and 2017. Here are presented the results for the first 109 pts. The median follow-up was 28.7 months. Overall response rate (ORR) was 17%, and 74% pts had stable disease as the best response. Median rPFS was 10.9 months (95% CI 9.2-15.3). One SNP (rs10883782) in CYP17A1 was associated with rPFS on AA therapy (Table). Two other SNPs in CYP17A1 (rs4919683) and SLCO2B1 (rs1077858) were significantly associated with radiographic response. Data on PSA response, OS and toxicity will be presented at the meeting. Conclusions: This is the first prospective dedicated study to show an association between SNPs related to androgen metabolism and clinical outcome in mCRPC treated with AA. Clinical trial information: NCT01858441. [Table: see text]

Clinical utility of colon cancer molecular subtypes: Validation of two main colorectal molecular classifications on the PETACC-8 phase III trial cohort

3509

Background: The molecular subtyping of colon cancers (CC) has been the subject of several recent publications, leading to an international consensus. The clinical relevance of these molecular classifications remains to be evaluated on large prospective patient cohorts using a tool that can be widely used on formalin-fixed paraffin-embedded (FFPE) samples. Methods: We aimed to evaluate the clinical relevance of two molecular subtyping systems, CMS (Guinney et al. 2015) and CCMST (Marisa et al. 2013), on the PETACC-8 cohort, a randomized phase III trial comparing adjuvant FOLFOX with or without cetuximab in patients with stage III CC. For each of these two classification systems, a predictor tool was developed and adapted to FFPE samples. The NanoString nCounter platform was used to screen 196 genes. Predictors were built from 249 frozen tumor samples previously used to build our classification system and 61 new paired FFPE/frozen samples. Both predictors were then applied to 1781 PETACC-8 FFPE samples. Subtypes associations to clinical and molecular features were analyzed. Results: The CMS predictor assigned 297 samples to CMS1 (17%), 585 to CMS2 (34%), 68 to CMS3 (4%) and 770 to CMS4 (45%). CMS were significantly associated with several molecular and clinical features, including MSI status (49% in CMS1, p < 0.001), CIMP status (47% in CMS1, p < 0.001), KRAS mutation (75% in CMS3, p < 0.001), BRAF mutation (34% in CMS1, p < 0.001), tumor location (less proximal tumors in CMS2, p < 0.001), validating the predictor tool developed. The classification was significantly associated to prognosis in multivariate analysis, CMS4 subtype having a shorter overall survival (hazard ratio = 1.7, p= 0.021). A deleterious effect of cetuximab was observed in CMS1 (p < 0.05). Similar results were obtained with the CCMST classification. Conclusions: We validated molecular CC subtyping predictors for both CMS and CCMST classifications on PETACC-8 FFPE samples. The prognostic value of CMS and CCMST classifications was confirmed, stem-like tumors being associated with a poor prognosis. These results pave the avenue for widely use of the CC molecular classification in clinical routine.

Pharmacogenetics revisits bevacizumab in breast cancer patients: An ancillary analysis of the UCBG trial COMET—A French multicentric prospective study from R&D UNICANCER

