Abstract
Background: Pregnancy-associated breast cancer is defined as breast cancer diagnosed during pregnancy, lactation, or up to one year postpartum, and represents the most common malignancy in this period. Physiological breast changes during pregnancy may delay diagnosis, particularly in aggressive subtypes such as triple-negative breast cancer.
Aim: To report a case of triple-negative invasive ductal carcinoma diagnosed at the end of pregnancy, highlighting diagnostic and therapeutic challenges.
Methods: This is a case report based on the review of medical records, imaging and pathological findings, combined with a narrative review of the literature on breast cancer during pregnancy.
Case Report: A 39-year-old primigravida woman, followed in a high-risk prenatal program, presented with a painless right breast mass in the third trimester. Breast ultrasound revealed a suspicious lesion (BI-RADS 4B), and core needle biopsy confirmed triple-negative invasive ductal carcinoma, Nottingham grade II. After delivery, tumor progression was observed, leading to the indication of neoadjuvant chemotherapy followed by planned breast-conserving surgery.
Conclusion: Pregnancy-associated breast cancer demands a high level of clinical suspicion, and any persistent breast mass should be promptly investigated regardless of gestational age. Multidisciplinary management is essential to ensure timely treatment and optimize maternal and neonatal outcomes.
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