YES1 as a Therapeutic Target for HER2-Positive Breast Cancer after Trastuzumab and Trastuzumab-Emtansine (T-DM1) Resistance Development.

Trastuzumab-emtansine (T-DM1) is a therapeutic agent molecularly targeting human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (MBC), and it is especially effective for MBC with resistance to trastuzumab. Although several reports have described T-DM1 resistance, few have examined the mechanism underlying T-DM1 resistance after the development of acquired resistance to trastuzumab. We previously reported that YES1, a member of the Src family, plays an important role in acquired resistance to trastuzumab in HER2-amplified breast cancer cells. We newly established a trastuzumab/T-DM1-dual-resistant cell line and analyzed the resistance mechanisms in this cell line. At first, the T-DM1 effectively inhibited the YES1-amplified trastuzumab-resistant cell line, but resistance to T-DM1 gradually developed. YES1 amplification was further enhanced after acquired resistance to T-DM1 became apparent, and the knockdown of the YES1 or the administration of the Src inhibitor dasatinib restored sensitivity to T-DM1. Our results indicate that YES1 is also strongly associated with T-DM1 resistance after the development of acquired resistance to trastuzumab, and the continuous inhibition of YES1 is important for overcoming resistance to T-DM1.

Risk factors of local recurrence following implant-based breast reconstruction in breast cancer patients.

BACKGROUND: The number of patients desiring implant-based breast reconstruction has been increasing. While local recurrence is observed in patients with breast reconstruction, only a few reports have focused on the risk factors for local recurrence and the prognosis after developing local recurrence. METHODS: We analyzed 387 patients who underwent implant-based breast reconstruction during the period from 2004 to 2017 in Hiroshima City Hospital. We retrospectively examined the risk factors for local recurrence and the outcomes of patients developing such recurrence after implant-based breast reconstruction. RESULTS: The median follow-up time was 59 months. The local recurrence rate was 3.1% (n = 12). The most common reason for detecting local recurrence was a palpable mass. Four patients with local recurrence had recurrence involving the skin just above the primary lesion and needle biopsy tract. All patients with local recurrence received surgery and systemic therapy and most patients received radiation therapy, all have remained free of new recurrence to date. Multivariate analysis showed lymphatic vessel invasion (HR, 6.63; 95% CI, 1.40-31.36; p = 0.017) and positive or < 2 mm vertical margin (HR, 9.72; 95%CI, 1.23-77.13; p = 0.047) to be associated with significantly increased risk of local recurrence. CONCLUSIONS: The risk factors for local recurrence following implant-based breast reconstruction were lymphatic vessel invasion and positive or < 2 mm vertical margin. Removal of the skin just above the primary lesion and needle biopsy tract and adjuvant radiation therapy might improve local outcomes. Patients with local recurrence following implant-based breast reconstruction appear to have good outcomes with appropriate treatment.

Nab-Paclitaxel Followed by 5-Fluorouracil, Epirubicin and Cyclophosphamide in Neoadjuvant Chemotherapy for Resectable Breast Cancer: A Phase II Trial.

BACKGROUND: The aim of this phase II study was to evaluate combined nab-paclitaxel (nab-PTX) with sequential anthracycline-based therapy as a neoadjuvant chemotherapy. METHODS: We enrolled 41 patients with advanced breast cancer (stage IIA - IIIC). All patients were to receive three-weekly nab-PTX (260 mg/m2) for four cycles followed by three-weekly 5-fluorouracil, epirubicin and cyclophosphamide (FEC) for four cycles. Trastuzumab administration was permitted in human epidermal growth factor receptor 2 (HER2)-positive patients. RESULTS: The overall pathological complete response (pCR) rate was 24% (10 of 41). In patients with luminal A, luminal B (HER2-), luminal B (HER2+), triple-negative and HER2, the pCR rates were 0% (0/2), 7% (1/14), 42% (3/7), 25% (4/16) and 100% (2/2), respectively. The most significant toxicities of nab-PTX were grade 2/3 peripheral sensory neuropathy (24%) and grade 3/4 neutropenia (26%). Febrile neutropenia was not observed in any patient. The most significant toxicities of FEC were grade 3/4 neutropenia (24%) and grade 3 febrile neutropenia (9%). One patient died of sepsis secondary to pneumonia during FEC treatment. CONCLUSIONS: Neoadjuvant chemotherapy using nab-PTX with trastuzumab every 3 weeks followed by FEC was suitably tolerated and associated with a high pCR rate of 55% for patients with HER2-positive breast cancer.

Evaluation of Prognosis of Juvenile Differentiated Thyroid Carcinoma.

Differentiated thyroid carcinoma (DTC) in juvenile patients is often an extensive and aggressive disease with a high frequency of recurrence. However, the prognosis is excellent, with a low mortality rate even when advanced disease is present, although prognostic factors and treatment strategy remain uncertain. Between April 2004 and March 2017, 33 juvenile patients (< 30 years old) were diagnosed with DTC and treated at our institution. We retrospectively investigated prognosis and factors including sex, reason for discovery, treatment, pathological factors and treatment progress to clarify the risk factors. All patients underwent curative surgical treatment. Pathologically, lymph node metastasis was identified in 25 patients (75%). Thirteen patients (39%) had bilateral cervical metastasis. In addition, 9 (27%) had more than 10 metastatic lymph nodes. The 2 patients with more than 20 metastatic lymph nodes were treated with radioactive iodine (RAI). Five patients (15%) had local recurrences and received surgery. There have been no further recurrences or deaths. However, no factors were determined to significantly predict the recurrence of juvenile DTC. Local recurrent disease was treated with surgery and/or RAI until remission, and survival was excellent in juvenile DTC.