Abstract PS2-05-05: The Anatomic Basis of Thoracodorsal Artery Perforator-based Flap: Cadaveric and Angiographic Study

Abstract Introduction: Breast cancer surgery has shifted towards breast conservation surgery. Perforator-based flaps play a pivotal role. The thoracodorsal artery perforator-based (TDAP) flap is one such. In TDAP, varied amount of skin and subcutaneous fat can be used. It can reach any quadrant of the breast. It can even be converted to a musculocutaneous flap, if a larger volume is required. In this study, the anatomical and vascular basis of TDAP were analysed using computed tomography angiographic (CTA) and cadaveric dissection (CD). Methods: A prospective observation study was carried out over 2 years in AIIMS, New Delhi. TDAP was dissected in 10 cadavers (20 sides). As part of metastatic workup, CTA was done in 23 locally advanced breast cancer (LABC) patients along with bone scan. Fresh, Theil cadavers, cadavers ≥ 18 years of age, and female BC patients >18 years were included. Injury/ scarring of chest wall, previous axillary surgery and cadavers/ patients <18 years were excluded. Primary objective was to determine course, precise localization and diameter of TDAPs. Secondary objective was to analyse and compare pattern of distribution of TDAPs: Dominant (DP) and Non-Dominant (NDP), in CD and CTA. Perforators were marked in sequence as TDAP 1, 2, 3 and so on. Analysis parameters of TDAP, in CD and CTA were distance from apex of axilla, distance from anterior border of latissimus dorsi (LD), diameter of perforator at its entry into muscle and perforator’s length. DPs and NDPs were analysed. Data was recorded in MS Excel and analysed in SPSS v23. Descriptive statistics were elaborated as means/standard deviations, medians/IQRs for continuous variables. Frequencies and percentages for categorical variables, group comparisons of continuously distributed data using independent sample ‘t’ test, Chi-squared test for group comparisons of categorical data, Paired t-test for paired analysis for continuous variables and Wilcoxon Signed Rank test for non-parametric data were used. Results: A total of 52 TDAPs (20 in males and 32 in females) in cadavers and 57 TDAPs in 23 LABC patients were identified. Spatial distribution-wise (CD), 20 (38.5%) were TDAP1, 20 (38.5%) were TDAP2 and 12 (23.1%) TDAP3. From CTA, 45 (78.9%) were TDAP1 and 8 (14%) were TDAP2. Only 2 perforators were found as TDAP 3 and 4 in CTA. At least 1 DP was identified in CD and CTA. TDAP detection frequency and distance from the anterior border of LD were more in CD. In CD and CTA, the mean length of TDAP and distance from the apex of the axilla were comparable. The diameter of the perforator was significantly more in CTA. Conclusion: TDAPs have a consistent distribution pattern, adequate length and vessel calibre, when analysed in CD and CTA. The anatomical and vascular basis of TDAP (DPs and NDPs) are important for better perforator-based reconstructions. Citation Format: R. Mukherjee, S. K. Pattashanee, B. K. Singh, A. Krishna, S. Soren, D. Kandasamy, S. V. The Anatomic Basis of Thoracodorsal Artery Perforator-based Flap: Cadaveric and Angiographic Study [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2025; 2025 Dec 9-12; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2026;32(4 Suppl):Abstract nr PS2-05-05.