High resolution dermal ultrasound (US) combined with superficial radiation therapy (SRT) versus non-image guided SRT or external beam radiotherapy (XRT) in early-stage epithelial cancer: a comparison of studies

Abstract

Background To compare the effectiveness of high-resolution dermal ultrasound (US) guided superficial radiotherapy (SRT) to non-image-guided radiotherapy in the treatment of early-stage Non-Melanoma Skin Cancer (NMSC). Methods A high-resolution dermal ultrasound (US) image guided form of superficial radiation therapy (designated here as US-SRT) was developed in 2013 where the tumor configuration and depth can be visualized prior to, during, and subsequent to treatments, using a 22 megahertz (MHz) dermal ultrasound (US) with a doppler component. We previously published the results using this technology to treat 2917 early-stage epithelial cancers showing a high local control (LC) rate of 99.3%. We compared these results with similar American studies from a comprehensive literature search used in an article/guideline published by American Society of Radiation Oncology (ASTRO) on curative radiation treatment of basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and squamous cell carcinoma in-situ (SCCIS) lesions from 1988 to 2018. Only U.S. based studies with greater than 100 cases with similar patient/lesion characteristics and stages treated by external beam, electron, or superficial/orthovoltage radiation therapy were included in the criteria for selection. The resultant 4 studies had appropriate comparable cases identified and the data analyzed/calculated with regard to local control. Logistic regression analysis was performed comparing each study to US-SRT individually and collectively with stratification by histology (BCC, SCC, and SCCIS). Results US-SRT LC was found to be statistically superior to each of the 4 non-image-guided radiation therapy studies individually and collectively (as well as stratified by histology subtype) with p-values ranging from p < 0.0001 to p = 0.0438. Conclusions Results of US-SRT in local control were statistically significantly superior across the board versus non-image-guided radiation modalities in treatment of epithelial NMSC and should be considered a new gold standard for treatment of early-stage cutaneous BCC, SCC, and SCCIS.

Updated Results of 3,050 Non-melanoma Skin Cancer (NMSC) Lesions in 1725 Patients Treated with High Resolution Dermal Ultrasound-Guided Superficial Radiotherapy, A Multi-institutional Study

“…Almost all lesions had minimal or mild toxicity scores (RTOG 0, 1, 2). Our updated results support that IGSRT, with longer follow-up, continue to offer a high local control rate felt to be comparable to the best surgical techniques (14) (15) and continues to be an effective noninvasive, non-surgical treatment modality for NMSC with its major advantages of avoiding the pitfalls of surgery clinically, cosmetically, physiologically and psychologically. These updated results validate our prior statement that IGSRT should be a primary non-surgical option presented to patients for treatment of their early-stage NMSC lesions.…”

“…Two recent studies, a metanalysis and a logistic regression analysis, compared IGSRT studies to large well run SRT/XRT studies without image guidance. Both analyses found that the LC rates for the IGSRT studies were statistically superior to the non-image-guided SRT/XRT studies (14), (15). The image-guided component of SRT utilizes a 22 megahertz (MHz) dermal ultrasound with color doppler to visualize the superficial depth of the skin.…”

Skin ultrasonography and magnetic resonance; new clinical applications and instrumentation

“…Yu et al. reported 99.3% cure of cutaneous squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) utilizing IG‐SRT in a study of 2917 patients 5,6 . Furthermore, Zemtsov while proposing Appropriate Use Criteria (AUC) for SRT emphasized in his recommendations the importance of utilization of HFUS while performing SRT 7 .…”

Diagnostic value of high‐frequency ultrasound (HFUS) in evaluation of subcutaneous lesions

“…With the development of high‐frequency ultrasound (HFUS), the resolution is continuously improving, thus dermatological lesions can be well evaluated 21–23 . In evaluation of skin subcutaneous lesions, HFUS is now used for image guided superficial radiation therapy and Doppler modality is starting to be utilized in evaluation of vasculature of all skin lesions 24–26 …”

“…[21][22][23] In evaluation of skin subcutaneous lesions, HFUS is now used for image guided superficial radiation therapy and Doppler modality is starting to be utilized in evaluation of vasculature of all skin lesions. [24][25][26] It should be noted that, so far as we know, most of the previous studies regarding the usefulness of HFUS were with a visible change of appearance. The appearance of lesions can provide additional diagnostic information.…”