Spatial transcriptomics and the anatomical pathologist: Molecular meets morphology.

In recent years anatomical pathology has been revolutionised by the incorporation of molecular findings into routine diagnostic practice, and in some diseases the presence of specific molecular alterations are now essential for diagnosis. Spatial transcriptomics describes a group of technologies that provide up to transcriptome-wide expression profiling while preserving the spatial origin of the data, with many of these technologies able to provide these data using a single tissue section. Spatial transcriptomics allows expression profiling of highly specific areas within a tissue section potentially to subcellular resolution, and allows correlation of expression data with morphology, tissue type and location relative to other structures. While largely still research laboratory-based, several spatial transcriptomics methods have now achieved compatibility with formalin-fixed paraffin-embedded tissue (FFPE), allowing their use in diagnostic tissue samples, and with further development potentially leading to their incorporation in routine anatomical pathology practice. This mini review provides an overview of spatial transcriptomics methods, with an emphasis on platforms compatible with FFPE tissue, approaches to assess the data and potential applications in anatomical pathology practice.

Ethnicity, Immunity, and Outcomes: Biology versus Socioeconomic Status.

Substantial advances in our understanding of breast cancer disease biology have led to marked improvements in cancer outcomes over the past two decades. These advances have largely focused on women from developed, high-income countries and as a result, significant disparities exist. In this issue, Bauer and colleagues provide new insight into the breast cancer immune microenvironment from women across geographic regions in sub-Saharan Africa, despite inherent infrastructure limitations. The study amassed data from 1,497 women from sub-Saharan Africa, and 117 women from Germany with breast cancer, suggesting regional variation in immune composition but with no significant prognostic impact. These important findings require validation in large, codesigned prospective studies to fully understand the impact of biology, ethnicity, and socioeconomic status on breast cancer outcomes. See related article by Bauer et al., p. 720 (2) .

Triple-negative breast cancer: recent treatment advances.

Triple-negative breast cancer (TNBC) is a breast cancer subtype renowned for its capacity to affect younger women, metastasise early despite optimal adjuvant treatment and carry a poor prognosis. Neoadjuvant therapy has focused on combinations of systemic agents to optimise pathological complete response. Treatment algorithms now guide the management of patients with or without residual disease, but metastatic TNBC continues to harbour a poor prognosis. Innovative, multi-drug combination systemic therapies in the neoadjuvant and adjuvant settings have led to significant improvements in outcomes, particularly over the past decade. Recently published advances in the treatment of metastatic TNBC have shown impressive results with poly (ADP-ribose) polymerase (PARP) inhibitors and immunotherapy agents. Immunotherapy agents in combination with traditional systemic chemotherapy have been shown to alter the natural history of this devastating condition, particularly in patients whose tumours are positive for programmed cell death ligand 1 (PD-L1).

Efficacy of late line pertuzumab with trastuzumab and chemotherapy in HER2-positive metastatic breast cancer: An Australian case series.

BACKGROUND: Pertuzumab, when combined with trastuzumab and chemotherapy, is a highly active human epidermal growth factor receptor 2 (HER2), targeting agent in the neoadjuvant, adjuvant and first-line metastatic HER2-positive breast cancer setting. The efficacy of late-line (after first/second-line) pertuzumab in combination with trastuzumab and chemotherapy is unknown. AIMS: To establish pertuzumab efficacy by performing an audit of patients who received pertuzumab after first-line HER2 directed therapy. We sought to establish whether efficacy differed by clinicopathological factors. METHODS: The primary endpoint was progression-free survival (PFS) and the secondary endpoint, overall survival (OS). Clinicopathological factors, PFS and OS data were collated and clinicopathological factors associated with PFS were evaluated using Cox regression models. RESULTS: Fourteen women were identified. Six (43%) had hormone receptor (HR) negative and eight (57%) had HR-positive, metastatic HER2-positive breast cancer. Median follow up was 22.8 months, median prior lines of therapy were 5 (range: 1-9). Median time from diagnosis of metastatic disease to receiving pertuzumab was 4.5 years (range: 4.2-5.8). All patients received initial chemotherapy with pertuzumab and trastuzumab (taxane-based 71%). Median PFS was 9 months (95% confidence interval [CI]: 7-not estimable [NE]) and median OS was not reached (95% CI, 16 months-NE). Univariable analysis demonstrated that HR-negative patients had a significantly longer PFS than HR-positive patients (hazard ratio = 0.11; 95% CI, 0.01-0.88; P = 0.04). CONCLUSION: This small cases series reports a favorable PFS and OS for pertuzumab with trastuzumab and chemotherapy in the later line metastatic setting. This finding warrants further study.

