A signature of circulating microRNAs predicts the response to treatment with FOLFIRI plus aflibercept in metastatic colorectal cancer patients.

The benefit of adding the antiangiogenic drug aflibercept to FOLFIRI regime in metastatic colorectal cancer (CRC) patients resistant to or progressive on an oxaliplatin-based therapy has been previously demonstrated. However, the absence of validated biomarkers to predict greater outcomes is a major challenge encountered when using antiangiogenic therapies. In this study we investigated profiles of circulating microRNAs (miRNAs) to build predictive models of response to treatment and survival. Plasma was obtained from 98 metastatic CRC patients enrolled in a clinical phase II trial before receiving FOLFIRI plus aflibercept treatment, and the circulating levels of 754 individual miRNAs were quantified using real-time PCR. A distinct signature of circulating miRNAs differentiated responder from non-responder patients. Remarkably, most of these miRNAs were found to target genes that are involved in angiogenic processes. Accordingly, some of these miRNAs had predictive value and entered in predictive models of response to therapy, progression of disease, and survival of patients treated with FOLFIRI plus aflibercept. Among these miRNAs, circulating levels of hsa-miR-33b-5p efficiently discriminated between responder and non-responder patients and predicted the risk of disease progression. Moreover, the combination of circulating VEGF-A and miR-33b-5p levels improved clinical stratification of metastatic CRC patients who were to receive FOLFIRI plus aflibercept treatment. In conclusion, our study supports circulating miRNAs as valuable biomarkers for predicting better outcomes in metastatic CRC patients treated with FOLFIRI plus aflibercept.

Clinical Management of Cutaneous Adverse Events in Patients on Chemotherapy: A National Consensus Statement by the Spanish Academy of Dermatology and Venereology and the Spanish Society of Medical Oncology. / Manejo clínico de los eventos adversos cutáneos en pacientes tratados con quimioterapia: consenso nacional de la Academia Española de Dermatología y Venereología y de la Sociedad Española de Oncología Médica.

Although the arrival of new chemotherapy drugs and combinations has brought progress in terms of cancer patient survival, they entail many adverse effects that can compromise treatment, and hence prognosis, of the disease. Cytostatic agents can cause dermatological toxicity, among other side effects. The most familiar adverse effect of chemotherapy is alopecia. Although not serious, this changes the outward appearance of cancer patients. Other adverse effects include hypersensitivity and photosensitivity reactions, hand-foot syndrome, epidermal necrolysis, recall reactions, scleroderma-like reactions, Raynaud's phenomenon, eccrine squamous syringometaplasia, neutrophilic eccrine hidradenitis, nail abnormalities, pigmentation changes and extravasation injuries. Onset of these adverse effects often causes dose reduction and/or delayed treatment, which can affect patient survival and quality of life. It is therefore important to prevent their occurrence and treat them promptly, which requires cooperation between medical oncologists and dermatologists. This article reviews chemotherapy-associated dermatological toxicity, along with its diagnosis and therapeutic management.

Clinical management of cutaneous adverse events in patients on targeted anticancer therapies and immunotherapies: a national consensus statement by the Spanish Academy of Dermatology and Venereology and the Spanish Society of Medical Oncology.

Progress in the understanding of many tumors has enabled the development of new therapies, such as those targeted at specific molecules involved in cell growth (targeted therapies) or intended to modulate the immune system (immunotherapy). However, along with the clinical benefit provided by these new treatments, new adverse effects have also appeared. Dermatological toxicities such as papulopustular eruptions, xerosis, and pruritus are common with EGFR inhibitors. Other adverse effects have also been described with PDGFR, BCR-ABL, and MAPK tyrosine kinase inhibitors, antiangiogenic drugs, and inhibitors at immune checkpoints such as CTLA-4 and PD-1/PD-L1. Onset of these adverse effects often causes dose reductions and/or delays in administering the prescribed therapy, which can affect patient survival and quality of life. It is, therefore, important to prevent the occurrence of these adverse effects, or to treat unavoidable ones as soon as possible. This requires cooperation between medical oncologists and dermatologists. This article reviews the various dermatological toxicities associated with targeted therapies and immunotherapies, along with their diagnosis and therapeutic management.

First-line mFOLFOX plus cetuximab followed by mFOLFOX plus cetuximab or single-agent cetuximab as maintenance therapy in patients with metastatic colorectal cancer: Phase II randomised MACRO2 TTD study.

