A case of vasculitis in a breast cancer patient treated with T-DM1

First reported case of ANCA-associated vasculitis induced by oxaliplatin, capecitabine, and trastuzumab

A 68-year-old male, who was undergoing XELOX plus trastuzumab therapy for gastric cancer, developed proteinuria, hematuria, and progressive increase in creatinine after 3 months. Subsequently, the patient also experienced hemoptysis, nasal bleeding. Chest CT examination shown pulmonary hemorrhage. The MRI of the nasopharynx ruled out nasopharyngeal cancer recurrence. The MPO and PR3 were elevated, and renal biopsy confirmed ANCA-related vasculitis, which affected the lungs, kidneys, and nasopharynx. Based on the review of the patient''s medical history and medication, it is believed that ANCA-related vasculitis was caused by XELOX plus trastuzumab chemotherapy, but it is difficult to confirm which specific drug caused it. After stopping XELOX plus trastuzumab chemotherapy, glucocorticoids and cyclophosphamide was given, the patient''s pulmonary hemorrhage and nasal bleeding stopped, and the lung lesions were absorbed. The renal function also improved. The patient later experienced pulmonary infection again, and tNGS indicated Legionella pneumophila and pulmonary tuberculosis infection. Despite anti-infection treatment, steroid dose was rapidly reduced. Ultimately, the patient gave up on treatment and eventually died.

The first reported case of trastuzumab induced interstitial lung disease associated with anti-neutrophil cytoplasmic antibody vasculitis - A case report and a prospective cohort study on the usefulness of neutrophil derived biomarkers in monitoring vasculitis disease activity during follow-up

Targeted therapies against human epidermal growth factor receptor 2 (HER2) are associated with increased interstitial lung disease (ILD). Trastuzumab, lapatinib, pertuzumab, and trastuzumab emtansine have markedly extended HER2 breast cancer survival but current knowledge on how these HER2-targeted agents induce interstitial lung disease is still poorly defined due to limited cases in the literature. Physicians mostly managed this complication by dose interruption, dose de-escalation, or discontinuation with success. In 2019, the FDA had granted accelerated approval on trastuzumab deruxtecan (T-Dxd) in HER2 breast cancer in the late line setting. Severe ILD incidence rate was over ten percent and led to fatal outcomes in 2.2% of patients in the T-Dxd trial. Searching for biomarkers to detect ILD incidence before it becomes clinically fulminant or for treatment response monitoring is of high clinical value. A Case of life-threatening trastuzumab-induced ILD was encountered in our facility. The ILD was confirmed to be antineutrophil cytoplasmic antibody (ANCA) pulmonary capillaritis. The biomarker of neutrophil extracellular traps (NETs), serum MPO-DNA complex, showed a good correlation with the clinical severity. Soon after B cell depleting agent rituximab usage, the serum MPO-DNA outperformed ANCA autoantibody and maintained its correlation with clinical severity. In addition to the trastuzumab-induced ILD case, a prospective cohort in our facility also confirmed the usefulness of MPO-DNA in monitoring vasculitis activity. We postulated that upfront testing with biomarkers of vasculitis during HER2 targeted treatment with high ILD incidence may be beneficial in the future.

Adverse Events of Trastuzumab Emtansine (T-DM1) in the Treatment of HER2-Positive Breast Cancer Patients

The human epidermal growth factor receptor 2 (HER2) is commonly associated with poor prognosis and is overexpressed in approximately 15-20% of all breast cancers. The introduction of HER2-targeted therapies led to significant improvement in the prognosis of patients with HER2-positive breast cancer, for both early and advanced disease. These targeted therapies include the antibodies trastzumab and pertuzumab, the tyrosine kinase inhibitor lapatinib, and the antibody-drug conjugate trastuzumab emtansine (T-DM1). T-DM1 combines the anti-tumor activity of trastuzumab with that of DM1, a highly potent derivative of the anti-microtubule agent maytansine, resulting in increased anti-tumor activity. Notably, this agent has been demonstrated to be safe and is associated with low toxicity rates. However, maytansinoid, the cytotoxic component of T-DM1, does have the potential to induce various adverse events, particularly radiation necrosis, when used in combination with stereotactic radiosurgery. In this review, we aimed to summarize the current literature regarding T-DM1 safety and toxicity, with special emphasis on the existing landmark studies.