Early assessment of neoadjuvant chemotherapy by FEC-courses of locally advanced breast cancer using 99mTc-MIBI

Response assessment at neoadjuvant (preoperative) chemotherapy of locally advanced breast cancer using clinical examination and mammography is insensitive. Mammoscintigraphy with 99mTc-MIBI was studied for the prediction of response at such therapy before finishing the chemotherapy cycles.

Chemotherapy was given as repeated courses of 5-fluorouracil, epirubicin and cyclophosphamide (FEC). In 1 patient group (n = 23), the tumor uptake relative to surrounding breast tissue and lung tissue at SPECT examination after finishing neoadjuvant chemotherapy was compared with the examination made before chemotherapy. In another group (n = 30), a similar comparison after the first therapy cycle (mean 19 days) with a baseline examination was made. Histologic examination of the resected tumors was made.

After finishing chemotherapy, there was a strong reduction of the relative tumor activity, while there was no correlation with therapy effect as assessed by histology. After one therapy course, there was no significant reduction of the relative tumor uptake.

Scintigraphy with 99mTc-MIBI demonstrated the response after finished neoadjuvant chemotherapy of breast cancer using FEC-courses. It cannot be used to predict a therapy response after one therapy course.