1079

Background: Bevacizumab (Beva) is no longer unanimously recommended in the management of breast cancer (BC). Given the absence of faithful predictors of Beva treatment outcome, we made the hypothesis that constitutional gene polymorphisms could play a role in this context. We report the pharmacogenetic ancillary study of the prospective COMET trial conducted in advanced BC patients (pts) receiving first-line Beva associated with paclitaxel. Methods: Relevant targeted gene polymorphisms were analyzed (blood) in 203 prospective pts (mean age 55.3, median follow-up 24 months). VEGFA at positions -2578C > A (rs699947), -1498T > C (rs833061), -634G > C (rs2010963), and 936C > T (rs3025039) were analyzed by PCR-RFLP. VEGFR1 319A > C (rs9582036), VEGFR2 at positions 604C > T (rs2071559), 1192C > T (rs2305948), 1416T > A (rs1870377), IL8 251T > A (rs4073), CYP2C8 139C > T (rs1572080), 399T > C (rs10509681) and ABCB1 at positions 1199 C > TA (rs2229109), 2677G > TAC (rs2032582) were analyzed by Mass-Array Agena. ABCB1 1236C > T (rs1128503) and 3435T > C (rs1045642) were analyzed by pyrosequencing. All fitted HWE. Results: Median progression-free survival (PFS) was 10.8 months. VEGFR1 319A allele was associated with longer PFS (p = 0.03). The VEGFA-1498T allele was significantly associated with both longer overall survival (OS) (p = 0.005) and PFS (p = 0.065). The VEGFA -2578C allele was associated with greater OS (p = 0.002) and PFS (p = 0.071). These two VEGFA polymorphisms were in linkage disequilibrium (p < 0.0001). Multivariate Cox analysis showed that VEGFA -2578 (p = 0.001) and VEGFR2 1416 (p = 0.025) were significant predictors of OS: the score of favorable alleles (VEGFA -2575C and VEGFR2 1416T) was highly associated with OS (p = 0.0003), with median survival at 24 months being 30% for score 0 (95%CI 15-61), 65% for score 1 (95%CI 55-75) and 90% for score 2 (95%CI 67-90). Conclusions: Application of an easy-to-perform low-cost genotyping test may identify strong predictors of Beva outcome in metastatic BC pts. In the current era of precision medicine, a pharmacogenetic-based personalized Beva therapy deserves to be prospectively validated in BC pts. Clinical trial information: 2012-A00244-39.

Pharmacogenomic determinants of cetuximab and oxaliplatin pharmacokinetics during combined intravenous cetuximab (IV-Cet) and triplet hepatic artery chronomodulated infusion in patients (pts) with initially unresectable liver metastases from colorectal cancer (uLM-CRC) (EU OPTILIV trial)

e14082

Background: Triplet HAI with IV-Cet achieved 29.7% complete uLM-CRC resections (R0+R1) and an overall median survival (OS) of 25.7 months in previously treated pts. While the high antitumour efficacy of this new regimen involved direct exposure of LM to the HAI drugs and their potentiation by cetuximab, haematological and intestinal toxicities mostly related to systemic exposure (Lévi, Ann Oncol 2016; Clin Pharmacokin 2016). Methods: To identify potential pharmacogenomics (PG) determinants of toxicity-related systemic exposure to the HAI drugs, 207 single nucleotide polymorphisms (SNPs) from 34 pharmacology genes were analysed in blood mononuclear cells (ADME PGx, MassArray platform, Sequenom, USA) from 11 pts undergoing a first course of chronomodulated triplet HAI and iv-CET (Levi et al. Clin Pharmacokinet 2016). Relations between SNPs and main pharmacokinetics parameters and toxicities were determined using ANOVA or Fisher Exact test. Results: Nine toxicity-related polymorphic genes were identified in the 52 pts of the PG study (ASCO, submitted). Here we investigated whether any of these polymorphic genes modified PK in 4F and 7M (33-72 yo) with WHO performance status 0-1. ABCB1 (rs1045642) was the only polymorphic gene that was significantly associated with both pharmacokinetics and toxicity in this study population. Conclusions: ABCB1 polymorphisms might contribute to the systemic hematologic toxicity of the combined IV-HAI regimen through altering cetuximab and oxaliplatin disposition, yet without affecting efficacy. Consideration of ABCB1 polymorphism could help optimize OPTILIV delivery in individual patients. Clinical trial information: NCT00852228. [Table: see text]

Impact of pharmacokinetics (PK) of sunitinib (SU) and its metabolite SU12662 on clinical outcome and toxicity in metastatic renal cell cancer (mRCC) patients

