Triplet schedule of weekly 5-fluorouracil and alternating irinotecan or oxaliplatin in advanced colorectal cancer: a dose-finding and phase II study

Circulating tumour cell gene expression and chemosensitivity analyses: predictive accuracy for response to multidisciplinary treatment of patients with unresectable refractory recurrent rectal cancer or unresectable refractory colorectal cancer liver metastases

Background

Patients with unresectable recurrent rectal cancer (RRC) or colorectal cancer (CRC) with liver metastases, refractory to at least two lines of traditional systemic therapy, may receive third line intraarterial chemotherapy (IC) and targeted therapy (TT) using drugs selected by chemosensitivity and tumor gene expression analyses of liquid biopsy-derived circulating tumor cells (CTCs).

Methods

In this retrospective study, 36 patients with refractory unresectable RRC or refractory unresectable CRC liver metastases were submitted for IC and TT with agents selected by precision oncotherapy chemosensitivity assays performed on liquid biopsy-derived CTCs, transiently cultured in vitro, and by tumor gene expression in the same CTC population, as a ratio to tumor gene expression in peripheral mononuclear blood cells (PMBCs) from the same individual. The endpoint was to evaluate the predictive accuracy of a specific liquid biopsy precision oncotherapy CTC purification and in vitro culture methodology for a positive RECIST 1.1 response to the therapy selected.

Results

Our analyses resulted in evaluations of 94.12% (95% CI 0.71–0.99) for sensitivity, 5.26% (95% CI 0.01–0.26) for specificity, a predictive value of 47.06% (95% CI 0.29–0.65) for a positive response, a predictive value of 50% (95% CI 0.01–0.98) for a negative response, with an overall calculated predictive accuracy of 47.22% (95% CI 0.30–0.64).

Conclusions

This is the first reported estimation of predictive accuracy derived from combining chemosensitivity and tumor gene expression analyses on liquid biopsy-derived CTCs, transiently cultured in vitro which, despite limitations, represents a baseline and benchmark which we envisage will be improve upon by methodological and technological advances and future clinical trials.

Intensive multidisciplinary treatment strategies and patient resilience to challenge long-term survival in metastatic colorectal cancer: a case report in real life and clinical practice

In fit metastatic colorectal cancer (MCRC), multidisciplinary treatment strategy integrating intensive FIr-B/FOx triplet chemotherapy associated to bevacizumab and secondary metastasectomies significantly improved clinical outcomes up to progression-free survival (PFS) 17 months and overall survival (OS) 44 months. A non-elderly woman affected by rectal cancer, lymph nodes involvement, synchronous unresectable liver metastases, was treated with first-line FIr-B/FOx integrated with two-stage liver resections, short course radiotherapy, anterior rectal resection, with a PFS 9 months and progression-free interval (PFI) 4 months off-treatment. After progression characterized by single liver and lymph node inferior mesenteric axis metastases, FIr-B/FOx was re-introduced, liver and lymph node resections were performed, with a PFS 8 months and PFI 3 months. FIr-B/FOx was further proposed due to bilateral lung, and liver metastases with stable disease, PFS 8 months. Patient experienced a limiting toxicity syndrome multiple sites (LTS-ms) with G3 diarrhea, G2 asthenia, nausea, requiring irinotecan reduction and 5-fluorouracil discontinuation, and subsequent oxaliplatin discontinuation, due to infusional hypersensitivity reaction. Overall, integrated first-line medical and surgical treatment strategies gained PFS 26 months. Further lines II-V of treatment obtained a combined PFS 28 months: modulated aflibercept/irinotecan, PFS 8 months; panitumumab, PFS 8 months, proposed due to KRAS/NRAS/BRAF wild-type and EGFR c.2156 G>C (p.G719A) mutation, achieving biomarkers reduction, lung, liver, lymph nodes partial responses; regorafenib, PFS 8 months; trifluridine-tipiracil, PFS 4 months and induced an LTS-ms, with febrile G4 leucopenia, G3 neutropenia, thrombocytopenia, asthenia, G2 anemia, diarrhea, hypotension. After 2 months of palliative care, patient died, at OS 58 months, gained by intensive medical/surgical treatments coupled with patient's resilience. To date, selection of tailored medical treatments, according to clinical (age, performance and comorbidity status) and molecular (RAS/BRAF and pharmacogenomic analyses) evaluations, careful monitoring of individual toxicity syndromes, potential integration of metastasectomies, and furthermore individual resilience as patient life priority need to challenge MCRC long-term survival.

