The initial hormone receptor/HER2 subtype is the main determinator of subtype discordance in advanced breast cancer: a study of the SONABRE registry

Purpose The hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) are the main parameters in guiding systemic treatment choices in breast cancer, but can change during the disease course. This study aims to evaluate the biopsy rate and receptor subtype discordance rate in patients diagnosed with advanced breast cancer (ABC). Methods Patients diagnosed with ABC in seven hospitals in 2007–2018 were selected from the SOutheast Netherlands Advanced BREast cancer (SONABRE) registry. Multivariable logistic regression analyses were performed to identify factors influencing biopsy and discordance rates. Results Overall, 60% of 2854 patients had a biopsy of a metastatic site at diagnosis. One of the factors associated with a reduced biopsy rate was the HR + /HER2 + primary tumor subtype (versus HR + /HER2- subtype: OR = 0.68; 95% CI: 0.51–0.90). Among the 748 patients with a biopsy of the primary tumor and a metastatic site, the overall receptor discordance rate was 18%. This was the highest for the HR + /HER2 + primary tumor subtype, with 55%. In 624 patients with metachronous metastases, the HR + /HER2 + subtype remained the only predictor significantly related to a higher discordance rate, irrespective of prior (neo-)adjuvant therapies (OR = 7.49; 95% CI: 3.69–15.20). Conclusion The HR + /HER2 + subtype has the highest discordance rate, but the lowest biopsy rate of all four receptor subtypes. Prior systemic therapy was not independently related to subtype discordance. This study highlights the importance of obtaining a biopsy of metastatic disease, especially in the HR + /HER2 + subtype to determine the most optimal treatment strategy.

Role of pre-metastatic niche in organ specificity of breast cancer metastasis. Influence on metastatic potential as a basis for CDK4/6-inhibition efficacy in early therapy of disseminated hormone-receptor-positive disease

Influencing the pre-metastatic niche is a very perspective cancer treatment strategy in order of preventing metastases formation. It was found that bone marrow progenitor cells and tumor cells secreting biological compounds are key components in the formation of the pre-metastatic niche. Myeloid suppressor cells (MSCs) are the main type of bone marrow cells in pre-metastatic niches. At the same time, tumor-associated chronic inflammation induces the expression of proinflammatory cytokines triggering myeloid cells differentiation into myeloid suppressor cells. When circulating tumor cells enter the circulatory channel, their interaction with immune cells is observed, which additionally influences the pre-metastatic site preparation. Studies have shown that the entire spectrum of immune cells is capable of influencing the metastasis formation by circulating tumor cells. The epithelialmesenchymal transition with the tumor cell transporting form appearence was found to be related to the function of the ZEB1 protein. Its activity is regulated by numerous signaling mechanisms at the transcriptional level, including TGFβ, Wnt and Notch. This initiates epithelial-mesenchymal transition of breast cancer cells. Zhang Z.et al. proved that CDK4/6 blocking leads ZEB1 protein stability decreasing, preventing metastasis in breast cancer in vitro and in vivo. Moreover, USP51 deubiquitinase has been identified as a target of cyclin-dependent 4/6 kinases. At the molecular level, CDK4/6 phosphorylate and activates USP51, which then influences ZEB1 deubiquitination and stabilization. A positive correlation was demonstrated between the expression of p-RB (an indicator of CDK4/6 activity), p-USP51 and ZEB1 in breast cancer samples. Thus, the CDK4/6-USP51-ZEB1 axis may play a key role in the metastasis of breast cancer. In breast cancer cells, inhibition of CDK4/6 was shown to increase the expression of E-cadherin but decrease the expression of mesenchymal markers, reducing the migratory ability and invasiveness of breast cancer cell lines. This biological effect may also explain the clinical efficacy of the CDK4/6 inhibitor Abemaciclib in early-line therapy of metastatic breast cancer as well as in adjuvant combination hormone therapy for the prevention of metastatic lesions in patients at high risk of recurrence and progression in the MONARCH E study. Besides, there were no response predictors evaluated in trials investigating CDK4/6 in breast cancer treatment and it is unknown if there any differences in treatment response according to the metastatic site. The clinical cases demonstrate abemaciclib clinical efficacy in metastatic breast cancer treatment regardless of metastatic site.

A Rare Metastatic Site of Invasive Lobular Breast Carcinoma: A Case Report

Here, we report a case of a 42-year-old female patient with left lobular breast cancer-gastric metastasis (initially misdiagnosed five years ago as an invasive ductal carcinoma) presenting with dyspepsia, weight loss, and persistent vomiting lasting for four weeks. Upper GI endoscopy revealed evidence of linitis plastica, and histological and immunocytochemical analyses of the biopsy confirmed gastric metastasis secondary to invasive lobular breast carcinoma.

