Spectrophotometer and ultrasound evaluation of late toxicity following breast-cancer radiotherapy

Abstract

Purpose: Radiation-induced normal-tissue toxicities are common, complex, and distressing side effects that affect 90% of patients receiving breast-cancer radiotherapy and 40% of patients post radiotherapy. In this study, the authors investigated the use of spectrophotometry and ultrasound to quantitatively measure radiation-induced skin discoloration and subcutaneous-tissue fibrosis. The study's purpose is to determine whether skin discoloration correlates with the development of fibrosis in breast-cancer radiotherapy. Methods: Eighteen breast-cancer patients were enrolled in our initial study. All patients were previously treated with a standard course of radiation, and the median follow-up time was 22 months. The treated and untreated breasts were scanned with a spectrophotometer and an ultrasound. Two spectrophotometer parameters-melanin and erythema indices-were used to quantitatively assess skin discoloration. Two ultrasound parameters-skin thickness and Pearson coefficient of the hypodermis-were used to quantitatively assess severity of fibrosis. These measurements were correlated with clinical assessments (RTOG late morbidity scores). Results: Significant measurement differences between the treated and contralateral breasts were observed among all patients: 27.3% mean increase in skin thickness (p < 0.001), 34.1% mean decrease in Pearson coefficient (p < 0.001), 27.3% mean increase in melanin (p < 0.001), and 22.6% mean increase in erythema (p < 0.001). All parameters except skin thickness correlated with RTOG scores. A moderate correlation exists between melanin and erythema; however, spectrophotometer parameters do not correlate with ultrasound parameters. Conclusions: Spectrophotometry and quantitative ultrasound are objective tools that assess radiationinduced tissue injury. Spectrophotometer parameters did not correlate with those of quantitative ultrasound suggesting that skin discoloration cannot be used as a marker for subcutaneous fibrosis. These tools may prove useful for the reduction of radiation morbidities and improvement of patient quality of life.

Breast irradiation causes pallor in the nipple‐areolar complex in women with Celtic skin type (result from the St. George and Wollongong randomised breast boost trial)

“…This study showed that breast irradiation in this predominantly Caucasian female population causes lighter NAC in 33% of patients. This result is interesting as it differs from previous reports on skin late effects, which have demonstrated increased pigmentation and melanin . This may be a reflection of the histological composition of areolar tissue to breast skin .…”

“…This result is interesting as it differs from previous reports on skin late effects, which have demonstrated increased pigmentation and melanin. 18,19 This may be a reflection of the histological composition of areolar tissue to breast skin. 13 Whether this fading phenomenon is due to vascular changes or other mechanism is unknown.…”

The Impact of Axillary Lymph Node Surgery on Breast Skin Thickening During and After Radiation Therapy for Breast Cancer

“…(18,19) In a cross-sectional study, ultrasound measurements of skin thickness strongly correlated with physician assessments of cutaneous toxicity using RTOG grading criteria. (18) Skin thickness is also a relevant concern to patients due to its association with breast texture and appearance and if persistent, may serve as an unwanted reminder of cancer treatment.…”

Hyperspectral Imaging and Classification for Grading Skin Erythema

“…In radiation therapy, erythema reactions resulting from skin exposure to ionizing radiation also known as radiation dermatitis is a common limiting factor. Unchecked, severe radiation dermatitis can lead to intense pain, skin ulcers and tissue necrosis resulting in treatment interruptions and reduced quality of life [8][9][10][11]. Early assessment of radiation induced erythema can facilitate more timely interventions; it may help reduce patient discomfort, increase compliance with treatment and improve treatment outcomes [10].…”