Relevance of Pharmacogenomics and Multidisciplinary Management in a Young-Elderly Patient With KRAS Mutant Colorectal Cancer Treated With First-Line Aflibercept-Containing Chemotherapy

Introduction: Intensive oncological treatment integrated with resection of metastases raised the clinical outcome of metastatic colorectal cancer (MCRC). In clinical practice, complex evaluation of clinical (age, performance status, comorbidities), and biological (tumoral genotype, pharmacogenomic) parameters addresses tailored, personalized multidisciplinary treatment strategies. Patients with MCRC unsuitable for first-line intensive medical treatments are prevalent and showed worse clinical outcome. After progression to oxaliplatin-based chemotherapy, aflibercept/FOLFIRI significantly improved clinical outcome, even if no survival benefit was reported in adjuvant fast relapsers by aflibercept addition. The case reported a young-elderly (yE) patient with KRAS mutant colorectal cancer rapidly progressing to adjuvant chemotherapy, unfit owing to comorbidities, with multiple pharmacogenomic alterations, who gained long-term survival in clinical practice by multidisciplinary treatment strategy consisting of first-line and re-introduction of aflibercept-containing chemotherapy and two-stage lung metastasectomies.

Case presentation: A 71-years-old yE patient, unfit for intensive oncological treatments owing to Cumulative Illness Rating Scale (CIRS) stage secondary, affected by KRAS c.35 G>T mutant colorectal cancer, rapidly progressing with lung metastases after adjuvant XelOx chemotherapy, reached long-term survival 66 months with no evidence of disease after first-line and re-introduction of tailored, modulated aflibercept (4 mg/kg) d1,15-irinotecan (120 mg/m²) d1,15-5-fluorouracil (750 mg/m²/day) dd1–4, 15–18; and secondary radical bilateral two-stage lung metastasectomies. Safety profile was characterized by limiting toxicity syndrome at multiple sites (LTS-ms), requiring 5-fluorouracil discontinuation and aflibercept reduction (2 mg/kg), because of G2 hand-foot syndrome (HFS) for >2 weeks, and G3 hypertension. Pharmacogenomic analyses revealed multiple alterations of fluoropyrimidine and irinotecan metabolism: severe deficiency of fluorouracil degradation rate (FUDR), single nucleotide polymorphisms of UGT1A1^*28 variable number of tandem repeats (VNTR) 7R/7R homozygote, ABCB1 c.C3435T, c.C1236T, MTHFR c.C667T homozygote, DPYD c.A166G, TSER 28bp VNTR 2R/3R heterozygote.

Conclusions: In clinical practice, a complex management evaluating clinical parameters and RAS/BRAF genotype characterizing an individual patient with MCRC, particularly elderly and/or unfit owing to comorbidities, is required to properly address tailored, multidisciplinary medical and surgical treatment strategies, integrated with careful monitoring of superimposing toxicity syndromes, also related to pharmacogenomic alterations, to gain optimal activity, and long-term efficacy.

Real-life multidisciplinary treatment for unresectable colorectal cancer liver metastases including hepatic artery infusion with chemo-filtration and liquid biopsy precision oncotherapy: observational cohort study

BACKGROUND

Hepatic artery infusion (HAI) and drug selection by liquid biopsy precision oncotherapy are under investigation for the multidisciplinary treatment of unresectable colorectal liver metastases (CRCLM) in progression after systemic therapy. Here, we compare the safety and efficacy of third-line HAI followed by target therapy with drug regimes selected by liquid biopsy precision oncotherapy to third-line systemic therapy with drug regimes selected partly by tissue biopsy precision oncotherapy, in a retrospective real-life study of 106 unresectable CRCLM patients.

