Change in HER-2/neu Status from Negative to Positive following Treatment in Breast Cancer: A Case Report

Abstract

Introduction: Approximately 25–30% of breast cancers are assumed to be HER-2/neu positive. It is well known that HER-2/neu-positive cancers after treatment with trastuzumab can become HER-2/neu negative. Change in HER-2/neu status from negative to positive following treatment has not been well studied. We describe a patient with inflammatory breast cancer who was initially HER-2/neu negative but became positive after treatment. A 59-year-old postmenopausal white female saw her surgeon for violaceous discoloration of the left breast for 4 months. The surgeon palpated a mass measuring 6 cm in the patient’s left breast. Additionally, there was violaceous discoloration involving two thirds of the breast. Biopsy of the breast mass and skin revealed inflammatory breast cancer. The tumor was estrogen receptor positive, progesterone receptor positive and HER-2/neu negative. The patient was given four cycles of chemotherapy with cyclophosphamide, doxorubicin and docetaxol. She subsequently underwent a mastectomy, excision of the skin over the chest wall and axillary node dissection. Of the axillary lymph nodes, 14/14 were involved. The tumor was still estrogen receptor positive and progesterone receptor positive, but HER-2/neu was 2+ by immunohistochemistry and amplified at 3.3 as detected by fluorescent in situhybridization. The patient received trastuzumab along with chemotherapy followed by radiation therapy and letrozole. She is currently receiving trastuzumab and letrozole in the adjuvant setting and appears to be doing well. Conclusion: A breast cancer which was initially HER-2/neu negative can become positive following treatment. Therefore, re-biopsy may be necessary during the course of treatment of breast cancer to re-assess the HER-2/neu status. This gives the clinician the opportunity to include drugs like trastuzumab and lapatinib in the treatment of patients with a transformation to HER-2/neu-positive cancer.

Epidemiological characterization of hormonal receptor profiles and associated histopathological characteristics in Rwandan women with breast cancer: a retrospective study

“…Although there is no target therapy HER2 breast cancer patients in Rwanda, the use of hormonal therapy was showing effective in patients expressing HR(s). This is may be linked to the previous studies that reported the change from HER2 + to HER2- [34], leading to negative patients' prognosis [44], or with no impact on the prognosis [45]. The worse situation of lacking the HER2 inhibitor targeted therapy, such as trastuzumab to manage HER2 breast cancer patients [46] could be likely resolved by the conversion of HER2+, the opposite situation could also happen which yet require to include the HER2 targeted therapy in the treatment options.…”

“…The expression of HER2 breast cancer was also found in 31% of the study population. This nding showed that HER2 positivity is slightly falling in the range of reported literatures (15-30%) [9,[33][34][35][36][37]. For instance, Borgquist et al…”

“…The increased number of HER2 breast cancer could come from recurrence, and being negative for HER2 does not mean for life. As the gene encoded by HER2 is associated with fast grow of the tumor which are also more likely to spread, as well as to recur [41]; studies have reported a shift from HER2-to HER2+, suggesting a re-examination of the HER2 status regularly or at any recurrence of breast cancer [34]. Moreover, when it happen to express either or both HRs, along with HER2 breast cancer, the effectiveness of tamoxifen is consequently hindered [33].…”

Influence of Neoadjuvant Chemotherapy on HER2/neu Status in Invasive Breast Cancer

“…In contrast, Taucher et al analyzed tumors of patients on anthracycline/taxane-based neoadjuvant therapy regimens and found no significant change of HER2/neu expression, 13 and Sivarajan et al reported a case showing conversion from HER2/neu negative to positive. 27 Thus, the findings in reported NAC studies are conflicting with respect to HER2/neu status and response to anthracyclines. However, based on our results we recommend that the HER2/neu IHC score should be reevaluated in posttreatment tissue, as clinical decisions regarding adjuvant cytotoxic treatment after NAC are frequently based on immunohistochemical analysis performed on surgical specimens.…”

Epidemiological characterization of hormonal receptor profiles and associated histopathological characteristics in Rwandan women with breast cancer: a retrospective study

“…The expression of HER2 breast cancer was also found in 31% of the study population. This finding showed that HER2 positivity is slightly falling in the range of reported literatures (15-30%) [8,[30][31][32][33][34]. For instance, Borgquist et al [33] [30].…”