The identification of challenges in tissue collection for biomarker studies: the Q-CROC-03 neoadjuvant breast cancer translational trial experience.

One of the major challenges in biomarker development is the collection of tumor tissue of adequate quality for analysis. A prospective clinical trial was initiated to collect tissues from triple negative breast cancers prior to and after neoadjuvant chemotherapy in order to study the mechanisms of chemoresistance. Sixty patients had pre-chemotherapy biopsies performed by either a surgeon or a radiologist, while those with residual tumor after chemotherapy had research-only biopsies and/or surgical samples collected in liquid nitrogen, RNA-later and formalin. We examined each core for tumor cellularity, stromal content, and necrosis after which, RNA and DNA extraction was performed. We found that biopsies collected with ultrasound guidance were more likely to contain tumor than those collected by the surgeon. Patient reluctance to undergo research-only biopsies after chemotherapy was not a problem. Pre-chemotherapy tumor biopsies frequently did not contain any tumor cells (15%) or did not have ≥50% tumor content (63%). Indeed, 50% of patients had at least 2 pre-chemotherapy core biopsies with <50% tumor content. After chemotherapy, 30% of biopsy or surgical samples in patients with incomplete response did not contain any tumor. Finally, RNA-later not only made histopathological assessment of tumor content difficult, but yielded less DNA than fresh snap frozen samples. We recommend that high-quality tissue procurement can be best accomplished if at least three image-guided core biopsies be obtained per sample, each of these cores be examined for tumor cellularity and that at least some of them be freshly snap frozen in liquid nitrogen.

Prognostic and predictive value of circulating tumor DNA during neoadjuvant chemotherapy for triple negative breast cancer.

Response to neoadjuvant chemotherapy (NAC) in triple negative breast cancer (TNBC) is highly prognostic and determines whether adjuvant chemotherapy is needed if residual tumor is found at surgery. To evaluate the predictive and prognostic values of circulating tumor DNA (ctDNA) in this setting, we analyzed tumor and serial bloods from 26 TNBC patients collected prior, during, and after NAC. Individual digital droplet PCR assays were developed for 121 variants (average 5/patient) identified from tumor sequencing, enabling ctDNA detection in 96% of patients at baseline. Mutant allele frequency at baseline was associated with clinical characteristics. Levels drastically fell after one cycle of NAC, especially in patients whose tumors would go on to have a pathological complete response (pCR), but then rose significantly before surgery in patients with significant residual tumor at surgery (p = 0.0001). The detection of ctDNA early during treatment and also late at the end of NAC before surgery was strongly predictive of residual tumor at surgery, but its absence was less predictive of pCR, especially when only TP53 variants are considered. ctDNA detection at the end of neoadjuvant chemotherapy indicated significantly worse relapse-free survival (HR = 0.29 (95% CI 0.08-0.98), p = 0.046), and overall survival (HR = 0.27 95% CI 0.075-0.96), p = 0.043). Hence, individualized multi-variant ctDNA testing during and after NAC prior to surgery has prognostic and predictive value in early TNBC patients.

Hemodynamic effects of early versus late glucocorticosteroid administration in experimental septic shock.

Recent findings in human septic shock suggest that glucocorticosteroids can limit and even reverse hemodynamic disturbances and dependence on catecholamines. In a rodent model of hypotensive and hypokinetic septic shock, we investigated the effects of early or late dexamethasone administration on hemodynamics, response to catecholamines, and cardiac beta-adrenergic signalling. As compared with sham-operated rats, the untreated septic rats displayed significant arterial hypotension and reduced aortic blood flow. However, in vivo pressor response to epinephrine and phenylephrine was not different among sham and septic animals. Conversely, the chronotropic response to isoproterenol was significantly attenuated in septic animals. Steroid-treated septic animals displayed complete reversal of hypotension, improvement in aortic blood flow, and reduced plasma lactate and nitrite/nitrate concentrations as compared with untreated septic animals. The number of myocardial beta-adrenergic receptors and in vivo isoproterenol-stimulated myocardial cAMP content were similar in sham and septic animals. Glucocorticosteroids, although not changing these patterns, significantly decreased the receptors affinity when administered late, but not early. In this model of septic shock, hemodynamic abnormalities may not be related to adrenergic receptor desensitization. That steroids can improve them suggests that they could act mainly distal to adrenergic receptors, for instance, on myocardial and vascular smooth fiber contraction properties through mechanisms probably including inducible nitric oxide synthase inhibition.

Waiting for a breast biopsy. Psychosocial consequences and coping strategies.

OBJECTIVE: The aim of this pilot/feasibility study was to describe the experience of women presenting with a suspicious mammogram who are waiting for a breast biopsy and to identify those at risk for distress. METHODS: Participants (n=25) were interviewed at two time points: immediately after being put on the waiting list (T1) and again immediately before their biopsy approximately 6 weeks later (T2). Self-report measures of distress and coping were used. Perceived personal risk of a positive biopsy finding and information needs were assessed through open-ended questions. RESULTS: Distress levels were high in this sample. Using cognitive-avoidant coping strategies, being employed, history of previous biopsies, and having a family history of breast cancer were associated with greater distress. Perceived personal risk of a positive biopsy finding was overestimated in one half of the cases and was correlated with greater distress. CONCLUSION: Waiting period between suspicious mammogram and breast biopsy may be a time of high distress for many women.