Detection and characterization of circulating tumor cells in blood of primary breast cancer patients by RT-PCR and comparison to status of bone marrow disseminated cells

Introduction  

The role of circulating tumor cells (CTCs) in blood of primary breast cancer patients is still under investigation. We evaluated the incidence of CTCs in blood, we evaluated the correlation between CTCs and disseminated tumor cells (DTCs) in the bone marrow (BM), and we characterized CTCs for the expression of HER2, the estrogen receptor (ER) and the progesterone receptor (PR).     

Quantitative parameters to compare image quality of non-invasive coronary angiography with 16-slice, 64-slice and dual-source computed tomography

Multi-slice computed tomography (MSCT) is a non-invasive modality to visualize coronary arteries with an overall good image quality. Improved spatial and temporal resolution of 64-slice and dual-source computed tomography (DSCT) scanners are supposed to have a positive impact on diagnostic accuracy and image quality. However, quantitative parameters to compare image quality of 16-slice, 64-slice MSCT and DSCT are missing. A total of 256 CT examinations were evaluated (Siemens, Sensation 16: n = 90; Siemens Sensation 64: n = 91; Siemens Definition: n = 75). Mean Hounsfield units (HU) were measured in the cavum of the left ventricle (LV), the ascending aorta (Ao), the left ventricular myocardium (My) and the proximal part of the left main (LM), the left anterior descending artery (LAD), the right coronary artery (RCA) and the circumflex artery (CX). Moreover, the ratio of intraluminal attenuation (HU) to myocardial attenuation was assessed for all coronary arteries. Clinical data [body mass index (BMI), gender, heart rate] were accessible for all patients. Mean attenuation (CA) of the coronary arteries was significantly higher for DSCT in comparison to 64- and 16-slice MSCT within the RCA [347 ± 13 vs. 254 ± 14 (64-MSCT) vs. 233 ± 11 (16-MSCT) HU], LM (362 ± 11/275 ± 12/262 ± 9), LAD (332 ± 17/248 ± 19/219 ± 14) and LCX (310 ± 12/210 ± 13/221 ± 10, all p < 0.05), whereas there was no significant difference between DSCT and 64-MSCT for the LV, the Ao and My. Heart rate had a significant impact on CA ratio in 16-slice and 64-slice CT only (p < 0.05). BMI had no impact on the CA ratio in DSCT only (p < 0.001). Improved spatial and temporal resolution of dual-source CT is associated with better opacification of the coronary arteries and a better contrast with the myocardium, which is independent of heart rate. In comparison to MSCT, opacification of the coronary arteries at DSCT is not affected by BMI. The main advantage of DSCT lies with the heart rate independency, which might have a positive impact on the diagnostic accuracy. Christof Burgstahler and Anja Reimann contributed equally to this work     

Evaluation of a RT-PCR based routine screening tool for the detection of disseminated epithelial cells in the bone marrow of breast cancer patients

Purpose Numerous studies have shown that the presence of clinically occult disseminated tumor cells (DTC’s) in the bone marrow (BM) of breast cancer patients is associated with an unfavourable clinical outcome. Immunocytochemistry (ICC) remains the gold standard for their detection. While assays based on RT-PCR are available, they have not been used for routine detection of DTC’s. Methods To assess the quality of the assay, we performed a direct comparison of DTC detection rates in a large cohort of 385 patients using both standardized ICC and real-time RT-PCR protocols. Correlation rates were assessed, and results were compared with clinical data. Results A significant correlation between ICC and RT-PCR was observed (P < 0.01). Positivity rates were similar (both 35%) and the results of both methods agreed in 73% of cases (280/385). Conclusions We describe a real-time RT-PCR based protocol for DTC-detection that has been specifically designed for routine clinical laboratory use. As such, RT-PCR has the potential to become an alternative testing method for BM evaluation in breast cancer patients.     

Single nucleotide polymorphisms and haplotypes in the gene for vascular endothelial growth factor and risk of prostate cancer

Vascular endothelial growth factor (VEGF) plays a key role in the regulation of angiogenesis and has been related to cancer development and progression. To evaluate the role of VEGF single nucleotide polymorphisms (SNPs) and haplotypes in prostate cancer, we performed a case–control study including 702 prostate cancer patients and 702 male age-matched healthy control subjects. Seven VEGF candidate polymorphisms were determined by 5′-nuclease (TaqMan) assays. Furthermore, VEGF plasma levels and genotypes were analysed in a group of 64 healthy men. Haplotype analysis showed two separate blocks of high-linkage disequilibrium, formed by five polymorphisms upstream of the coding sequence (promoter and 5′-untranslated region) and two polymorphisms downstream of the coding sequence. None of the single polymorphisms or haplotypes was significantly associated with the presence of prostate cancer. In a multivariate regression analysis including age, VEGF genotypes and haplotypes as covariates and VEGF plasma level as dependent variable, none of the VEGF polymorphism or haplotypes was a significant predictor of VEGF plasma levels. The present data suggest that polymorphisms or haplotypes in the VEGF gene do not modify the risk of prostate cancer.     

SLNB and the importance of micrometastases in vulvar squamous cell carcinoma

With the exception of patients with tumors smaller than 2cm and infiltration less than 1mm, standard treatment for squamous cell carcinomas of the vulva includes ipsi- or bilateral inguinofemoral lymph node dissection. However, with only 20% of early stage patients presenting with lymph node metastases in the groin, the majority of these patients do not gain from the procedure, but are at risk of its complications and detriments. The sentinel lymph node biopsy (SLNB) method targets the lymph nodes most likely to contain metastasis and has proven high accuracy in predicting the absence of metastasis in non-sentinel lymph nodes when found negative on pathologic examination. The SLNB further provides for a more thorough examination of the harvested lymph nodes and hence increases the detection of micrometastases. Although the clinical significance of micrometastases is controversial, reports on patients with micrometastasis suffering recurrence emerge, making the importance of detecting micrometastases in the pathologic examination of the sentinel lymph nodes evident. Appreciating its limitations, the sentinel lymph node procedure shows evidence of evolving into a feasible and safe procedure in the hands of experienced surgeons, pathologists and nuclear medicine physicians in early stage vulvar carcinoma patients. Still, larger multicenter trials are needed to assess its accuracy and safety.