BACKGROUND: This multicentre, randomised, and phase II study evaluated mFOLFOX+cetuximab followed by maintenance mFOLFOX+cetuximab or single-agent cetuximab in metastatic colorectal cancer (mCRC) patients (NCT01161316). PATIENTS AND METHODS: Previously, untreated mCRC patients (wild-type KRAS) were randomised to receive cetuximab+mFOLFOX-6 (8 cycles for 2 weeks) followed by maintenance therapy: single-agent cetuximab (Arm-A) or mFOLFOX-6 + cetuximab (Arm-B) until progression. Primary endpoint was progression-free survival (PFS) at 9 months. RESULTS: One hundred ninety-three patients (median [range] age 60 [33-74] years) were randomised (2:1): 129 Arm-A versus 64 Arm-B. PFS at 9 months (95% confidence interval) showed non-inferiority between arms (Arm-A/Arm-B: 60 [52, 69]%/72 [61, 83]%, p [non-inferiority]<0.1). There were no statistically significant differences in the PFS (Arm-A/Arm-B: 9 [95% CI 7, 10] months/10 [7,13] months, hazard ratio [HR] = 1.19 [0.80, 1.79]) or overall survival (23 [19, 28] months/27 [18, 36] months, HR = 1.24 [0.85, 1.79]) between arms. The objective response rate was also similar (48 [39, 57]%/39 [27, 52]%). The safety profile was similar between arms, and all patients experienced at least one adverse event (AE) (Arm-A/Arm-B grade ≥III AEs: 70%/68%). The most common grade ≥III AEs were as follows: neutropenia (Arm-A/Arm-B: 28%/26%), rash acneiform (15%/24%) and sensory neuropathy (2%/15%) in any group. Arm-A was associated with less grade ≥III rash and sensory neuropathy and a lower rate of serious AEs (20%/27%). CONCLUSION(S): This phase II exploratory trial with a non-inferiority design suggests that maintenance therapy with single-agent cetuximab following mFOLFOX+cetuximab induction could be a valuable option compared with mFOLFOX+cetuximab treatment continuation. We await phase III trials to confirm single-agent cetuximab as maintenance therapy in mCRC patients.

SEOM clinical guideline for treatment of cancer pain (2017).

Pain is a highly prevalent symptom in patients with cancer. Despite therapeutic advances and well-accepted treatment guidelines, a percentage of patients with pain are under-treated. Currently, it has been recognized that several barriers in pain management still exist and, in addition, there are new challenges surrounding complex subtypes of pain, such as breakthrough and neuropathic pain, requiring further reviews and recommendations. This is an update of the guide our society previously published and represents the continued commitment of SEOM to move forward and improve supportive care of cancer patients.

Genotype-based selection of treatment of patients with advanced colorectal cancer (SETICC): a pharmacogenetic-based randomized phase II trial.

Background: There has been little progress toward personalized therapy for patients with metastatic colorectal cancer (mCRC). TYMS-3' untranslated region (UTR) 6 bp ins/del and ERCC1-118C/T polymorphisms were previously reported to facilitate selecting patients for fluoropyrimidine-based treatment in combination with oxaliplatin as first-line therapy. We assessed the utility of these markers in selecting therapy for patients with mCRC. Patients and methods: This randomized, open-label phase II trial compared bevacizumab plus XELOX (control) versus treatment tailored according to TYMS-3'UTR 6 bp ins/del and ERCC1-118C/T polymorphisms. Patients randomized to the experimental treatment received bevacizumab plus FUOX, FUIRI, XELIRI, or XELOX depending on their combination of favorable polymorphisms for FUOX treatment (TYMS-3'UTR ins/del or del/del; ERCC1-118T/T). Progression-free survival (PFS) was the primary end point. Results: Overall, 195 patients were randomized (control n = 65; experimental n = 130). The primary objective was not met: median PFS was 9.4 months in the control group and 10.1 months in the experimental group (P = 0.745). Median overall survival was similar in both groups (16.5 versus 19.1 months, respectively; P = 0.797). Patients in the experimental group had a significantly higher overall response rate (ORR; 65% versus 47% in the control group; P = 0.042) and R0 resection rate (86% versus 44%, respectively; P = 0.018). Neuropathy, hand-foot syndrome, thrombocytopenia, and dysesthesia were significantly less common in the experimental group. Conclusions: This study did not show survival benefits after treatment personalization based on polymorphisms in mCRC. However, the improved ORR and R0 resection rate and fewer disabling toxicities suggest that tailoring therapy by TYMS-3'UTR and ERCC1-118 polymorphisms warrants further investigation in patients with mCRC. ClinicalTrials.gov: NCT01071655.

