Human mammaglobin transcript amplification for differential diagnosis in a breast cancer metastatic to dura mater.

BACKGROUND: In breast cancer (BC), metastases to the central nervous system usually arise in women with advanced disease. Diagnosis of leptomeningeal (LM) metastasis is based on neurological symptoms, imaging studies and cytological detection of malignant cells in the cerebrospinal fluid (CSF). However, often these approaches are not sensitive enough to recognize leptomeninges involvement and subsequently to make a diagnosis of LM carcinomatosis. This study investigated the employment of reverse transcriptase-polymerase chain reaction (RT-PCR) for the human mammaglobin (hMAM) gene in a case of BC with cerebral metastases in which the involvement of the leptomeninges was in doubt. MATERIALS AND METHODS: Amplification of hMAM mRNA was performed from CSF cells by RT-PCR. RESULTS: No amplification of hMAM was obtained from the CSF cells. CONCLUSION: RT-PCR for human mammaglobin mRNA of the CSF in BC patients with brain metastases may aid clinical determination of LM involvement and consequently the choice of the most effective therapy regimens for affected patients.

Detection of circulating tumour cells in breast cancer patients using human mammaglobin RT-PCR: association with clinical prognostic factors.

BACKGROUND: So far discordant results regarding the significance of tumour cells circulating in peripheral blood (CTCs) of breast cancer (BC) patients have been reported. Our aim was to evaluate the association of indirect CTC detection by amplification of human mammaglobin (hMAM) gene expression with traditional prognostic markers of clinical outcome in BC at the time of diagnosis. PATIENTS AND METHODS: Peripheral blood samples from 190 patients with invasive and 12 patients with in situ BC, before therapy and/or surgery, from 184 patients with benign breast disease and from 146 healthy volunteers were tested for hMAM expression by a nested reverse transcriptase-polymerase chain reaction (RT-PCR) assay. Correlations between CTCs and age at diagnosis, tumour type and size, grading, lymph node involvement, oestrogen and progesterone receptor status, HER-2/neu expression and Ki-67/MIB-1 labelling index were assessed through the odds ratio (OR) point estimates, considering OR >2.0 or <0.5 as being clinically relevant. ORs and their corresponding 95% confidence limits (95% CL) were obtained by logistic regression analysis. RESULTS: Expression of hMAM was found only in peripheral blood of patients with invasive BC (9.5%) and multivariate logistic regression analysis indicated its association with lymph node involvement (pN1-pN3 vs. pN0, OR=5.6, 95% CL=1.4-22.6; p=0.009), tumour size (pT2-pT4 vs. pT1, OR=2.3, 95% CL=0.6-9.0; p=0.207) and negative ER status (OR=2.5, 95% CL=0.6-10.0; p=0.227). CONCLUSION: Our data show that CTC detection in invasive BC at the time of diagnosis is associated with poor prognosis and may also be used as an additional prognostic indicator.

Diagnosis and origin determination of malignant pleural effusions through the use of the breast cancer marker human mammaglobin.

As was reported that human mammaglobin (hMAM) may be expressed in malignant pleural effusions (PEs), we investigated the relevance of hMAM reverse-transcriptase polymerase chain reaction (RT-PCR) for their diagnosis and determination of primary origin. Two hundred and twenty-eight malignant (132 male, 96 female) and 185 benign (132 male, 53 female) PEs were investigated. Statistical analyses evaluated the diagnostic performance parameters in all PEs and in cytologically negative malignant PEs, the association between hMAM and benign or malignant status by the direct index of correlation [diagnostic odds ratio (DOR)], chi test, and P value (P). In addition, the discriminative diagnostic power of hMAM expression, independently in breast cancer, lung cancer (LC), malignant mesothelioma (MM), and other cancers was evaluated. In the entire patient population, hMAM was detected in 45.6% and 5.4% of malignant and benign PEs, respectively, in the male group in 41.7% and 4.5% and in the female group in 51.0% and 7.5% of malignant and benign PEs, respectively. A statistically significant correlation between hMAM and malignancy was found in the entire population (DOR=14.68, P<0.001) and in the male (DOR=15.00, P<0.001) or female (DOR=12.77, P<0.001) groups. hMAM RT-PCR increased the diagnostic rate of malignant PEs as it allowed us to detect as malignant 32.1% of cytologically negative PEs. In female patients the positivity of hMAM indicated with higher probability (50.8%) the origin of PEs from breast cancer but lower probability from LC (17%), MM (9.4%), or other cancers (15.1%), whereas in male patients it indicated with similar probability (about 40%) the origin from LC or MM. Our results suggest that hMAM RT-PCR may provide information both in the diagnosis of PE and in the search for the primary site of neoplasia, either in male or female patients.

Molecular detection of human mammaglobin in cerebrospinal fluid from breast cancer patient with leptomeningeal carcinomatosis.

Leptomeningeal (LM) carcinomatosis is an increasing clinical complication in patients with advanced breast cancer (BC). The LM carcinomatosis diagnostic procedures rely mainly on cerebrospinal fluid (CSF) cytology, although both the amount of CSF and the number of malignant cells remain limiting factors. Therefore, efforts should be made to design new highly sensitive diagnostic tools to detect malignant cells in CSF of BC patients with LM carcinomatosis. In this study, the human Mammaglobin (hMAM) mRNA amplification by RT-PCR was employed to detect metastatic cells in CSF and thus, to diagnose LM carcinomatosis in a BC patient. Our data demonstrate that hMAM transcripts are expressed in the CSF of a BC patient with LM carcinomatosis, hence making RT-PCR for hMAM a potentially suitable test to identify occult BC cells in the brain.

Assessment of RT-PCR detection of human mammaglobin for the diagnosis of breast cancer derived pleural effusions.

The present study investigates the diagnostic significance of human mammaglobin (hMAM) mRNA expression in pleural effusions (PE) from breast cancer (BC) patients. Two hundred and fifty PE samples, including 32 from patients who had diagnosis of BC, 116 from patients with other cancers, and 102 from patients with benign diseases, were subjected to nested reverse-transcription polymerase chain reaction (RT-PCR) for hMAM, and the results were compared with conventional cytology. hMAM was found expressed in 76/250 (30.4%) total PE and in 23/28 (sensitivity of 82.1%) of the PE subgroup owing to metastasis from BC. The specificity for hMAM detection method was 75.7%, whereas accuracy, positive predictive value, and negative predictive value were 76.4%, 30.3%, and 97.1%, respectively. hMAM was also detected in 46/116 (39.6%) PE specimens from other types of cancer and in 7/102 (6.8%) from benign diseases. Comparative analysis of RT-PCR and cytology showed that 14 PE samples from metastatic BC (50%) were positive by both PCR and cytology, 9 (32.1%) were positive only by PCR and 5 (17.9%) were negative by both tests, whereas no cases were found of positive cytology with negative PCR. RT-PCR increased sensitivity of BC effusion detection to 32.1% (McNemar test, P=0.004). We demonstrated that RT-PCR for hMAM test was more sensitive than cytomorphology suggesting that, although hMAM is not BC specific, it may be useful in adjunct to cytology for the routine screening of malignant BC effusions.