Impact of access to novel therapies on the initial management of castrate-resistant prostate cancer: an Australian multicentre study.

BACKGROUND: The impact of regulatory approvals of new therapies for castration-resistant prostate cancer (CRPC) in Australia is unclear. AIMS: To determine if changes in novel therapy access in Australia affected how clinicians initially managed men with newly diagnosed CRPC. METHODS: Data from patients diagnosed with CRPC from 2013 to 2016 across three Australian hospitals were retrospectively collected. Baseline clinicopathological factors and initial management decision at the time of CRPC development (early treatment (ET) vs deferred treatment (DT)) were recorded. Categorical variables between cohorts were compared by Chi-squared analysis. Cox regression analysis was performed to assess the impact of CRPC diagnosis year on time to commencing life-prolonging systemic treatment (TTT). RESULTS: Our study identified 137 CRPC patients, with 126 (92%) patients receiving life-prolonging systemic treatment. The median age was 73 years. The initial management decision was DT in 71 (52%) patients and ET in 66 (48%) patients. There was a significant shift from DT to ET during the study period (2013-2014: DT 61% vs ET 33%; 2015-2016: DT 39% vs ET 67%; P = 0.004), with a rise in novel androgen receptor signalling inhibitor use and simultaneous reduction in first-generation antiandrogen use at CRPC development. Each successive CRPC diagnosis year was associated with shorter TTT on univariate analysis (HR: 1.5, 95% CI: 1.3-1.7, P < 0.001). CONCLUSION: Over time, clinicians are favouring earlier introduction of life-prolonging systemic treatment at the development of CRPC. This trend is largely driven by substantial uptake of novel androgen receptor signalling inhibitors as the preferred initial treatment for CRPC patients.

A Phase Ib Dose-Escalation and Expansion Study of the BCL2 Inhibitor Venetoclax Combined with Tamoxifen in ER and BCL2-Positive Metastatic Breast Cancer.

Venetoclax, a potent and selective BCL2 inhibitor, synergizes with endocrine therapy in preclinical models of ER-positive breast cancer. Using a phase Ib 3 + 3 dose-escalation and expansion study design, 33 patients with ER and BCL2-positive metastatic disease (mean prior regimens, 2; range, 0-8) were treated with daily tamoxifen (20 mg) and venetoclax (200-800 mg). Apart from uncomplicated "on-target" lymphopenia, no dose-limiting toxicities or high-grade adverse events were observed in the escalation phase (15 patients), and 800 mg was selected as the recommended phase II dose (RP2D). In the expansion phase (18 patients), few high-grade treatment-related adverse events were observed. For 24 patients treated at the RP2D, the confirmed radiologic response rate was 54% and the clinical benefit rate was 75%. Treatment responses were preempted by metabolic responses (FDG-PET) at 4 weeks and correlated with serial changes in circulating tumor DNA. Radiologic responses (40%) and clinical benefit (70%) were observed in 10 patients with plasma-detected ESR1 mutations. SIGNIFICANCE: In the first clinical study to evaluate venetoclax in a solid tumor, we demonstrate that combining venetoclax with endocrine therapy has a tolerable safety profile and elicits notable activity in ER and BCL2-positive metastatic breast cancer. These findings support further investigation of combination therapy for patients with BCL2-positive tumors.See related commentary by Drago et al., p. 323.This article is highlighted in the In This Issue feature, p. 305.