Ultrasound B-lines for detection of late lung fibrosis in breast cancer patients after radiation therapy

Background and purpose. Radiation therapy (RT) for breast cancer after conservative surgery can be life-saving but remains associated with significant late side effects, including lung fibrosis, detected by chest CT. Aim of this study was to assess whether lung ultrasound (LUS) may detect late lung fibrosis through the biomarker of B-lines. Materials and methods. We evaluated 30 women (median age 67 years, range 46-80 years) about 3-8 years after RT (follow up 38-101 months, median 58 months) for left (n = 12) or right (n = 18) breast cancer (stage 1, n = 24; stage 2, n = 6), treated with total dose 40.5 – 50.00 Gy with/without boost dose). In all, both treated and contralateral hemithorax were evaluated. LUS was performed and B-lines evaluated with a 28-region antero-lateral scan, from second to fifth intercostal spaces, along the mid-axillary, anterior axillary, mid-clavicular, and arasternal lines. In each space, the B-lines were counted from 0 = black lung to 10 = white lung. The sum of B-lines in all spaces generated the B-line score of each hemithorax. Results. Median B-line score was higher in the irradiated site than in the contralateral control hemithorax (9, 1st-3rd quartiles: 2-23 vs 3, 1st-3rd quartiles: 1-4; P median value of 2.7 Gy) were associated with more B-lines when compared to lower doses (< 2.7 Gy): 9 vs 5, p < 0.001. Conclusion. RT in female breast cancer survivors is associated with increase in B-lines in the targeted hemithorax, likely due to lung fibrosis, and related to the lung mean dose. LUS can provide a simple “echo-marker” of lung fibrosis.

Nasopharyngeal cancer: the impact of guidelines and teaching on radiation target volume delineation

Target volume delineation in the radiation treatment of nasopharyngeal cancer is challenging due to several reasons such as the complex anatomy of the site, the need for the elective coverage of definite anatomical regions, the curative intent of treatment and the rarity of the disease, especially in non-endemic areas. We aimed to analyze the impact of educational interactive teaching courses on target volume delineation accuracy between Italian radiation oncology centers. Only one contour dataset per center was admitted. The educational course consisted in three parts: (1) The completely anonymized image dataset of a T4N1 nasopharyngeal cancer patient was shared between centers before the course with the request of target volume and organs at risk delineation; (2) the course was held online with dedicated multidisciplinary sessions on nasopharyngeal anatomy, nasopharyngeal cancer pattern of diffusion and on the description and explanation of international contouring guidelines. At the end of the course, the participating centers were asked to resubmit the contours with appropriate corrections; (3) the pre- and post-course contours were analyzed and quantitatively and qualitatively compared with the benchmark contours delineated by the panel of experts. The analysis of the 19 pre- and post-contours submitted by the participating centers revealed a significant improvement in the Dice similarity index in all the clinical target volumes (CTV1, CTV2 and CTV3) passing from 0.67, 0.51 and 0.48 to 0.69, 0.65 and 0.52, respectively. The organs at risk delineation was also improved. The qualitative analysis consisted in the evaluation of the inclusion of the proper anatomical regions in the target volumes; it was conducted following internationally validated guidelines of contouring for nasopharyngeal radiation treatment. All the sites were properly included in target volume delineation by &gt;50% of the centers after correction. A significant improvement was registered for the skull base, the sphenoid sinus and the nodal levels. These results demonstrated the important role that educational courses with interactive sessions could have in such a challenging task as target volume delineation in modern radiation oncology