Assessment of the Circulating Tumor Cells and Microsatellite Instability in Colorectal Cancer Patients: Prognostic and Diagnostic Value.

BACKGROUND: Microsatellite instability (MSI) and circulating tumor cells (CTCs) play important roles in the diagnosis, prognosis and management of colorectal cancer (CRC) patients. METHODS: CTCs and MSI were assessed in the blood and representative tumor tissues of 100 CRC patients by flow cytometry (FCM) and PCR amplification. The data were correlated to relevant clinicopathological features of the patients, progression-free survival (PFS) and overall survival (OS) rates. RESULTS: MSI-high was detected in 44 (44.0%) patients, MSI-low in 37 (37%), and microsatellite stable (MSS) in 19 (19.0%) patients (P=0.007). The baseline CTCs count (<4 cells/7mL blood) was reported in 39% of the patients, and CTCs ≥4 cells/7mL blood in 61% of the patients (P=0.028). Improved PFS and OS rates were associated significantly with MSI-high (P<0.001), decreased CTC levels during the course of treatment (P<0.001) and post-treatment CTCs (P=0.008). There was no significant association between MSI-high and PFS or OS in early-stage patients (P=0.187 and P=0.187; respectively); however, it was associated significantly with better PFS and OS in late-stage patients (P<0.001). Multivariate analysis showed that only a change in serial CTC levels is considered an independent prognostic factor for OS (P<0.012). Post-treatment CTCs level, serial CTCs level changes during the course of treatment, lymph nodes and distant metastasis were independent prognostic factors for PFS (P<0.001, P= 0.047, P=0.001 and P<0.001; respectively). CONCLUSION: MSI and CTCs could be used as accurate, reliable and sensitive diagnostic and prognostic biomarkers for CRC patients' survival rates and outcomes.

Metastatic Breast Lobular Carcinoma to Unusual Sites: A Report of Three Cases and Review of Literature.

Invasive lobular carcinoma of the breast is the second most common type of invasive breast carcinoma. Invasive lobular carcinoma has an unusual pattern of metastases, which poses a diagnostic challenge for both clinicians and pathologists. We herein present three cases of breast invasive lobular carcinoma presented with metastasis to unusual sites, namely, uterus, colon and stomach. We recommend a higher index of suspicion in any case with breast cancer developing gastrointestinal tract or genital tract symptoms.