Peculiarities of the obese patient with cancer: a national consensus statement by the Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology.

The relationship between obesity and cancer is clear and is present at all times during course of the disease. The importance of obesity in increasing the risk of developing cancer is well known, and some of the most prevalent tumours (breast, colorectal, and prostate) are directly related to this risk increase. However, there is less information available on the role that obesity plays when the patient has already been diagnosed with cancer. Certain data demonstrate that in some types of cancer, obese patients tolerate the treatments more poorly. Obesity is also known to have an impact on the prognosis, favouring lower survival rates or the appearance of secondary tumours. In this consensus statement, we will analyse the scientific evidence on the role that obesity plays in patients already diagnosed with cancer, and the available data on how obesity control can improve the quality of daily life for the cancer patient.

Efficacy of trifluridine and tipiracil (TAS-102) versus placebo, with supportive care, in a randomized, controlled trial of patients with metastatic colorectal cancer from Spain: results of a subgroup analysis of the phase 3 RECOURSE trial.

PURPOSE: TAS-102 is a combination of the thymidine-based nucleoside analog trifluridine and the thymidine phosphorylase inhibitor tipiracil. Efficacy and safety of TAS-102 in patients with metastatic colorectal cancer (mCRC) refractory or intolerant to standard therapies were evaluated in the phase 3 RECOURSE trial. Results of RECOURSE demonstrated significant improvement in overall survival (OS) and progression-free survival (PFS) with TAS-102 versus placebo [hazard ratio (HR) = 0.68 and 0.48 for OS and PFS, respectively; both P < 0.001]. The current analysis evaluates efficacy and safety of TAS-102 in the RECOURSE Spanish subgroup. METHODS: Primary and key secondary endpoints were evaluated in a post hoc analysis of the RECOURSE Spanish subgroup, using univariate and multivariate analyses. Safety and tolerability were reported with descriptive statistics. RESULTS: The RECOURSE Spanish subgroup included 112 patients (mean age 61 years, 62 % male). Median OS was 6.8 months in the TAS-102 group (n = 80) versus 4.6 months in the placebo group (n = 32) [HR = 0.47; 95 % confidence interval (CI): 0.28-0.78; P = 0.0032). Median PFS was 2.0 months in the TAS-102 group and 1.7 months in the placebo group (HR = 0.47; 95 % CI: 0.30-0.74; P = 0.001). Eighty (100 %) TAS-102 versus 31 (96.9 %) placebo patients had adverse events (AEs). The most common drug-related ≥Grade 3 AE was neutropenia (40 % TAS-102 versus 0 % placebo). There was 1 (1.3 %) case of febrile neutropenia in the TAS-102 group versus none in the placebo group. CONCLUSIONS: In the RECOURSE Spanish subgroup, TAS-102 was associated with significantly improved OS and PFS versus placebo, consistent with the overall RECOURSE population. No new safety signals were identified. CLINICALTRIALS. GOV STUDY NUMBER: NCT01607957.

SEOM Clinical Guideline for bone metastases from solid tumours (2016).

Bone metastases are common in many advanced solid tumours, being breast, prostate, thyroid, lung, and renal cancer the most prevalent. Bone metastases can produce skeletal-related events (SREs), defined as pathological fracture, spinal cord compression, need of bone irradiation or need of bone surgery, and hypercalcaemia. Patients with bone metastases experience pain, functional impairment and have a negative impact on their quality of life. Several imaging techniques are available for diagnosis of this disease. Bone-targeted therapies include zoledronic acid, a potent biphosfonate, and denosumab, an anti-RANKL monoclonal antibody. Both reduce the risk and/or delay the development of SREs in several types of tumours. Radium 233, an alpha-particle emitter, increases overall survival in patients with bone metastases from resistant castration prostate cancer. Multidisciplinary approach is essential and bone surgery and radiotherapy should be integrated in the treatment of bone metastases when necessary. This SEOM Guideline reviews bone metastases pathogenesis, clinical presentations, lab tests, imaging techniques for diagnosis and response assessment, bone-targeted agents, and local therapies, as radiation and surgery, and establishes recommendations for the management of patients with metastases to bone.

Is regorafenib providing clinically meaningful benefits to pretreated patients with metastatic colorectal cancer?