METHODS

Drug regimens for HAI/target therapy were selected by assessing the sensitivity of purified circulating tumor cell (CTCs) to 5-fluorouracil, carboplatin, cisplatin, oxaliplatin, irinotecan, doxorubicin, mitomycin, raltitrexed, and melphalan in-vitro and by real-time qRT-PCR gene expression assays, and for the Systemic therapy cohort were selected by age, comorbidity, performance status, and absence of RAS mutations. Therapeutic responses, adverse events, and quality of life were evaluated by RECIST 1.1, CTCAE 4.03, and ECOG criteria, respectively, and chemo-filtration performed following HAI to reduce systemic toxic effects.

RESULTS

HAI/target therapy with drugs selected by liquid biopsy precision oncotherapy (44 patients), resulted in 2.27% CRs, 38.63% PRs, 56.81% SD,s and 2.27% PDs; ECOG 2 to 1 improvement, but no infusion-related technical or vascular complications, or deaths. Systemic therapy (62 patients) resulted in 1.6% CRs, 17.74% PRs, 37.09% SDs, and 45.16% PDs; more grade 1-2 adverse events and 4.84% ECOG 1 to 2 worsening. The median 5 month PFS in the HAI/target therapy cohort was significantly longer than 3 months in the systemic cohort (P < 0.007) and the median 14 month survival in the HAI/target therapy cohort was longer than 8.5 months in the systemic therapy cohort but not statistically significant. Multivariate analysis identified ECOG grade 2 as the most unfavourable survival prognostic factor in both cohorts.

CONCLUSIONS

HAI plus chemo-filtration followed by target therapy, with drug regimens selected by liquid biopsy precision oncotherapy, is a safe and efficacious alternative therapeutic strategy for unresectable CRCLM in progression after two lines of systemic therapy and should be considered for a multicentre prospective phase III study, to fully confirm this potential.

Toxicity Syndromes, Patient-Related Clinical Indicator of Toxicity Burden Induced by Intensive Triplet Chemotherapy-Based Regimens in Gastrointestinal Cancers With Metastatic Disease

Background: Cancer treatments induce symptoms/signs superimposing on individual patient's clinical status, determining heterogenous toxicity syndromes (TS). We reviewed intensive first line triplet chemotherapy-based regimens in metastatic gastro-intestinal cancers (mGI), based on FIr/FOx schedule, fluorouracil and weekly alternating irinotecan/oxaliplatin, to point out limiting TS (LTS) relevance.

Methods: Metastatic colo-rectal (mCRC), pancreatic ductal adenocarcinoma (mPDAC), gastric carcinoma (mGC) patients were enrolled by careful decision-making including age, performance status (PS), and comorbidity status in real life phase II studies: FIr-B/FOx adding bevacizumab (B) overall, FIr-C/FOx-C adding cetuximab (C) in KRAS/NRAS wild-type mCRC; FIr/FOx in mPDAC; FD/FOx adding docetaxel (D) in mGC. Toxicity, individual LTS, LT alone (LTS-single site, LTS-ss) or associated to other limiting/G2 toxicities (LTS-multiple sites, LTS-ms) were evaluated, compared by chi-square test. In FIr-C/FOx-C, 5-fluorouracil/irinotecan pharmacogenomic biomarkers, 5-fluorouracil degradation rate (5-FUDR), SNPs ABCB1, CYP3A4, DYPD, UGT1A1 were evaluated, related with LTS.

Results: FIr-B/FOx, FIr-C/FOx-C in mCRC, FIr/FOx in mPDAC, FD/FOx in mGC, showed activity, efficacy, toxicities similar to reported triplet regimens. LTS: mCRC FIr-B/FOx 44%, LTS-ms 24%, LTS-ss 20%, in young-elderly 46%, LTS-ms significantly increased vs. LTS-ss; FIr-C/FOx-C 65.5%, significantly increased LTS-ms vs. LTS-ss, in young-elderly 83%; mPDAC FIr/FOx 27.5%, mostly LTS-ms, in young-elderly 38.4% all LTS-ms; mGC FD/FOx 30%, all LTS-ms, in young-elderly 25%. Reduced FUDR, SNPs CYP3A4, UGT1A1, >1 positive pharmacogenomic biomarkers were prevalent in patients with gastrointestinal LTS.

