Feasibility of implementation of the early tumor shrinkage as a potential predictive marker to daily clinical practice in patients with RAS wild type metastatic colorectal cancer, treated with cetuximab - a non-interventional observational study.

BACKGROUND: With the aim to show the feasibility of early tumor shrinkage (ETS) concept implementation into daily clinical practice in the Czech Republic, a non-interventional, multicentric, single arm, prospective study in real world set-up was performed. MATERIAL AND METHODS: The study objectives were to explore the time interval from the treatment starting date to the date of the first radiographic control (TFRC) and evaluate the proportion of patients who achieved ≥ 20% tumor regression within the first 8 weeks of first-line therapy, in the real-world settings. RESULTS: The medians of TFRC in all individual participating centers were > 12 weeks (range 14.0-36.4 weeks). TFRC ≤ 8 weeks was reported for only 3% of patients in the cohort with first-line therapy, and there were only 3 patients (1%) who achieved tumor regression of ≥ 20% by day 60 (8.6 weeks). CONCLUSION: These findings indicate that the basic time parameter of ETS could not realistically be employed in routine oncology care of patients with metastatic colorectal cancer (mCRC) in the Czech Republic, unless there would be a strict request to perform TRFC by week 8 since the initiation of the therapy. In addition, the frequency of objective tumor response to first-line therapy with cetuximab + chemotherapy was evaluated. Based on the relative regression in the sum of diameters of measurable metastatic lesions, unconfirmed partial responses were achieved in 42.4 % and unconfirmed complete response in 8.6% of patients, altogether corresponding to the overall response rate of 51% with first-line therapy. The frequency of responses was higher among patients with left than right sided primary tumors. It seems that the regimen of cetuximab/FOLFOX might be more active in frontline therapy of right sided RAS wild type mCRC than cetuximab/FOLFIRI.

Phytomenadione pre-treatment in EGFR inhibitor-induced folliculitis.

BACKGROUND: Targeted oncology therapy with inhibitors of epidermal growth factor receptor is associated with numerous cutaneous side effects. Acneiform eruptions are the most frequent skin toxicities reported. They may lead to impairment of patients' quality of life and sometimes may even become severe enough to necessitate the interruption or cessation of therapy. OBJECTIVE: To assess the possible effect of topical phytomenadione (vitamin K1 ) pre-treatment in diminishing the extent and severity of acne-like follicular rash associated with epidermal growth factor receptor inhibitor therapy. METHODS: A series of 20 patients with colorectal cancer or head and neck cancer were pre-treated with phytomenadione cream (0.05% in seven patients and 0.1% in 13 patients), starting morning before the first infusion of cetuximab or panitumumab, and followed up for the development of therapy-associated folliculitis. The cream was prepared from phytomenadione solution added to a hydrophilic cream base, oil in water, to obtain the concentration of 0.05% or 0.1%. RESULTS: Majority of patients (15 out of 20, 75%) pre-treated with phytomenadione cream experienced only mild, grade I acneiform eruptions. Five patients (25%) had grade II rash, which included two of seven patients pre-treated with 0.05% phytomenadione cream and three of 13 patients who used 0.1% phytomenadione cream. Topical phytomenadione cream was well tolerated and no abnormalities in blood coagulation were observed. CONCLUSIONS: Topical pre-treatment with phytomenadione cream might become useful in epidermal growth factor inhibitor-associated acneiform eruptions.

Cetuximab-induced cutaneous toxicity.

BACKGROUND: Epidermal growth factor receptor inhibitors are recently utilized by oncologists in advanced cases of certain malignancies. However, these agents are associated with numerous cutaneous adverse reactions. OBJECTIVE: To systematically review the cutaneous toxicity of cetuximab-treated patients. METHODS: An analysis of a series of 24 patients (20 men and 4 women) treated with cetuximab (12 patients with head and neck cancer and 12 patients with colorectal cancer) was performed with respect to relevant clinical characteristics. RESULTS: A total of 22 patients (91.7%) developed pustular or maculopapular follicular eruption, often referred to as acneiform rash. One patient (4.2%) developed paronychia in the course of cetuximab therapy. All patients with head and neck cancer had a combination treatment with radiotherapy and experienced radiation dermatitis accompanied by skin xerosis. Anaphylactic reaction was observed in three patients (12.5%). CONCLUSIONS: The most frequent cutaneous side effect reported in this series was acneiform eruption. The authors observed that all women with acneiform rash had only limited facial involvement, whereas all but one man experienced more widespread lesions of the face, the back and the chest. We found no association between the extent and severity of cutaneous eruptions (grade 1 vs. grade 2) and patients' response to therapy.