Oestrogen and progesterone receptor status of individual foci in multifocal invasive ductal breast cancer.

Widespread acceptance of breast conserving surgery for early breast cancer has led to renewed interest in multifocality, which is seen in 13-63% of breast cancers. According to current guidelines, oestrogen/progesterone receptor status is assessed on the sample obtained at initial core biopsy or the main tumour focus in multifocal breast cancer (more than one distinct tumour focus in a quadrant). We assessed receptor status of individual foci in multifocal breast cancer. Mastectomy specimens for 18 cases of multifocal breast cancer were identified. Immunohistochemical staining for oestrogen and progesterone receptors was performed on all tumour foci. On histological examination 11 patients demonstrated two independent tumour foci, three demonstrated three foci and four demonstrated four foci. Minor differences in oestrogen receptor score were seen between foci (attributed to the subjective nature of the scoring system), which did not affect the overall positive/negative classification. Sixteen patients (88%) were oestrogen receptor-positive. Progesterone receptor staining showed more variability between foci in two patients but, since the tumours were oestrogen receptor-positive this would not have affected clinical decision-making. No major differences in oestrogen receptor status between multiple tumour foci in the same quadrant were found in this pilot study.

Direct polymerase chain reaction amplification of formalin-fixed, paraffin-wax-embedded tissue after automated sequential laser microdissection and pressure catapulting.

A robust method to facilitate rapid laser microdissection and pressure catapulting (LMPC) coupled with direct polymerase chain reaction (dPCR) to eliminate the need for extraction of DNA before a PCR-based assay is described. This sequential LMPC-dPCR method is rapid and decreases the number of processing steps, reducing the chance of tissue loss and contamination.

Cyclooxygenase-2 expression predicts survival in malignant pleural mesothelioma.

The expression of cyclooxygenase 2 (COX-2) protein is increased in many tumours and may be associated with a more aggressive phenotype. We aimed to assess COX-2 expression in a large series of archival mesothelioma specimens. Archival tissue was obtained from 86 malignant pleural mesothelioma samples (histological subtype: 42 epithelial, 28 biphasic and 16 sarcomatoid). Overexpression of COX-2 was detected by immunohistochemical analysis. Positive staining was located in the cytoplasm of malignant tumour cells. Overall 51/86 (59%) tumour sections demonstrated COX-2 overexpression. The frequency varied with histological subtype with 31/42 (73%) of epithelial sections, 14/28 (50%) of biphasic sections and 6/16 (37%) of sarcomatoid sections recorded as positive. Kaplan Meier survival analysis indicated that overexpression of COX-2 was significantly related to improved prognosis (P < 0.001) and was an independent prognostic factor in multivariant analysis. Overexpression of COX-2 protein may confer a survival advantage in mesothelioma patients.