Conclusions: LTS is an innovative clinical parameter of toxicity burden, differential treatment-related TS in individual patient. LTS can evaluate pharmacogenomic biomarkers predictive relevance to select mGI patients fit for intensive treatments, at risk of limiting gastrointestinal toxicity.

Trial Registrations: The trials were registered at Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali (OsSC) Agenzia Italiana del Farmaco (AIFA) Numero EudraCT 2007-004946-34, and Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali (OsSC) Agenzia Italiana del Farmaco (AIFA) Numero EudraCT 2009- 016793-32.

Poorly differentiated neuroendocrine rectal carcinoma with uncommon immune-histochemical features and clinical presentation with a subcutaneous metastasis, treated with first line intensive triplet chemotherapy plus bevacizumab FIr-B/FOx regimen: an experience of multidisciplinary management in clinical practice

Background

Neuroendocrine tumors (NETs) are heterogeneous, widely distributed tumors arising from neuroendocrine cells. Gastrointestinal (GI)-NETs are the most common and NETs of the rectum represent 15, 2% of gastrointestinal malignancies. Poorly differentiated neuroendocrine carcinomas of the GI tract are uncommon. We report a rare case of poorly differentiated locally advanced rectal neuroendocrine carcinoma with nodal and a subcutaneous metastasis, with a cytoplasmic staining positive for Synaptophysin and Thyroid Transcription Factor-1.

Case presentation

A 72-year-old male presented to hospital, due to lumbar, abdominal, perineal pain, and severe constipation. A whole-body computed tomography scan showed a mass of the right lateral wall of the rectum, determining significant reduction of lumen caliber. It also showed a subcutaneous metastasis of the posterior abdominal wall. Patient underwent a multidisciplinary evaluation, diagnostic and therapeutic plan was shared and defined. The pathological examination of rectal biopsy and subcutaneous nodule revealed features consistent with small-cell poorly differentiated neuroendocrine carcinoma. First line medical treatment with triplet chemotherapy and bevacizumab, according to FIr-B/FOx intensive regimen, administered for the first time in this young elderly patient affected by metastatic rectal NEC was highly active and tolerable, as previously reported in metastatic colo-rectal carcinoma (MCRC). A consistent rapid improvement in clinical conditions were observed during treatment. After 6 cycles of treatment, CT scan and endoscopic evaluation showed clinical complete response of rectal mass and lymph nodes; patient underwent curative surgery confirming the pathologic complete response at PFS 9 months.

Discussion and conclusions

This case report of a locally advanced rectal NEC with an unusual subcutaneous metastasis deserves further investigation of triplet chemotherapy-based intensive regimens in metastatic GEP NEC.

Weekly alternate intensive regimen FIrB/FOx in metastatic colorectal cancer patients: an update from clinical practice

Background

Several trials evaluated the role of intensive regimens, made of triplet chemotherapies plus bevacizumab, as first-line treatment for patients with metastatic colorectal cancer (mCRC). We previously reported, in a Phase II prospective study, the efficacy and the tolerability of FIrB/FOx regimen, reporting interesting results in terms of received dose intensities (rDIs) and safety.

Methods

We reported a retrospective update of 85 patients treated with FIrB/FOx, an intensive regimen of 5-fluorouracil, bevacizumab, and weekly alternate irinotecan and oxaliplatin, to confirm its feasibility in “real life”. Subgroup analyses were performed, particularly among patients treated with standard and modified FIrB/FOx (based on age, performance status, and/or comorbidities).