Positive Association Between Location of Melanoma, Ultraviolet Signature, Tumor Mutational Burden, and Response to Anti–PD-1 Therapy

PURPOSE Emerging evidence suggests a correlation between the tumor mutational burden (TMB) and the response to programmed cell death-1 protein (PD-1) monotherapy across multiple cancer types. In skin cancers, as high TMB is mostly because of ultraviolet (UV) exposure, we hypothesized a correlation between the primary melanoma cutaneous location according to sun exposure and response to anti–PD-1 monotherapy. METHODS The aim of this study was to analyze, in advanced melanoma, the relationship between TMB, locations according to sun exposure, and response to PD-1 inhibitors. We conducted a prospective multicentric analysis, by sequencing the most recent metastatic sample before PD-1 inhibitors using FoundationOne assay. RESULTS One hundred two patients were included, with TMB available for 94 cases. In univariate and multivariate linear regression, TMB was significantly associated with sun-exposed areas of the primary melanoma location and with age (coefficients of the association with log-TMB: non-UV location, –1.05; chronic sun-exposed area, 1.12; P value for the location, < 10–5; age, 0.021 per year, P value for age, .002). Molecular UV signature present on the metastatic site was associated with higher TMB ( P = .003). Melanomas bearing a high TMB had a higher probability of response to PD-1 inhibitors compared with melanomas with a low TMB, with a dose-dependent effect following an exponential curve and a negative odds ratio of 0.40 (95% CI, 0.20 to 0.72, P = .004) between log-TMB and 6-month progression. CONCLUSION Cumulative sun exposure related to skin location and molecular UV signature present on the metastatic site appear to be relevant biomarkers directly linked to TMB. Because TMB is not yet available to all for routine clinical use, the location of the primary melanoma in a sun-exposed area may play an important role in clinical decisions regarding therapeutic choice.

Long-Term Outcomes and Causes of Death among Medullary Thyroid Carcinoma Patients with Distant Metastases

Distant metastasis is a poor prognostic factor in medullary thyroid carcinoma (MTC), but the significance of differentiating the characteristics according to the site of distant metastasis remains unclear. This study aimed to evaluate the clinical characteristics and long-term oncologic outcomes in MTC patients with distant metastasis. We identified 46 MTC patients with distant metastasis between 1994 and 2019. Clinical characteristics were compared based on the timing of the detection of distant metastasis. Additionally, survival rates following the detection of distant metastasis were evaluated to compare the clinical significance of metastatic site. The detailed causes of death were also investigated. Of the 46 patients, 15 patients (32.6%) had synchronous distant metastasis and 31 patients (67.4%) had metachronous distant metastasis. There was no clinical difference between these two groups except regarding initial surgical extent. The lung (52.2%) was the most common metastatic site, followed by the bone (28.3%), mediastinum (19.6%), liver (17.4%), adrenal gland (4.3%), brain (4.3%), kidney (2.2%), and pancreas (2.2%). Patients with bone metastasis and multisite metastasis had significantly worse prognoses than those with lung metastasis (hazard ratio: 5.42; p = 0.044 and hazard ratio: 6.11; p = 0.006). Complications due to the progression of distant metastasis, airway obstruction due to tracheal invasion, and complications related to chemotherapy were leading causes of death. In conclusion, there was no difference in clinical characteristics according to the timing of distant metastasis. Oncological outcomes differed by metastatic site.

Successful Response of Pembrolizumab Rechallenge after Radiotherapy for a Patient with Bladder Cancer of Nonresponse of Pembrolizumab First Challenge

We report a patient with advanced bladder cancer in which the primary lesion and metastatic site disappeared following the pembrolizumab therapy rechallenge after radiotherapy for bladder cancer lesion of nonresponse of pembrolizumab first challenge. A 76-year-old man with advanced bladder cancer received three courses of the chemotherapy with gemcitabine and cisplatin combination; however, the chemotherapy was stopped because of adverse events. The patient started pembrolizumab therapy; however, the effect was not observed. Radiation therapy was given to the primary lesion and pelvic lymph node metastases for the purpose of local control of the lesions. Because the primary lesion was regrowth and para-aortic lymph node metastasis appeared, pembrolizumab therapy was resumed. Thereafter, the primary lesion and metastatic site disappeared.