Circulating tumor cells (CTCs) in metastatic breast cancer (MBC): prognosis, drug resistance and phenotypic characterization.

BACKGROUND: the expression of ATP-binding cassette transporters on circulating tumor cells (CTCs) is predictive of response to chemotherapy in cancer patients. We tested the hypothesis that drug-resistant CTCs might have predictive value in metastatic breast cancer (MBC) and possibly retain stem-like properties. PATIENTS AND METHODS: CTCs obtained from 42 MBC patients were evaluated for multidrug-resistance-related proteins (MRPs), aldehyde dehydrogenase 1 (ALDH1), estrogen receptor α (ERα) and human epidermal growth factor receptor 2 (HER2/neu). Primary objective was to evaluate the prognostic and predictive value of CTCs profile. Secondary end points were the level of concordance in ERα and HER2/neu status between primary tumors and CTCs and the correlation in CTCs between ALDH1, drug resistance profile and number of MRPs. RESULTS: A difference in progression-free survival (PFS) was found between CTCs-positive and CTCs-negative patients. PFS was shorter in patients with a 'drug resistance' CTCs profile and in patients whose CTCs expressed two or more MRPs. No correlation was found between tumor characteristics and ALDH1. ALDH1 correlated to negative ERα and positive HER2/neu status in CTCs. The correlation between the number of MRPs expressed in CTCs and ALDH1 was statistically significant. CONCLUSION: in MBC, the presence of CTCs expressing MRPs and ALDH1 is predictive of response to chemotherapy.

[Diagnostic reliability of scintigraphy in hepatic metastases of breast cancer]. / L'attendibilità diagnostica della scintigrafia nelle metastasi epatiche da carcinoma mammario.

The authors have reviewed their experiences in determining the presence of liver metastases in 103 patients by radiocolloid scanning. The sensitivity of liver scanning proved to be quite low if the presence of focal defects of tracer's distribution was chosen as the diagnostic criterion. The inclusion of less restrictive criteria, such as liver enlargement or irregular distribution of the tracer, resulted in an higher sensitivity without lowering the predictive value of a negative scan. Using the more extensive diagnostic criterion, sensitivity, specificity and accuracy were in the range of 90%. Abnormal liver scans are common in patients classified as T3-T4 or N+ and their chances of to be "true positives" are high. Conversely, abnormal scans are seldom found in patients classified as T1-T2 or N0 and chances of "false positives" are high.