Results

Overall, 3-month objective response rate (ORR) and 6-month ORR were 75.9% and 55.3%, respectively. Median progression-free survival (PFS) and median overall survival (OS) were 14.4 and 34.9 months, respectively. Among the patients treated with standard and modified regimens, 3-month ORR, PFS, and OS were 75.8% and 76% (P=1.0000), 14.4 and 14.4 months (P=0.8589), and 37.8 and 26.6 months (P=0.7746), respectively. Among the K/NRAS wild-type and K/NRAS mutant patients, 3-month ORR, PFS, and OS were 95.2% and 74.5% (P=0.0526), 15.3 and 14.4 months (P=0.8753), and 37.8 and 51.4 months (P=0.8527), respectively. The rDIs were ≥80% of full doses both in the standard and in the modified regimens subgroups. Cumulative G3/4 toxicities were neutropenia (14.1%), diarrhea (17.6%), asthenia (9.4%), vomiting (5.6%), and hypertension (16.5%).

Conclusion

This update shows that intensive regimens such as FIrB/FOx are also feasible options for first-line treatment of mCRC patients in the “real-life” setting.

Real life triplet FIr/FOx chemotherapy in first-line metastatic pancreatic ductal adenocarcinoma patients: recommended schedule for expected activity and safety and phase II study

BACKGROUND

Gemcitabine/nab-paclitaxel and FOLFIRINOX demonstrated significantly increased survival compared with gemcitabine in metastatic pancreatic ductal adenocarcinoma (PDAC): objective response rate (ORR) 23 and 31.6%, progression-free survival (PFS) 5.5 and 6.4 months, overall survival (OS) 8.7 and 11.1 months. Present phase II study evaluated recommended first-line triplet FIr/FOx schedule.

METHODS

Simon two-step design: p010%, p130%, power 80%, α5%, β20%. Projected ORR: I step, 1/10; II 5/29. Schedule: 12h-timed-flat-infusion/5-fluorouracil 750-800-900 mg/m2 d1-2,8-9,15-16,22-23; irinotecan 120-140-160 mg/m2 d1,15; oxaliplatin 70-80 mg/m2 d8,22; every 4 weeks, according to clinical parameters (age, comorbidities, performance status (PS), liver function). Activity and efficacy were evaluated, and compared using log-rank; limiting toxicity syndromes (LTS), using chi-square.

RESULTS

Twenty-nine consecutive patients were enrolled, according to primary/intermediate/secondary Cumulative Illness Rating Scale (CIRS). Median age 62; elderly 13 (44.7%); PS2 3 (10.4%), secondary CIRS 5 (17.2%). Primary endpoint was met: ORR 53% (7/13 patients) as-treated, 50% intent-to-treat. Cumulative G3-4 toxicities: diarrhea 17%, asthenia 14%, hypertransaminasemy 7%, mucositis 7%, vomiting 3%, anemia 3%, thrombocytopenia 3%. LTS were 27.5% overall, 38.4% in elderly. At 3 months median follow-up, PFS 4 months, OS 11 months. PS2 patients showed significantly worse OS (P 0.022).

CONCLUSION

Intensive first-line triplet FIr/FOx is tolerable at modulated doses, and confirms high activity/efficacy in metastatic PDAC. Patients' careful selection, and exclusion of PS2, can maintain safety profile and efficient dose intensity.

Dose-finding study of intensive weekly alternating schedule of docetaxel, 5-fluorouracil, and oxaliplatin, FD/FOx regimen, in metastatic gastric cancer

INTRODUCTION

Proper administration timing, dose-intensity, efficacy/toxicity ratio of triplet docetaxel (DTX), 5-fluorouracil (5-FU), and oxaliplatin (OXP) should be improved to safely perform three-drugs intensive first line in advanced gastric cancer (GC). This dose-finding study investigated recommended 5-FU and OXP doses, safety of triplet regimen and preliminary activity.

METHODS

Schedule: 12h-timed-flat-infusion 5-FU 700-1000 mg/m2/d 1-2, 8-9, 15-16, 22-23, with 100 mg/m2/d increase for dose level; DTX 50 mg/m2 d 1, 15 fixed dose, OXP at three increasing dose-levels 60-70-80 mg/m2 d 8, 22, every 4 weeks. Intra- and inter-patients dose-escalation was planned.

