Clinical benefits of cetuximab retreatment in patients with metastatic colorectal (mCRC) have been reported. In the present study, the effect of cetuximab retreatment on predictive markers was investigated by evaluating the clinical benefit of initial cetuximab treatment prior to cetuximab retreatment. Between November 2012 and March 2017, 14 patients with KRAS proto‑oncogene GTPase exon 2 wild‑type mCRC who exhibited a clinical benefit (confirmed stable disease for at least 6 months or a clinical response) to an initial cetuximab‑based regimen, who received multiple lines of chemotherapy following disease progression and ultimately received a second cetuximab and irinotecan regimen, were retrospectively analyzed. For retreatment, patients received bi‑weekly irinotecan (120‑150 mg/m2) combined with cetuximab (400 mg/m2 as an initial dose, followed by 250 mg/m2, weekly). The median age of the 14 patients (11 males, 3 females) was 68 years (32‑77). The median progression‑free survival (PFS) following prior cetuximab‑based therapy was 6.6 months (range, 4.1‑18.4). Initial cetuximab treatment was administered as a first‑line treatment in 11 patients, a second‑line treatment in 1 patient and a third‑line treatment in 2 patients. The median interval time between the last cycle of initial cetuximab‑based therapy and the first cycle of cetuximab retreatment was 13.1 months (range, 6.0‑37.1). The objective response rate of cetuximab retreatment was 21.4% and the median PFS was 4.4 months (95% confidence interval, 1.4‑5.6). The Spearman's correlation coefficient for the PFS following retreatment and duration of initial cetuximab‑based regimens demonstrated a more marked correlation compared with that between the PFS following retreatment and the interval time between the two regimens (r=0.45, P=0.11 vs. r=0.08, P=0.79). Cetuximab retreatment may provide clinical benefit to patients with mCRC who were good responders with longer periods of initial cetuximab‑based therapy.

Paclitaxel is used in second-line conventional chemotherapies to manage patients with unresectable advanced gastric cancer (GC). Paclitaxel-induced peripheral neuropathy is a known adverse event leading to treatment discontinuation. Additionally, oxaliplatin which causes irreversible peripheral neuropathy is now commonly used in first-line chemotherapy for advanced GC in Japan. Thus, examining the incidence of peripheral neuropathy with paclitaxel after oxaliplatin is necessary to improve the quality of life and outcomes of patients with advanced GC in the second-line treatment setting. This prospective observational multicenter study, (which we named IVY study), will evaluate the degree of chemotherapy-induced peripheral neuropathy (CIPN) and the efficacy of second-line chemotherapy for unresectable advanced GC. A patient neurotoxicity questionnaire (PNQ) and the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) will be used to assess CIPN during the second-line treatment. The key eligibility criteria are as follows: 1) unresectable or recurrent GC histologically confirmed to be primary adenocarcinoma of the stomach, 2) age over 20 years, 3) Eastern Cooperative Oncology Group performance status score of 0–2, 4) written informed consent following full study information is provided to the patient, 5) progression or intolerance for first-line chemotherapy comprising fluorinated pyrimidine and platinum anticancer drugs (cisplatin or oxaliplatin) for advanced GC. 6) presence of evaluable lesions as confirmed using a computed tomography (CT) or magnetic resonance imaging. A total of 200 patients is considered to be appropriate for inclusion in this study. The results of this study will provide some information on CIPN with the sequential usage of oxaliplatin as first-line chemotherapy to paclitaxel as second-line chemotherapy in clinical practice. This trial is registered in the University Hospital Medical Information Network’s Clinical Trials Registry with the registration number UMIN000033376 (Registered 11 July 2018).

Introduction: No previous studies have evaluated clinical outcomes, such as BRAF/KRAS mutation profiles and microsatellite instability (MSI) statuses, of ovarian metastases of colorectal cancers (CRCs). This retrospective study aimed to clarify the clinicopathological features of CRC in women with respect to somatic mutation profiles, and to evaluate the efficacy of oophorectomy for ovarian metastases of CRC.