Lacrimal Duct Obstruction during Trastuzumab Emtansine (KADCYLA^®, T-DM1) Therapy after Breast Cancer Surgery—A Report of Two Cases—

Abstract

Two women in their 60s who were diagnosed with breast cancer developed lacrimal duct obstruction during adjuvant trastuzumab emtansine (T-DM1) therapy. Case 1 involved a patient with Stage II B right breast cancer who received neoadjuvant doxorubicin and cyclophosphamide (AC), followed by trastuzumab, pertuzumab, and docetaxel therapy before surgery. During the fourth course of T-DM1 treatment, the patient experienced bilateral epiphora and discomfort. Ophthalmological evaluation revealed bilateral punctal stenosis. Lacrimal duct tube insertion led to rapid symptom improvement, and she was able to complete T-DM1 therapy. Case 2 involved a patient with Stage I left breast cancer who received neoadjuvant AC and trastuzumab plus docetaxel, followed by surgery. During the sixth T-DM1 course, the patient experienced bilateral blurred vision and epiphora. Ophthalmological examination revealed corneal and lacrimal duct disorders. The symptoms improved rapidly after insertion of the lacrimal duct tube, allowing therapy completion. These cases suggest that T-DM1 may cause lacrimal duct disorders. Early symptom recognition and timely ophthalmological intervention can prevent cancer treatment interruption.