506

Background: Pharmacological activity of SU is usually attributed to SU and its active metabolite SU12662, known to exhibit similar potency in inhibiting tyrosine kinase activity and cellular proliferation in vitro. However, equivalence is not clearly demonstrated towards clinical endpoints. The objective of this phase 2 study was to determine the impact of SU and SU12662 on clinical outcomes and toxicity in mRCC patients (NCT00943839). Methods: Patients with mRCC, eligible for SU in the first line setting, were prospectively included. SU was given orally at 50 mg qd for 4 weeks on/2 weeks off until progression or unacceptable toxicity. Minimal concentration at steady-state (CSSmin) was evaluated by high-performance liquid chromatography at day 28 of each cycle for both SU and SU12662. Data for tumor response, survival, and toxicity were recorded. Kaplan-Meyer’s curves with log-rank tests and cox regression models were used to identify relationships between PK parameters and survival. Chi2 tests and student t-tests were used to identify relationships with toxicity. Results: 41 patients in 7 French centers were included between 2009 and 2012. 16 patients had favourable prognosis, 13 intermediate prognosis, and 1 poor prognosis according to IMDC risk groups (Heng, J Clin Oncol 2009). Median follow-up was 30.6 months. Median progression-free survival (PFS) was 20.2 months and median overall survival (OS) was 39.5 months. Mean CSSmin for SU and SU12662 were 57.2 and 29.8 ng/ml, respectively. CSSmin of SU12662 was independently correlated to poor PFS and OS (p = 0.01 and 0.003 respectively). Patients with a mean CSSmin of SU12662 higher than 42.5 ng/ml had a worse PFS and OS compared to patients with lower concentrations: 5.7 months and 5.7 months versus 20.6 months and 39.5 months (p = 0.01 and 0.002 respectively). High CSSmin of both SU and SU12662 were associated with increased incidence of asthenia (p<0.001). Conclusions: High exposure to SU12662 was associated with poor outcomes and increased asthenia for patients with mRCC treated with SU in the first line setting. It may be related to a higher metabolism and unequal activity between SU and SU12662 in vivo. Clinical trial information: NCT00943839.

Combined abiraterone, salvage prostate bed radiotherapy and LH-RH agonists (CARLHA) in biochemically-relapsing prostate cancer patients following prostatectomy: A phase I study of the GETUG/GEP

45

Background: Salvage radiotherapy (RT) plus 6 months LH-RH therapy (ADT) improves biochemical relapse free survival in men with rising PSA following prostatectomy. Abiraterone acetate (Aa) increases overall survival in metastatic prostate cancer. We aimed to establish the toxicity of adding Aa combined with salvage RT and 6 months goserilin (Gos). Methods: We enrolled pT2-pT4a pN0 prostate cancer patients (pts) with rising PSA (0.2 to <2.0 μg/l) following radical prostatectomy. The primary endpoint was to determine the Maximum Tolerated Dose and recommended dose of Aa during RT plus Gos, two dose levels tested : 1 (750mg) and 2 (1000 mg). Two different schemes were explored: Sheme A: Aa (1000 mg) and predisone (10 mg) were given orally during 1 month to salvage IMRT (66 Gy in 33 fractions). The first day of irradiation, Aa is reduced to level 1 or 2 and 10.8 mg Gos is injected (sc). In sheme B, Gos is injected the first day (1 month before starting RT). Results: We recruited 9 + 9 pts in scheme A and B respectively. In scheme A, Testosterone (Tst) levels declined to castration level (<0.5ng/ml) after 10 days . Two/9 pts did not achieve castration levels at 30 days. Median LH levels increased to 10.4 (D10) and 12.5 IU/l (D20). At dose level 1, 4/9 pts (44%) experienced grade 3 hepatitis, occurring prior to RT or during RT (8 Gy, 36 and 54 Gy). We hypothesized that this unexpected liver toxicity was related to the LH increase during the first month (Aa administration without Gos). Therefore, we modified LH-RH administration (scheme B) and recruited 9 more pts. Tst levels dropped to undetectable at day 6, while median LH levels decreased to 6.1 (D10) and 1.7 IU/l (D20). At dose level 1 (3 + 3 pts), no grade 3 liver toxicity was reported. No other grade 3 toxicity was recorded. At dose level 2, 2/3 pts had grade 3 hepatitis occurring during RT. CYP17 polymorphism did not correlate with liver toxicity. Conclusions: The recommended dose of Aa combined to short-term androgen deprivation and salvage RT is 750 mg. Aa alone did lead to castration levels in 22% of pts.An unexpected high frequency of grade 3 liver toxicity was observed. Clinical trial information: NCT01780220.

