Back to 2026 Abstracts
Radiate the Flap or Expander? Comparative Outcomes in Immediate Versus Delayed-Immediate DIEP Flap Reconstruction Among Postmastectomy Patients: A TriNetX Database Study
Michael L. Chang
*1, Emily L. Isch
2, Devi Schwartz
1, John Winton
1, Matthew Jenkins
3, David Kim
3, Andrew Newman
3, Heather McMahon
31Sidney Kimmel Medical College at Thomas Jefferson University, Kennett Square, PA; 2Department of Surgery, Thomas Jefferson University, Philadelphia, PA; 3Department of Plastic Surgery, Thomas Jefferson University, Philadelphia, PA
Background: The optimal management of deep inferior epigastric perforator (DIEP) flap breast reconstruction in postmastectomy radiation therapy (PMRT) patients remains debated. Immediate reconstruction (IR) may offer psychological and aesthetic benefits, while the delayed-immediate reconstruction (DIR) approach may reduce radiation-associated complications. Current comparative studies yield mixed results, are limited to short-term outcomes, and do not control for flap type, radiation therapy, or delayed approaches. This study aims to compare short and long-term complication and revisional rates between IR and DIR DIEP flap reconstruction in PMRT patients.
Methods: A retrospective cohort study was conducted utilizing data from TriNetX, a multinational database. Data was queried from 2013 to January 2026 and patients were categorized into IR and DIR cohorts. Propensity score matching controlled for patient characteristics. Outcomes included rates and incidence of flap compromise, hematoma, seroma, infection, wound dehiscence, venous thromboembolism (VTE), fat necrosis, revisional procedures and hypertrophic scarring within 7 days, 90 days, 1 year, and 2 years of DIEP flap reconstruction.
Results: The search identified 505 and 786 patients in the IR and DIR cohorts, respectively, resulting in 422 pairs after matching (n=844). IR had similar rates of flap compromise, 90-day hematoma, seroma, infection, wound dehiscence, and VTE compared to DIR (p>0.05). One-year fat necrosis incidence was comparable. At 1 year follow-up, IR had lower cumulative incidence of revisional procedures and fat grafting (p<0.01). At 2 year follow-up, IR had higher cumulative incidence of breast fat necrosis (p=0.0047), similar total revisional procedures, and lower cumulative incidence of revisional fat grafting (p=0.0001) compared to DIR.
Conclusion: The complications and revisional rates in IR and DIR do not preclude the application of either approach. Plastic surgeons should counsel patients on how long-term risks impact personal goals, balancing aesthetic priorities with oncologic safety.
Comparison of Short- and Long- Term Outcomes of IR and DIR DIEP flap breast reconstruction among PMRT patients
| Outcome Category / Variable | IR Cohort (n=422) | DIR Cohort (n=422) | Risk ratio (95% CI) | p-value |
| 7-day Complications | |
| 3-day Arterial/Venous Thrombosis | 26 (6.16%) | 31 (7.35%) | 0.84 (0.51-1.39) | 0.58 |
| Flap failure requiring operative re-exploration, n (%) | 12 (2.84%) | 21 (4.97%) | 0.77 (0.49-1.22) | 0.246 |
| 90-day Complications | |
| Hematoma, n (%) | <10 (<2.4%)* | <10 (<2.4%)* | 1.0 (1.0-1.0)* | 1.000 |
| Seroma, n (%) | 16 (3.80%) | 13 (3.09%) | 1.23 (0.60-2.53) | 0.571 |
| Surgical Site Infection, n (%) | 25 (5.94%) | 17 (4.04%) | 1.47 (0.81-2.68) | 0.205 |
| Wound Dehiscence, n (%) | 42 (9.98%) | 42 (9.98%) | 1.00 (0.66-1.50) | 1.000 |
| VTE, n (%) | 20 (4.75%) | 13 (3.08%) | 1.53 (0.78-3.05) | 0.214 |
| 1-year Outcomes | |
| Breast Fat Necrosis, n (%) | 81 (19.19%) | 57 (13.51%) | 1.42 (1.04-1.94) | 0.026 |
| Total Revisional Procedures, n (%) | 176 (41.71%) | 199 (47.16%) | 0.88 (0.76-1.03) | 0.111 |
| NAC Reconstruction, n (%) | 44 (10.43%) | 34 (8.06%) | 1.29 (0.85-1.98) | 0.235 |
| Fat Grafting, n (%) | 71 (16.83%) | 111 (26.30%) | 0.64 (0.49-0.83) | 0.0008 |
| Hypertrophic Scarring/Fibrosis, n (%) | 148 (35.07%) | 148 (35.07%) | 1.00 (0.83-1.20) | 1.000 |
| 2-year Outcomes | |
| Breast Fat Necrosis, n (%) | 109 (25.83%) | 68 (16.11%) | 1.60 (1.22-2.10) | 0.0005 |
| Total Revisional Procedures, n (%) | 232 (55.0%) | 234 (55.5%) | 0.99 (0.88-1.12) | 0.890 |
| NAC Reconstruction, n (%) | 57 (13.51%) | 51 (12.09%) | 1.12 (0.79-1.59) | 0.536 |
| Fat Grafting, n (%) | 95 (22.51%) | 133 (31.52%) | 0.71 (0.57-0.90) | 0.003 |
| Hypertrophic Scarring/Fibrosis, n (%) | 182 (43.13%) | 165 (39.1%) | 1.10 (0.94-1.30) | 0.234 |
*Patient counts less than 10 were reported as <10 due to data privacy.
Models adjusted for BMI, tissue expander size, and axillary irradiation. OR > 1 indicates higher odds with early exchange.
Back to 2026 Abstracts
Models adjusted for BMI, tissue expander size, and axillary irradiation. OR > 1 indicates higher odds with early exchange.