RESULTS

Ten fit <75 years patients were enrolled: median age 59; young-elderly 4 (40%). From first to fifth dose level, 5 patients (1 per cohort) were enrolled according to intra-patient dose escalation, no dose-limiting toxicity (DLT) were reported. At sixth level, 1 DLT, G2 diarrhea, was reported, thus other 2 patients were enrolled, DLT 1/3 patients (33%). Maximum tolerated dose (MTD) was not reached. 5-FU and OXP recommended doses (RD) were 1000 mg/m2/d and 80 mg/m2, respectively. To confirm RD, other 3 patients were enrolled, without DLT. Cumulative G3-4 toxicities were: neutropenia 50%, leucopenia 20%, hypoalbuminemia 10%, mucositis 10%, asthenia 20%. Limiting toxicity syndromes were 30%, 25% in young-elderly, all multiple site. Objective response rate intent-to-treat 60%, disease control rate 90%. After 15 months follow-up, progression-free and overall survival, 6 and 17 months, respectively.

CONCLUSIONS

First line intensive FD/FOx regimen adding DXT/5-FU/OXP can be safely administered at recommended doses in advanced GC, with promising high activity and efficacy.

Topical Menthol for Treatment of Chemotherapy-induced Peripheral Neuropathy

Chemotherapy-induced peripheral neuropathy is a frequent treatment-limiting factor that significantly impairs patients’ everyday life, also because of a lack of valid palliative options. Here, we report a case of a male patient with a history of metastatic colon cancer and previous chemotherapies. He came to our attention with a peripheral neuropathy that impaired his quality of life and could limit the further line of chemotherapy. We treated the neuropathy with menthol aqueous cream with benefit.

Efficacy of triplet combination chemotherapy with oxaliplatin, irinotecan and capecitabine (OCX) in metastatic colorectal cancer in relation to RAS/RAF mutation status: results of a retrospective analysis

BACKGROUND

The triplet combination of fluorouracil, oxaliplatin and irinotecan for metastatic colorectal cancer improves efficacy at the cost of increased toxicity. Preliminary reports indicate that triplet combination regimens might improve outcome in the RAS/RAF-mutated subgroup.

PATIENTS AND METHODS

This retrospective analysis included 25 patients with metastatic colorectal cancer, who received treatment with OCX (oxaliplatin, irinotecan, capecitabine). The regimen consisted of oxaliplatin 70 mg/m2 on days 1 and 15, irinotecan 100 mg/m2 on days 8 and 22, and capecitabine 1,400 mg/m2 on days 1-29 every 5 weeks. KRAS, NRAS, and BRAF mutations were determined by Sanger sequencing.

RESULTS

23 patients received at least 1 cycle and were evaluable for efficacy. In 10 patients, a KRAS or BRAF mutation was detected. Partial remission rate was 61%, median progression-free survival 9.8 months, and median overall survival 32.9 months for all evaluable patients. No difference in efficacy was detected between the RAS/RAF wild-type and the mutant group. OCX was well tolerated with no grade 3/4 haematological events. Diarrhoea was the major non-haematological toxicity (24% grade 3).

CONCLUSION

In this retrospective analysis, triplet chemotherapy with OCX was well tolerated and achieved encouraging efficacy in metastatic colorectal cancer irrespective of RAS/RAF mutation status.

Prognostic relevance of KRAS genotype in metastatic colorectal cancer patients unfit for FIr-B/FOx intensive regimen

