Complication Avoidance of Reconstruction Implant Radiation Therapy (CARIT): A Retrospective Case-Cohort Analysis

PURPOSE/OBJECTIVE(S)

Patients are increasingly offered implant-based reconstruction prior to radiotherapy. However, it is unclear if the radiation treatment technique itself impacts upon toxicity. We performed this study to compare outcomes following implant-based reconstruction amongst breast cancer patients treated with a standard radiotherapy technique that irradiates the entire chest wall versus a novel technique which uses a smaller clinical target volume (CTV) to spare the implant. Need for corrective surgery, capsular contracture, and cosmetic outcomes were evaluated, with the hypothesis that the novel technique would result in fewer adverse outcomes and less need for corrective surgery.

MATERIALS/METHODS

A retrospective case-cohort analysis of 57 patients who had post-mastectomy, implant-based reconstruction was conducted. Patients with invasive mammary carcinoma (IMC) or ductal carcinoma in-situ (DCIS) who were treated either with the novel radiotherapy technique (n = 26) or standard PMRT (n = 31) were included. Patient demographics such as age, BMI, TNM stage, implant size, hormone receptor status, and radiation course was collected. Primary endpoint was the need for corrective surgery within two years and cosmetic outcomes, measured using the Baker Classification Scale for capsular contracture and the Modified Harvard Harris Cosmetic Scale. Secondary endpoint was radiation-induced toxicity measured using the National Cancer Institute Common Terminology Criteria for Adverse Events (NCI CTCAE). Cosmesis and toxicity were evaluated at 3 months post-radiation, 1 year, and after 13 months. Unpaired t-tests were used to compare need for corrective surgery, cosmesis (Baker Grade 2 or higher and Harvard Harris "Good" or worse), and toxicity (NCI CTCAE Grade 2 or higher).

RESULTS

For the primary endpoint, need for corrective surgery, there was no significant difference between the novel and standard groups (two-sided p = 0.378, CI -0.38-0.14). The other primary endpoint of cosmesis, measured with the Baker scale and Harvard Harris, was also not significantly different (two-sided p = 0.147, CI -0.06-0.45), with the Harvard Harris cosmesis differences remaining insignificant across the 3 month, 1 year, and greater than 13 month periods (two-sided p = 0.854, 0.351, 0.468, respectively). The secondary endpoint, toxicity, was not significantly different between the novel and standard PMRT groups across 3 months and 1 year time periods (two-sided p = 0.328, 0.323, respectively). We will also be reporting the analysis for predictive factors related to toxicity, need for corrective surgery and cosmesis.

CONCLUSION

Compared with standard PMRT, the novel technique was not significantly different in rates of reoperation, toxicity and cosmetic outcomes. Better understanding the factors involved in PMRT outcomes for breast cancer patients with implant-based reconstructions will aid in the development of standardized approaches to treating the breast cancer patient population.

Characterization and reliability of internet resources on pulmonary rehabilitation for individuals with chronic lung disease

BACKGROUND

Individuals with lung disease commonly use the internet as a source of health information on pulmonary rehabilitation (PR). The objective of this study was to characterize internet resources on PR, and to assess the content, readability, and quality of patient-directed PR resources.

METHODS

The first 200 websites for the search term 'pulmonary rehabilitation resources and exercise' were analyzed on Google, Yahoo, and Bing. Website content was assessed based on 30 key components of PR from the 2013 and 2021 international consensus statements. Website quality was determined using DISCERN, JAMA benchmarks, and Global Quality Scale (GQS).

RESULTS

66 unique PR websites were identified with the two most common categories being scientific resources (39%) and foundation/advocacy organizations (33%). The average reading level of websites was 11 ± 3. PR content varied significantly across websites (mean range 13.4-21.5). Median DISCERN total score and GQS score were 4 (IQR 3-4) and 3.5 (IQR 2-4), respectively, representing moderate-good quality. Foundation/advocacy websites had higher DISCERN and GQS scores compared to other websites.

CONCLUSION

Foundation/advocacy websites had the highest quality and reliability metrics; however, the higher-than-recommended reading levels may compromise patient comprehension and utilization. This study provides critical insight on the current state of online PR health-related information.

Are Radiation Target Volumes for Postmastectomy Radiation Therapy Too Large? Initial Report of the Complication Avoidance of Reconstruction Implant Radiation Therapy (CARIT) Study

Following mastectomy for breast cancer, women may choose implant-based reconstruction for many reasons, such as cosmesis, self-identity, and the ability to wear particular items of clothing. However, postmastectomy radiation therapy (PMRT) can compromise these cosmetic goals, including as much as a 40% loss of implant rate. To minimize the risk of radiation toxicity, it is important to consider how clinical target volumes (CTVs) can be optimized in PMRT to preserve the implant and reduce complications. Typically, guidelines from organizations such as the Radiation Oncology Group are used, which include regions previously encompassed by tangential fields. This includes all structures below the pectoralis muscle, such as the chest wall, where the risk of recurrence is negligible; this technique often requires incidental inclusion of portions of the lung and heart plus circumferential radiation of the implant. We present the preliminary single institution case series of a technique of complication avoidance of reconstruction implant radiation therapy, called CARIT, where the chest wall, and a large proportion of the implant, is not irradiated. In a retrospective review of 30 cases in which CARIT has been attempted, it was found that 24% of patients treated required a second surgery due to Baker grade III/IV capsular contracture. Using the Modified Harvard Harris Cosmetic Scale, 66.5% of patients had cosmetic outcomes rated as "good" or "excellent". CARIT could offer a technique to reduce complications in postmastectomy implant-based reconstruction patients, with our next steps focusing on improving dosimetry, and formally comparing the cosmesis and tumor control aspects with commonly used techniques.