Treatment with regorafenib has demonstrated statistically significant improvements in terms of overall survival, progression-free survival and disease control when compared with placebo in pretreated patients with metastatic colorectal cancer in two placebo-controlled, randomized, phase III trials (CORRECT and CONCUR). Similar results were observed in two open-label, single-arm studies (REBECCA and CONSIGN) performed in the real-world setting. But several authors have suggested that the benefit provided by regorafenib may not be clinically meaningful for these patients. Moreover, it has been suggested that not all subgroups of patients might benefit from regorafenib. The intention of this review is to provide an overview of the existing evidence for regorafenib in terms of efficacy, tolerability and quality of life in different subpopulations according to clinical and biological characteristics. Additionally, the magnitude of the clinical benefit provided by regorafenib to these patients has been explored and whether there are poorer outcomes in certain subpopulations.

Seom guidelines for the treatment of gastric cancer 2015.

Gastric cancer is the fourth cause of death by cancer in Spain and a significant medical problem. Molecular biology results evidence that gastroesophageal junction tumors and gastric cancer should be considered as two independent entities with a different prognosis and treatment approach. Endoscopic resection in very early tumors is feasible. Neoadjuvant and adjuvant therapy in locally advanced resectable tumor increase overall survival and should be considered standard treatments. In stage IV tumors, platinum-fluoropyrimidine-based schedule, with trastuzumab in HER2-overexpressed tumors, is the first-line treatment. Different therapies in second line have demonstrated in randomized studies their clear benefit in survival improvement.

Obesity as a risk factor in cancer: A national consensus of the Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology.

In the last few years, many prospective studies have demonstrated a clear association between obesity and cancers of the colon and rectum, breast in post-menopausal women, endometrium, kidney, oesophagus and pancreas. Obesity is also associated with a high risk of recurrence and cancer-related death. The pathophysiology of obesity involves various changes that may be implicated in the relationship between obesity and cancer, such as excess inflammatory cytokines and chronic inflammation, hyperinsulinaemia, insulin resistance, and raised leptin and oestrogens. The Spanish Society for the Study of Obesity and the Spanish Society of Medical Oncology have signed a cooperation agreement to work together towards reducing the impact of obesity in cancer. Preventing obesity prevents cancer.

First-line single-agent panitumumab in frail elderly patients with wild-type KRAS metastatic colorectal cancer and poor prognostic factors: A phase II study of the Spanish Cooperative Group for the Treatment of Digestive Tumours.

BACKGROUND: Frail elderly patients with metastatic colorectal cancer (mCRC) are not candidates for chemotherapy. Monotherapy with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies may be an option for these patients with few systemic toxic effects. PATIENTS AND METHODS: Single-arm, multicentre, phase II trial including patients ⩾ 70y ears with wild-type (WT) KRAS (exon 2) mCRC, Eastern Cooperative Oncology Group (ECOG) status ⩽ 3, KPC (Köhne Prognostic Classification)--defined intermediate or high risk status, frailty and/or ineligibility for chemotherapy. Patients received panitumumab until progression or unacceptable toxicity. The primary end-point was progression free survival (PFS) rate at 6 months. RESULTS: The study included 33 patients (intention-to-treat (ITT) population). Median age: 81 years; sex: 66.7% male; high-risk KPC status: 45.4%. Median treatment duration was 14 weeks and 6-month PFS rate was 36.4% (95% confidence interval (CI): 20.0-52.8). The objective response rate: 9.1% (95% CI: 0-18.9) (all partial responses), and there were 18 stable diseases (54.5%). Median PFS was 4.3 months (95% CI: 2.8-6.4) and median overall survival (OS) was 7.1 months (95% CI: 5.0-12.3). There were no deaths or grade 4-5 adverse events (AEs) related to panitumumab and the most common grade 3-related AE was rash acneiform (15.2%). A significant association between clinical response and RAS status was observed (P=0.037). In the WT RAS subgroup (WT exons 2, 3, and 4 of KRAS and NRAS, N = 15), 6-month PFS rate was 53.3% (95% CI: 30.1-75.2) and median PFS and OS were 7.9 and 12.3 months, respectively. CONCLUSIONS: Single-agent panitumumab is active and well tolerated and may be a therapeutic option for high-risk frail elderly patients with WT RAS tumours considered not candidates for chemotherapy (clinicaltrials.gov identifier NCT01126112).