First-line triplet chemotherapy plus bevacizumab (FIr-B/FOx) can improve efficacy of metastatic colorectal cancer (MCRC), KRAS wild-type and mutant. Prognostic relevance of KRAS genotype was evaluated in patients unfit for FIr-B/FOx, treated with conventional medical treatments. Consecutive MCRC patients not eligible for FIr-B/FOx regimen due to age (≥75 years) and/or comorbidities were treated with tailored conventional first-line treatments. KRAS codon 12/13 mutations were screened by direct sequencing. Activity and efficacy were evaluated and compared according to medical treatments, age (non-elderly and elderly≥65 years), comorbidity stage (Cumulative Illness Rating Scale), metastatic extension (liver-limited and other/multiple metastatic), and KRAS genotype, using log-rank. Selected first line treatments were medical in 37 patients (92.5%), and surgical in 3 patients (7.5%). Medical treatment regimens: triplet, 18 (45%); doublet, 15 (37.5%); mono-therapy, 4 (10%). At median follow-up of 8 months, objective response rate (ORR) was 37%, median progression-free survival (PFS) 7 months, liver metastasectomies 8% (liver-limited disease 37.5%), median overall survival (OS) 13 months. Triplet regimens failed to significantly affect clinical outcome, compared to doublet. According to KRAS genotype, ORR, PFS and OS were, respectively: wild-type 50%, 8 months, 13 months; mutant 25%, 6 months, 9 months. KRAS genotype wild-type compared to mutant significantly affected PFS, while not OS. KRAS c.35 G>A mutation (G12D) significantly affected worse PFS and OS compared to wild-type and/or other mutations. KRAS genotype, specifically the c.35 G>A KRAS mutation, may indicate poor prognosis in MCRC patients unfit for intensive medical treatments.

Differential prognosis of metastatic colorectal cancer patients post-progression to first-line triplet chemotherapy plus bevacizumab, FIr-B/FOx, according to second-line treatment and KRAS genotype

Clinical outcome post-progression to first-line triplet chemotherapy (CT) plus bevacizumab (FIr-B/FOx) was evaluated in metastatic colorectal cancer (MCRC) patients (pts). Second-line treatment was selected according to fitness, KRAS genotype, previous efficacy and safety. Efficacy was evaluated and compared according to treatment or KRAS genotype, using log-rank analysis. Among 54 pts, median overall survival (OS) post-progression was 12 months, significantly better in 40 (74.1%) treated compared to 14 (25.9%) who died without further treatment. Second-line surgical treatment, 4 pts (7.4%), medical treatment, 36 pts (66.7%): triplet CT plus targeted agent, 10 (18.5%); triplet regimens, 19 (35.2%); doublet/monotherapy, 7 (13%). At follow-up of 14 months, objective response rate (ORR) was 38%, metastasectomies 12.5%, progression-free survival (PFS) 10 months, OS 14 months. According to treatment, ORR, metastasectomies, PFS and OS were significantly favourable in triplet CT plus targeted agent compared to triplet, respectively: 80%, 40%, 13 months, not reached; 28%, 6%, 8 months, 11 months. PFS and OS were significantly worse in c.35 G>A mutant compared to wild-type and/or other mutant patients. Prognosis after progression to first‑line FIr-B/FOx may be significantly favourable in MCRC pts re-challenged with intensive regimens, and unfavourable in c.35 G>A KRAS mutant patients.

Effectiveness and safety of intensive triplet chemotherapy plus bevacizumab, FIr-B/FOx, in young-elderly metastatic colorectal cancer patients

Four-drug regimens, such as FIr-B/FOx schedule, can improve efficacy of first-line treatment of metastatic colorectal cancer (MCRC) patients. The present study specifically evaluates feasibility of FIr-B/FOx first-line intensive regimen in fit young-elderly MCRC patients, representing approximately 40% of overall MCRC patients. Activity, efficacy, and safety were equivalent to overall MCRC patients, not significantly different according to KRAS genotype. Clinical outcome was significantly prolonged in liver-limited compared to other/multiple metastatic disease. Safety evaluation of the individual young-elderly patient showed that limiting toxicity syndromes (LTS) in multiple sites were significantly increased, compared to LTS in single site, with respect to non-elderly patients.

Prognostic value of KRAS genotype in metastatic colorectal cancer (MCRC) patients treated with intensive triplet chemotherapy plus bevacizumab (FIr-B/FOx) according to extension of metastatic disease

BACKGROUND

Bevacizumab (BEV) plus triplet chemotherapy can increase efficacy of first-line treatment of metastatic colorectal cancer (MCRC), particularly integrated with secondary liver surgery in liver-limited (L-L) patients. The prognostic value of the KRAS genotype in L-L and other or multiple metastatic (O/MM) MCRC patients treated with the FIr-B/FOx regimen was retrospectively evaluated.

