Purpose: The objective of this study was to evaluate the role of (18)F-FDG PET/CT in predicting overall survival in inflammatory breast cancer patients undergoing neoadjuvant chemotherapy.
Methods: Included in this retrospective study were 53 patients with inflammatory breast cancer who had at least two PET/CT studies including a baseline study before the start of neoadjuvant chemotherapy. Univariate and multivariate analyses were performed to assess the effects on survival of the following factors: tumor maximum standardized uptake value (SUVmax) at baseline, preoperatively and at follow-up, decrease in tumor SUVmax, histological tumor type, grade, estrogen, progesterone, HER2/neu receptor status, and extent of disease at presentation including axillary nodal and distant metastases.
Results: By univariate analysis, survival was significantly associated with decrease in tumor SUVmax and tumor receptor status. Patients with decrease in tumor SUVmax had better survival (P = 0.02). Patients with a triple-negative tumor (P = 0.0006), a Her2/neu-negative tumor (P = 0.038) or an ER-negative tumor (P = 0.039) had worse survival. Multivariate analysis confirmed decrease in tumor SUVmax and triple-negative receptor status as significant predictors of survival. Every 10% decrease in tumor SUVmax from baseline translated to a 15% lower probability of death, and complete resolution of tumor FDG uptake translated to 80% lower probability of death (P = 0.014). Patients with a triple-negative tumor had 4.11 times higher probability of death (P = 0.004).
Conclusion: Decrease in tumor SUVmax is an independent predictor of survival in patients with inflammatory breast cancer undergoing neoadjuvant chemotherapy. Further investigation with prospective studies is warranted to clarify its role in assessing response and altering therapy.