Radiation-induced oesophagitis in breast cancer: Factors influencing onset and severity for patients receiving supraclavicular nodal irradiation.

AIM: The aim of this study was to determine dosimetric factors, such as mean dose and oesophageal length, which may influence the incidence and severity of oesophagitis in breast cancer patients receiving radiotherapy to the supraclavicular nodes. METHODS: This was a single-arm prospective observational study. Toxicity grading was undertaken twice weekly to determine the onset of grade 2 oesophagitis in consecutive patients prescribed IMRT to the breast or chest wall and supraclavicular fossa (SCF) nodes. Recorded variables included mean and maximum doses to the oesophagus, oesophageal length and pharynx length within the treatment area. Multivariate logistic regression and Fishers' exact test were used with a 0.05 significance level to compare the onset of grade 2 oesophagitis with these variables. RESULTS: A total of 77 patients were included in the study. Twenty-four (31%) patients reported grade 2 oesophagitis. There was a higher incidence of grade 2 oesophagitis in patients receiving a mean oesophageal dose of ≥31 Gy compared to those receiving < 31 Gy (18/24 versus 6/24, respectively, P = 0.025). There was a significant difference in the onset of grade 2 toxicity in patients who had ≥ 1 cm of pharynx included in SCF fields compared with those with <1 cm (15/24 versus 9/24, respectively, P = 0.0116). The odds ratios for developing grade 2 oesophagitis were 3.2 (95% CI = 1.05-9.62, P = 0.04) for a mean dose of ≥31 Gy and 3.4 (95% CI = 1.19-9.5, P = 0.022) for ≥1 cm of pharynx in the SCF field. CONCLUSION: By limiting the mean dose to the irradiated oesophagus to <31 Gy during the planning process and ensuring that <1 cm of pharynx is included in the radiation field, oesophageal toxicity may be minimised.

Contouring consensus guidelines in breast cancer radiotherapy: Comparison and systematic review of patterns of failure.

Adequate coverage of sites harbouring potential microscopic disease is paramount, where the clinical decision has been made to include regional lymph node radiotherapy for patients with breast cancer. This must be achieved in balance with minimising dose to normal tissues. Several international consensus guidelines detailing clinical target volumes (CTVs) are available, but there is currently no agreement as to which is most appropriate for a given clinical situation. Contouring guidelines are beneficial for routine practice and essential for clinical trial quality assurance. The aims of this study were as follows: to provide a single point of comparison of four commonly used contouring guidelines, including one used in a current Trans-Tasman Radiation Oncology Group trial; and to undertake a systematic review of existing studies which map sites of breast cancer recurrence against contouring guidelines. Two international consensus guidelines (European Society for Radiotherapy and Oncology, and Radiation Therapy Oncology Group) were compared with two clinical trial guidelines (TROG 12.02 PET LABRADOR and the Proton/Photon trial NCT02603341 RADCOMP). Comprehensive literature search for patterns of failure studies was undertaken using Embase and Pubmed. We detail the small but significant differences between the breast consensus guidelines, particularly the supraclavicular (SCF) and internal mammary chain CTVs. Seven series were found mapping recurrence patterns. These results are discussed in the context of the contouring guidelines. Several studies found the SCF CTV is the area at greatest risk of geographical 'miss'. This review will facilitate further discussion about guideline selection and modification, particularly for future clinical trials in Australia and New Zealand.

Radiotherapy for breast cancer associated with a cutaneous presentation of systemic mastocytosis-a case report and literature review.

Ionizing radiation therapy is a common adjuvant therapy for individuals undergoing surgery for breast cancer. There are many well-recognized acute and chronic cutaneous reactions that can vary in severity, course and duration. We present a rare cutaneous manifestation of systemic mastocystosis, in a 59-year-old female who underwent adjuvant radiotherapy following local excision of ductal carcinoma in situ.