Role of circulating tumor cells as prognostic marker in resected stage III colorectal cancer.

BACKGROUND: The prognostic role of circulating tumor cells (CTC) in early colorectal cancer (CRC) has not been determined yet. We evaluated the potential prognostic value of CTC in stage III CRC patients. PATIENTS AND METHODS: Prospective multicenter study of 519 patients with stage III CRC recruited between January 2009 and June 2010. CTC were enumerated with the CellSearch System after primary tumor resection and before the start of adjuvant therapy. A total of 472 patients were included in the analysis. RESULTS: CTC ≥1, ≥2, ≥3 and ≥5 were detected in 166 (35%), 93 (20%), 57 (12%) and 34 (7%) patients, respectively. Median follow-up was 40 months. In the overall population, CTC ≥1 (disease-free survival (DFS): HR 0.97, P = 0.85; overall survival (OS): HR 1.03, P = 0.89), ≥2 (DFS: HR 1.07, P = 0.76; OS: HR 1.02, P = 0.95), ≥3 (DFS: HR 0.96, P = 0.87; OS: HR 0.74, P = 0.41) and ≥5 (DFS: HR 0.72, P = 0.39; OS: HR 0.48, P = 0.21) were not associated with worse DFS and OS. No clinicopathological characteristics were significantly associated with the presence of CTC. In patients with disease relapse, the proportion with CTC ≥1 was not significantly different between those with single versus multiple metastatic locations (37.9% versus 31.4%, P = 0.761). In the multivariate analysis, CTC ≥1 was not an independent prognostic factor for DFS (HR 0.97, P = 0.87) and OS (HR 0.96, P = 0.89). CONCLUSION: CTC detection was not associated with worse DFS and OS in patients with stage III CRC. Given the scarcity of CTC in these patients, it is likely that CTC determined by CellSearch system does not have a prognostic role in this setting. However, a longer follow-up is needed.

Clinical management of regorafenib in the treatment of patients with advanced colorectal cancer.

Colorectal cancer is one of the most common tumors worldwide and at least 50 % of patients with this disease develop metastases. In this setting, additional treatment options are needed for patients presenting disease progression after exhausting all standard therapies. Regorafenib is an orally administered multikinase inhibitor which has been shown to provide survival benefits to patients with metastatic colorectal cancer (mCRC). Although most adverse events (AEs) associated with regorafenib may resolve within the first 8 weeks of treatment, some of them may require dose reduction or treatment interruption. Overall, while remaining aware of the safety profile of regorafenib and how to manage the most common toxicities related to its use, this drug should be considered a new standard of care for patients with pretreated mCRC. This review addresses practical aspects of its use, such as dosing, patient monitoring, and management of the most common regorafenib-related AEs.

[Validation of genetic polymorphisms associated to the toxicity of chemotherapy in colorectal cancer patients]. / Validación de polimorfismos genéticos asociados a toxicidad al tratamiento quimioterápico en pacientes de cáncer colorrectal.

OBJECTIVE: To validate the associations previously found in three cohorts of patients from the General University Hospital Gregorio Marañón, between the polymorphisms rs1128503, rs2032582 and rs1045642 of the ABCB1 gene and the hand-foot syndrome and diarrhea in colorectal cancer patients treated with chemotherapy regimes containing Capecitabine and 5-Fluorouracil, respectively, and between the polymorphisms rs2297595 of the DPYD gene and nausea/vomiting, rs11615 of ERCC1 and neutropenia, and rs28399433 CYP2A6 and neutropenia, in colorectal cancer patients treated with FOLFOX or XELOX as adjuvant therapy. METHOD: Colorectal cancer patients treated with chemotherapy regimes, containing Capecitabine (n = 157), 5-Fluorouracil (n = 99) were included in the study, as well as patients treated with XELOX or FOLFOX (n = 83) as adjuvant therapy. The patients included were recruited from the Doce de Octubre University Hospital and from the Gregorio Marañón General University Hospital, and signed the informed consent form. DNA was obtained from blood samples. Genotyping was carried out with SNaPshot. Contingency tables were created for analyzing the associations between the genotypes and the adverse reactions. RESULTS: None of the associations previously identified was replicated in the validation cohort. CONCLUSIONS: Pharmacogenetic studies with a limited sample size must be validated with bigger cohorts, if possible by means of multicentre studies, reducing the variables to the maximum and should never be used in clinical practice without validation.

