Vemurafenib-induced radiation recall dermatitis: case report and review of the literature.

The cutaneous effects of BRAF (serine/threonine protein kinase B-raf) inhibitors such as vemurafenib remain poorly defined. Rash, squamous cell carcinoma, keratoacanthoma and photosensitivity are the most common grade 2 or 3 adverse events observed in clinical trials. We here report the case of a patient with a BRAF V600E mutated metastatic melanoma who developed severe radiation recall dermatitis 6 weeks after completing radiotherapy. Vemurafenib treatment had been initiated 1 week before the development of dermatitis because of rapidly progressing disease. Upon topical treatment of the affected skin areas, clinical symptoms regressed over a period of 2 months, although vemurafenib was continuously administered. As our case goes in line with other reports, we believe that physicians should be aware of this additional cutaneous side effect of vemurafenib and that continuation of the treatment is safe when close clinical control and interdisciplinary management can be provided.

Lymph node metastasis of squamous cell carcinoma from an unknown primary: impact of positron emission tomography.

This study was performed to assess the potential benefit of positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) in patients with cervical metastasis of squamous cell carcinoma from an unknown primary tumour. Eighteen patients with cervical metastasis of squamous cell carcinoma from an unknown primary who were assessed by physical examination including transnasal fibre-endoscopy and radiological work-up with computed tomography were included in this prospective tertiary referral centre cohort study. The results of the search for the primary with rigid panendoscopy of the upper aerodigestive tract were compared to the evaluation with FDG PET. Panendoscopy revealed a primary tumour in 8/18 (44%) patients. PET accurately diagnosed five of these eight primary tumours, and gave one false positive and three false negative scans, resulting in a sensitivity of 63%, a specificity of 90%, an accuracy of 78%, a positive predictive value of 83% and a negative predictive value of 75%. Small primaries or primaries in areas with physiologically increased FDG uptake can be missed with PET owing to the limited resolution of the camera (approximately 5 mm). Our study in a small number of patients suggests that PET does not provide benefit in terms of detecting additional primary tumours if applied in addition to extensive clinical work-up. Considering its high specificity, PET could be of value as an initial evaluation instrument, reserving the need for extensive work-up to patients with negative scans.

Assessment of clinical utility of 18F-FDG PET in patients with head and neck cancer: a probability analysis.

The purpose of this study was to calculate disease probabilities based on data of patients with head and neck cancer in the register of our institution and to perform a systematic review of the available data on the accuracy of PET in the primary assessment and follow-up of patients with head and neck cancer. The pre-test probability of head and neck cancer among patients in our institutional data registry was assessed. Then the published literature was selected and appraised according to a standard protocol of systematic reviews. Two reviewers independently selected and extracted data on study characteristics, quality and accuracy. Accuracy data were used to form 2 x 2 contingency tables and were pooled to produce summary receiver operating characteristic (ROC) curves and summary likelihood ratios for positive and negative testing. Finally post-test probabilities were calculated on the basis of the pre-test probabilities of this patient group. All patients had cytologically or histologically proven cancer. The prevalence of additional lymph node metastases on PET in staging examinations was 19.6% (11/56), and that of locoregional recurrence on restaging PET was 28.6% (12/42). In the primary assessment of patients, PET had positive and negative likelihood ratios of 3.9 (2.56-5.93) and 0.24 (0.14-0.41), respectively. Disease probabilities were therefore 49.4% for a positive test result and 5.7% for a negative test result. In the assessment of recurrence these values were 3.96 (2.8-5.6) and 0.16 (0.1-0.25), resulting in probabilities of 49.7% and 3.8%. PET evaluation for involvement of lymph nodes had positive and negative likelihood ratios of 17.26 (10.9-27.3) and 0.19 (0.13-0.27) for primary assessment and 11.0 (2.93-41.24) and 0.14 (0.01-1.88) for detection of recurrence. The probabilities were 81.2% and 4.5% for primary assessment and 73.3% and 3.4% for assessment of recurrence. It is concluded that in this clinical setting the main advantage of PET is the ability to reliably rule out the presence of disease in both staging and restaging. Further research is required to derive probabilities for individual patients from sequential testing as applied in the diagnostic work-up of patients with head and neck cancer.