Mitosis in circulating tumor cells stratifies highly aggressive breast carcinomas

Abstract

BackgroundEnumeration of circulating tumor cells (CTCs) isolated from the peripheral blood of breast cancer patients holds promise as a clinically relevant, minimally invasive diagnostic test. However, CTC utility has been limited as a prognostic indicator of survival by the inability to stratify patients beyond general enumeration. In comparison, histological biopsy examinations remain the standard method for confirming malignancy and grading malignant cells, allowing for cancer identification and then assessing patient cohorts for prognostic and predictive value. Typically, CTC identification relies on immunofluorescent staining assessed as absent/present, which is somewhat subjective and limited in its ability to characterize these cells. In contrast, the physical features used in histological cytology comprise the gold standard method used to identify and preliminarily characterize the cancer cells. Here, we superimpose the methods, cytologically subtyping CTCs labeled with immunohistochemical fluorescence stains to improve their prognostic value in relation to survival.MethodsIn this single-blind prospective pilot study, we tracked 36 patients with late-stage breast cancer over 24 months to compare overall survival between simple CTC enumeration and subtyping mitotic CTCs. A power analysis (1-β = 0. 9, α = 0.05) determined that a pilot size of 30 patients was sufficient to stratify this patient cohort; 36 in total were enrolled.ResultsOur results confirmed that CTC number is a prognostic indicator of patient survival, with a hazard ratio 5.2, p = 0.005 (95 % CI 1.6–16.5). However, by simply subtyping the same population based on CTCs in cytological mitosis, the hazard ratio increased dramatically to 11.1, p < 0.001 (95 % CI 3.1–39.7).ConclusionsOur data suggest that (1) mitotic CTCs are relativity common in aggressive late-stage breast cancer, (2) mitotic CTCs may significantly correlate with shortened overall survival, and (3) larger and more defined patient cohort studies are clearly called for based on this initial pilot study.Electronic supplementary materialThe online version of this article (doi:10.1186/s13058-016-0706-4) contains supplementary material, which is available to authorized users.

Sequential Tracking of PD-L1 Expression and RAD50 Induction in Circulating Tumor and Stromal Cells of Lung Cancer Patients Undergoing Radiotherapy

“…In a small group of 10 healthy controls, no CAMLs, CTCs, nor EMTCTCs were found. This is in agreement with our previous studies (1,6,(10)(11)(12)(13)(14). Patients then had a second follow-up sample (T1) taken 2 to 3 weeks after radiotherapy initiation or after the last fraction for SBRT patients.…”

“…An alternative issue may be that many CTC technologies do not differentiate the EMTCTC subpopulation from the CellSearch CTC population (i.e., PDCTCs), or make any mention of CStCs (3,4,6,7,16,17,(47)(48)(49). These methods describe a BBB approach that differentiates CAMLs and the PDCTC/EMTCTC subpopulations by well-defined intrinsic biological indicators, that is, EMTCTCs lose EpCAM and downregulate cytokeratin (6,10,11,13,14,43). This differentiation appears to allow for more specific analysis, whereby CTCs with separate clinical and biological attributes can be analyzed independently or in conjunction when analyzing clinically relevant biomarkers.…”

“…cytokeratin positivity and DAPI-positive nuclei with malignant pathologic criteria, classified as the CellSearch subtype of CTC (1,6,(10)(11)(12)(13)(14). EMTCTCs are CD45 negative with a diffuse cytokeratin signal and a DAPI-positive nucleus with abnormal criteria, as defined previously (1, 6-9, 12, 13).…”

“…We have previously described the defining characteristics of the two most common CTC subtypes found in cancer patients (PDCTCs and EMTCTCs), and for CAML identification (1,6,(10)(11)(12)(13)(14). For this study, only intact PDCTCs, EMTCTCs, and CAMLs were characterized ( Fig.…”

“…Recently, we have identified a prevalent CStC subtype, cancerassociated macrophage-like cells (CAMLs), using a nonaffinity microfiltration-based method that captures both CTCs and CAMLs and allows for parallel analysis of these cancer-specific circulating cell subtypes (1,(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16). CAMLs are recently defined circulating myeloid-derived stromal cells, found in all the stages of invasive malignancy and in various solid malignancies [e.g., breast, prostate, non-small cell lung carcinoma (NSCLC), and pancreatic; refs.…”