METHODS

Tumoral and metastatic samples were screened for KRAS codon 12 and 13 and BRAF mutations by SNaPshot and/or direct sequencing. Fit MCRC patients <75 years were consecutively treated with FIr-B/FOx regimen: weekly 12-h timed flat-infusion/5-fluorouracil (TFI 5-FU) 900 mg/m2, days 1, 2, 8, 9, 15, 16, 22 and 23; irinotecan (CPT-11) 160 mg/m2 plus BEV 5 mg/kg, days 1, 15; oxaliplatin (OXP) 80 mg/m2, days 8, 22; every 4 weeks. MCRC patients were classified as L-L and O/MM. Activity and efficacy were evaluated and compared using log-rank test.

RESULTS

In all, 59 patients were evaluated: 31 KRAS wild-type (53%), 28 KRAS mutant (47%). At 21.5 months median follow-up, objective response rate (ORR), progression-free survival (PFS) and overall survival (OS) were, respectively: KRAS wild-type 90%, 14 months, 38 months; KRAS mutant 67%, 11 months, 20 months. PFS and OS were not significantly different. PFS and OS were significantly different in L-L compared to O/MM evaluable patients. In KRAS wild-type patients, clinical outcome of 12 L-L compared to 18 O/MM was significantly different: PFS 21 versus 12 months and OS 47 versus 28 months, respectively. In KRAS mutant patients, the clinical outcome of 13 L-L compared to 14 O/MM was not significantly different: PFS 11 months equivalently and OS 39 versus 19 months, respectively.

CONCLUSIONS

The KRAS genotype wild-type and mutant does not significantly affect different clinical outcomes for MCRC patients treated with the first-line FIr-B/FOx intensive regimen. KRAS wild-type patients with L-L disease may achieve a significantly prolonged clinical outcome due to integration with secondary liver surgery, with respect to KRAS mutant patients.

"Poker" association of weekly alternating 5-fluorouracil, irinotecan, bevacizumab and oxaliplatin (FIr-B/FOx) in first line treatment of metastatic colorectal cancer: a phase II study

BACKGROUND

This phase II study investigated efficacy and safety of weekly alternating Bevacizumab (BEV)/Irinotecan (CPT-11) or Oxaliplatin (OHP) associated to weekly 5-Fluorouracil (5-FU) in first line treatment of metastatic colorectal carcinoma (MCRC).

METHODS

Simon two-step design: delta 20% (p0 50%, p1 70%), power 80%, α 5%, β 20%. Projected objective responses (ORR): I step, 8/15 patients (pts); II step 26/43 pts. Schedule: weekly 12 h-timed-flat-infusion/5-FU 900 mg/m2, days 1-2, 8-9, 15-16, 22-23; CPT-11 160 mg/m2 plus BEV 5 mg/kg, days 1,15; OHP at three dose-levels, 60-70-80 mg/m2, days 8, 22; every 4 weeks.

RESULTS

Fifty consecutive, unselected pts < 75 years were enrolled: median age 63; young-elderly (yE) 24 (48%); liver metastases (LM) 33 pts, 66% Achieved OHP recommended dose, 80 mg/m2. ORR 82% intent-to-treat and 84% as-treated analysis. Median progression-free survival 12 months. Equivalent efficacy was obtained in yE pts. Liver metastasectomies were performed in 26% of all pts and in 39% of pts with LM. After a median follow-up of 21 months, median overall survival was 28 months. Cumulative G3-4 toxicities per patient: diarrhea 28%, mucositis 6%, neutropenia 10%, hypertension 2%. They were equivalent in yE pts. Limiting toxicity syndromes (LTS), consisting of the dose-limiting toxicity, associated or not to G2 or limiting toxicities: 44% overall, 46% in yE. Multiple versus single site LTS, respectively: overall, 24% versus 20%; yE pts, 37.5% versus 8%.

CONCLUSION

Poker combination shows high activity and efficacy in first line treatment of MCRC. It increases liver metastasectomies rate and can be safely administered.

TRIAL REGISTRATION

Osservatorio Nazionale sulla Sperimentazione Clinica dei Medicinali (OsSC) Agenzia Italiana del Farmaco (AIFA) Numero EudraCT 2007-004946-34.