OBJETIVO: Validar las asociaciones, encontradas previamente en tres cohortes de pacientes del Hospital General Universitario Gregorio Marañón, entre los polimorfismos rs1128503, rs2032582 y rs1045642 del gen ABCB1 con síndrome manopie y diarrea en pacientes de cáncer colorrectal tratados con regímenes que contenían capecitabina y 5-Fluorouracilo, respectivamente, y entre los polimorfismos rs2297595 del gen DPYD con nauseas/vómitos, rs11615 ERCC1 y neutropenia, y rs28399433 CYP2A6 y neutropenia en pacientes de cáncer colorrectal tratados con FOLFOX o XELOX en adyuvancia. MÉTODO: Se incorporaron al estudio pacientes de cáncer colorrectal tratados con regímenes quimioterápicos que contenían capecitabina (n = 157), 5-fluorouracilo (n = 99) y pacientes tratados en adyuvancia con XELOX o FOLFOX (n = 83). Los pacientes participantes fueron reclutados en el Hospital Universitario Doce de Octubre y en el Hospital General Universitario Gregorio Marañón tras firmar consentimiento informado. Se extrajo ADN a partir de muestras de sangre. Los genotipados se realizaron mediante SNaPshot. Se realizaron tablas de contingencia para analizar las asociaciones entre genotipos y reacciones adversas. RESULTADOS: Ninguna de las asociaciones previamente identificadas fue replicada en la cohorte de validación. CONCLUSIONES: Los estudios farmacogenéticos con un tamaño muestral limitado deben ser validados en cohortes más numerosas, a ser posible en estudios multicéntricos, reduciendo al máximo las variables y nunca deben ser utilizados en clínica sin validar.

TTD consensus document on the diagnosis and management of exocrine pancreatic cancer.

Exocrine pancreatic cancer (PC) is a very aggressive and heterogeneous tumor with several cellular signaling pathways implicated in its pathogenesis and maintenance. Several risk factors increase the risk of developing PC. Therapeutic strategies used are dictated by the extent of disease. Supportive treatment is critical because of the high frequency of symptoms. For localized disease, surgery followed by adjuvant gemcitabine is the standard. Neoadjuvant and new adjuvant chemotherapy regimens are being evaluated. Locally advanced disease should respond best guided by a multidisciplinary team. Various treatment options are appropriate such as chemotherapy alone or chemoradiotherapy with integration of rescue surgery if the tumor becomes resectable. In metastatic disease, chemotherapy should be reserved for patients with ECOG 0-1 using Folfirinox or gemcitabine plus nab-paclitaxel as the most recommended options. Several therapeutic strategies targeting unregulated pathways are under evaluation with an unmet need for biomarkers to guide management.

SEOM clinical guidelines for the adjuvant treatment of colorectal cancer 2013.

Colorectal cancer is one of the most important causes of cancer mortality worldwide. This article reviews the available evidence for optimum management of stage II and III colorectal cancer, with respect to staging, surgical and adjuvant neoadjuvant treatment.

Panitumumab and irinotecan every 3 weeks is an active and convenient regimen for second-line treatment of patients with wild-type K-RAS metastatic colorectal cancer.

PURPOSE: To evaluate the efficacy and safety profile of the combination of panitumumab and irinotecan every 3 weeks in a phase II trial as second-line treatment in patients with advanced wild-type (WT) K-RAS colorectal cancer (CRC). METHODS: Fifty-three patients received 9 mg/kg of panitumumab followed by 350 mg/m(2) of irinotecan every 21 days until disease progression, unacceptable toxicity or consent withdrawal. RESULTS: Median age of patients included was 67 years. All patients had previously received 5-fluorouracil, 84 % oxaliplatin and 8 % irinotecan as first-line treatment. Patients received a median of five infusions of panitumumab and irinotecan. On an intention-to-treat analysis, 12 patients (23 %) achieved partial responses and 22 patients (41 %) achieved disease stabilization. Median progression-free survival and overall survival were 4.5 and 15.1 months, respectively. The most frequent treatment-related severe toxicities per patient were diarrhoea (35.8 %), followed by skin rash (32.1 %), asthenia (18.9 %) and neutropenia (13.2 %). A significant association between clinical response and incidence and grade of skin toxicity was observed (p = 0.0032). CONCLUSION: This study shows that the administration of panitumumab plus irinotecan every 3 weeks is safe, active and feasible as second-line treatment in patients with advanced WT K-RAS CRC.