A Young Case of Neoadjuvant Taxane Monotherapy for Breast Cancer toward pCR-Quadruple Neoplasms, Pairing Uterine Sarcoma

Abstract

Abstract A 41-year-old female presented with a walnut-sized lump in her right breast. Half a year ago, she underwent a curative resection of low grade endometrial stromal sarcoma (LGESS/StageIA, total hysterectomy+bilateral salpingo-oophorectomy). Ultrasound(US) revealed a localized breast tumor (2.7cm). The Result of her breast biopsy showed invasive ductal carcinoma (solid tub.ca. ER+/PgR-/HER2-/grade3/Ki67 90%)/cT2N0M0, StageIIA. Neoadjuvant chemotherapy: paclitaxel monotherapy (80mg/m2 once weekly for 12 weeks) was performed with response-guided imaging scan(MRI/US) to avoid the anthracycline toxicity due to pretreatment of leukemia in her teens. Tumor shrinkage shown after 4 times and further therapeutic response indicated high sensitivity to taxane. Minimal hypoechoic area suspected residual lesions or scar tissue after 9 times. Late in the course of therapy, dose reduction (80mg/m2x10 times, 70 mg/m2x2) was required for peripheral neuropathy(G2). The promising antitumor activity and acceptable adverse drug reactions let her achieve whole cycle chemotherapy and maintain QOL. Imaging scan showed no residual tumor. Partial mastectomy was performed and the pathologic complete response was confirmed. Aromatase inhibitor is being considered as adjuvant endocrine therapy. Genetic counseling will be helpful and we are looking into genetic testing. The risk of developing a secondary cancer from previous cytotoxic treatments, and the certain predispositions like hereditary factor should be taken into account. Past history 15y. acute lymphoblastic leukemia BCP-ALL/chemo-1st CR (toxic drug DNR/ADM/CPM)+prophylactic cranial irradiation(18Gy). 28y. tongue cancer -non relapse/partial glossectomy+defect repair (left forearm flap). Hepatitis B/C carrier. Gynecologic 10y. menarche, teenage. menses resumption after chemo, 36y. myomectomy, 37y. delivery (daughter). Family history two females/breast cancer (fourth-degree relative/onset age, unconfirmed).