Stage I luminal A invasive ductal breast cancer with post-treatment cognitive symptoms

What happened, in summary

This 71-year-old Brazilian Latin American woman was diagnosed with localized invasive ductal breast cancer. Pathology showed a 2.0 × 2.0 × 1.5 cm tumor with Nottingham histologic grade 3, nuclear grade 3, mitotic index 2, absent lymphocytic infiltrate, moderate peritumoral desmoplastic reaction, and no tumor vascular invasion. Immunohistochemistry showed a luminal A profile: ER 100% positive, PR 95% positive, HER2 score 0 / negative, Ki-67 10%, and P63 negative. She underwent radical mastectomy on 23 September 2021. Hormone therapy began on 22 February 2022, with letrozole 2.5 mg daily recommended for 90 days. She also received adjuvant chemotherapy with docetaxel 75 mg and cyclophosphamide, listed in the case as Ciclofosfamide 600 mg, for 4 cycles. After treatment, she noticed memory-related cognitive difficulties. Her oncology team ruled out brain metastases before the neuropsychology evaluation and intervention. At evaluation, she had mild cognitive impairment, with MMSE 21 and MoCA 16, low verbal fluency, and a GDS-15 depression score of 8. She then received 12 sessions of transcranial direct current stimulation over 4 weeks, targeting the left dorsolateral prefrontal cortex. Each session lasted 30 minutes at 2 mA. After the protocol, MMSE remained 21, MoCA improved to 20, depression score decreased to 2, and no physical complaints or side effects were reported. Her story is best framed as survivorship after completed Stage I breast cancer treatment with supportive care for cognitive and mood symptoms. The follow-up measurements suggest improvement in daily cognitive confidence and mood, while the cancer portion of the case remained localized and already treated.