Pharmacogenetic study in metastatic colorectal cancer (CRC) patients receiving third-line panitumumab-irinotecan: A GERCOR ancillary study

2537^

Background: Test the predictive value of gene polymorphisms potentially linked to panitumumab and irinotecan pharmacodynamics. Methods: 45 patients with metastatic CRC refractory to standard therapy were enrolled in this ancillary pharmacogenetic study as part of a phase II trial that included 63 patients. Inclusion required wild-type KRAS tumor status (codons 12-13, analyses performed in each center). After inclusion, central KRAS re-assessment was performed (codons 12-13-59-61) and 9 patients over 45 were found to carry a KRAS mutation. Patients received panitumumab (6 mg/kg, day 1) associated with irinotecan (180 mg/m2, day 1), Q2W until disease progression or unacceptable toxicity. Analyzed polymorphisms on blood DNA were : EGFR (CA repeats in intron 1, -216G>T, -191C>A), EGF (61A>G), CCND1 (870A>G), UGT1A1 (*28). Results: Cutaneous toxicity imputable to panitumumab i.e. folliculitis and paronychia was not linked to EGFR, EGF or CCND1 polymorphisms. Diarrhea (12 grade 1, 13 grade 2, 8 grade 3) was linked to CCND1 polymorphism: 22% grade 2-3 in AA patients vs 63% in AG+GG patients (p = 0.007). As expected, neutropenia (6 grade 1, 4 grade 2, 5 grade 3) was more frequent in patients bearing the *28 allele of UGT1A1 gene (33% grade 2-3 vs 5% in *1/*1, p = 0.020). In these 45 patients, response rate, progression-free survival and overall survival (OS) were only significantly related to re-assessed KRAS status. Of note, a tendency for a longer OS was observed in patients bearing the *28 allele of UGT1A1 gene (p = 0.091, analysis adjusted for KRAS). Interestingly, the frequency of KRAS mutation was higher in patients with long CA repeats in EGFR gene intron 1: 54.5% i.e. 6 mutated patients among the 11 patients with both alleles ≥17 vs 10.5% i.e. 2 mutated patients among the 19 patients with intermediary alleles vs. 6.7% i.e. 1 mutated patient among the 15 patients with both alleles <17 (p = 0.004). Conclusions: Present data indicate that A870 allele of CCND1 gene (40% AA patients) may protect from diarrhea induced by panitumumab-irinotecan. Also, these results report an original relationship between EGFR polymorphism in intron 1 and KRAS mutation status that merits further confirmation.

Antibody-dependent cell-mediated cytotoxicity (ADCC) evolution under treatment by cetuximab and links with treatment outcome in colorectal cancer (CRC) patients

2600

Background: ADCC plays a role in antitumor activity of IgG1 mAb by inducing immune cell-mediated lysis of tumor cells. We evaluated ADCC ability before and under cetuximab-based treatment and examined its impact on treatment outcome. Methods: 29 patients (17 men, 12 women, median age 72, range 51-84) with metastatic wild-type KRAS CRC treated with chemotherapy (irinotecan or Folfiri) plus cetuximab were prospectively enrolled. ADCC ex-vivo was measured before starting treatment and every 2 months during treatment (1 to 7 measurements/patient, 12 patients with >2 measurements). 400 000 purified Natural Killer cells (CD3- CD56+) from patients were incubated with 10 000 target cells (CAL166 cancer cell line expressing EGFR) and 10 µg/ml cetuximab (triplicates). Cytotoxicity was measured by the LDH-release assay. ADCC was expressed as the % of lyzed target cells. Gene polymorphisms of Fcγ receptors FCGR2a (131Arg>His) and FCGR3a (158Phe>Val) were analyzed (Allelic Discrimination assay). Results: The feasibility rate of ADCC measurement was 88%. ADCC basal values ranged between 30% and 100% (mean 62%, median 66%). Basal ADCC was not influenced by patient gender. A tendency for an increased ADCC basal value was observed in younger patients: median was 76% in the 6 patients ≤ 60 vs 56% in the 23 patients over 60 years-old (p = 0.031). FCGR2A and FCGR3A gene polymorphisms were not linked to basal ADCC. The evolution of individual ADCC ability before treatment and 2 months later revealed a significant drop in ADCC following treatment initiation (intra-patient comparison, n=18, p=0.006), with an absolute median drop of 19%. This decrease was not sustained over time and intra-patient comparison between basal value and 4-month measurement was not significant. 25 patients were assessable for survival (11 deaths). Basal ADCC values were not related to survival. Conclusions: A new generation of mAb is currently being developed with the aim to amplify ADCC. Present data illustrate the feasibility of ADCC measurement in mAb-treated patients and reveal an initial drop in ADCC under treatment that may reflect the variable chemotherapy-induced impact on host immunity.

Organ procurement: experience from a southern Italian region

The authors report their experience of organ procurement during the last 5 years to evaluate a program that began in 1988 to improve organ retrieval in Calabria. In this region only two donations were reported up to 1988, one each in 1980 and 1985. Because of the large population on dialysis and the willingness of a group of surgeons and anesthesiologists, this program was undertaken in 1988 under the supervision of C.C.S.T. (Co-ordination of Centre and South Italy for Transplantation). This program was designed to act on two levels: to create a large group of people directly involved in health care (physicians and nurses) motivated in organ procurement and transplantation, and to diffuse the "culture" of organ donation among lay people. This was achieved by means of scientific meetings inside the hospital and with conventions and TV programs, supported by an Association of Volunteers, where ethical and scientific problems of organ donation and transplantation were discussed in simple language. Various meetings were also held with high school students. During these meetings a questionnaire was distributed among students. Results of this questionnaire show that the main obstacles to organ donation are the "unclear" concept of "brain death" and religious feelings, but after the concept of brain death was explained, a significant number of students showed a different attitude toward organ procurement and transplantation. Results of this program are extremely encouraging (23 organ donations during the last 3 years). We hope to improve our results in the near future, and we do believe that a further and significant increase to our preliminary good results could be achieved by the possibility of performing at least kidney transplantation in our institution.

Dihydropyrimidine dehydrogenase activity in cancer patients

Dihydropyrimidine dehydrogenase (DPD) is the major catabolic enzyme of pyrimidines and fluoropyrimidines. The clinical course of 2 patients with suspected DPD deficiency is described. Both patients had significantly delayed clearance of fluorouracil (5-FU), elevated plasma uracil concentrations, and subsequent lethal toxicity. The prevalence of DPD deficiency in the general population is unknown, but given the large number of cancer patients treated with 5-FU, it may be of great clinical significance. Lymphocytes have been previously shown to be a useful marker of systemic DPD activity. Because DPD activity has not been previously reported in a large population of cancer patients using 5-FU as the substrate, we determined DPD activity in lymphocytes from 66 patients with cancer. DPD activity was determined by a sensitive high performance liquid chromatography method. The mean DPD activity (S.D.) in 66 patients with head and neck cancer was 0.189 (0.071) nomol/min/mg protein with wide interpatient variability (range 0.058-0.357). DPD activity was not correlated to age (r = -0.164, P = 0.188). The mean DPD activity in men [0.192 (0.074)] was not significantly different from that in women [0.172 (0.057); t-test P = 0.418]. Likewise, there was no statistical difference in DPD activity in patients who had not received prior chemotherapy [0.195 (0.066)] to patients receiving one or more cycles of chemotherapy [0.186 (0.074); t-test P = 0.638].

No effect of dose, hepatic function, or nutritional status on 5-FU clearance following continuous (5-day), 5-FU infusion

One hundred and eighty seven patients (155 males, 32 females) with histologically proven and previously untreated head and neck cancer were entered in the study. A total of 222 cycles of therapy were analyzed (cisplatin 100 mg m-2 on day 1 and 5-day continuous intravenous infusion of 5-FU 550-1069 mg m-2 day-1, mean 875.5 mg m-2 day-1). Significant interpatient variability for various 5-FU pharmacokinetic parameters was observed including an almost ten-fold range in 5-FU clearance (5-FU Cl, ml min-1 m-2 = 791-7769, mean 2820.7). Log 5-FU Cl was not modified by 5-FU dose (r = -0.1034, P = 0.124, n = 222). Poor linear correlations between log 5-FU Cl and hepatic function tests were observed (respective r and P values for 222 cycles, log AST:0.0526, 0.4365; Log ALT: -0.1167, 0.0842; Log A1K. Phos.:0.154, 0.0214; Log GGT: 0.0652, 0.3436; Log LDH: -0.0984, 0.1563; Log bilirubin: 0.1278, 0.0601). The log 5-FU Cl was also poorly correlated with the serum concentration of various nutritional proteins (respective r and P values for 222 cycles, Albumin: 0.0110, 0.8714; prealbumin: -0.1067, 0.1129; transferrin: 0.0439, 0.5226). Laboratory data including indices of hepatic function and nutritional status cannot account for the interpatient variability in 5-FU disposition.