CD8+ lymphocytes and apoptosis in typical and atypical medullary carcinomas of the breast.

Medullary breast carcinoma (MBC) is a form of ductal invasive carcinoma (DIC) characterized by an abundant infiltration of the tumour by lymphocytes. MBC has been classified histologically into typical medullary carcinoma (TMC) and atypical medullary carcinoma (AMC), with TMC having a better prognosis than AMC and other DIC. The distribution of CD8+ lymphocytes within tumour nests and lymphocyte tracts, and apoptosis in lymphocytes and tumour cells within tumour nests, were studied in archived formalin fixed and paraffin embedded tissues of TMC and AMC. CD8+ lymphocytes tend to accumulate along the margins of lymphocyte tracts that adjoin tumour nests. There were significantly more CD8+ lymphocytes within tumour nests of TMC than AMC. TMC also tended to have more CD8+ lymphocytes within lymphocyte tracts than AMC. Apoptosis of lymphocytes in contact with tumour cells and of tumour cells in contact with lymphocytes was observed in both AMC and TMC within tumour nests but differences in the proportions of apoptotic tumour cells and lymphocytes between the two tumour types could not be established. The findings are consistent with CD8+ cytotoxic lymphocyte-mediated immunity contributing to the more favourable prognosis for TMC compared to AMC.

Cervical cancer in Brunei Darussalam.

INTRODUCTION: Cervical cancer caused by the human papilloma virus (HPV) is a common cancer in women. There is no published data on the recent incidence of cervical dysplasia, cervical cancer and genital warts caused by the different types of HPVs in Brunei Darussalam. METHODS: A cross-sectional, retrospective study was conducted utilising data from patients diagnosed with cervical cancer during the period 2005-2009 in Brunei Darussalam. The varying incidences of different types of cervical lesions among various ethnic and age groups, and in the overall population, were determined. RESULTS: The mean age-standardised incidence of invasive cervical cancer during the five-year period was 24.9 per 100,000 women per year (95% confidence interval [CI] 21.7, 28.1). Age-specific invasive cervical cancer incidence peaked in the age group 45-59 years. Chinese females tended to have a higher incidence of invasive cervical cancer (28.2 per 100,000 women per year; 95% CI 17.8, 38.7) than Malay females (20.6 per 100,000 women per year; 95% CI 17.1, 24.2), while other ethnic groups in Brunei Darussalam had a significantly lower incidence (6.5 per 100,000 women per year; 95% CI 3.0, 10.0). CONCLUSION: The results suggest that Brunei Darussalam has a relatively higher incidence of cervical cancer compared to its neighbouring countries. The findings support the need for more comprehensive screening, public education programmes and vaccination against HPV in the country.

Possible significance of differences in proportions of cytotoxic T cells and B-lineage cells in the tumour-infiltrating lymphocytes of typical and atypical medullary carcinomas of the breast.

Medullary carcinoma (MC) of the breast is a high grade carcinoma that has a relatively favourable prognosis compared to atypical medullary carcinoma (AMC) and other more common breast carcinomas. In a retrospective study in Brunei Darussalam of all available biopsy samples, we compared the nature of the tumour-infiltrating lymphocytes (TILs) in MC and AMC in relation to recorded tumour characteristics. CD4, CD8, CD20, CD25, CD45RO, and CD56 and common tumour biomarkers were detected immunohistochemically. The 11 cases of MC had no nodal metastases and survived without relapse, suggesting good tumour control. In contrast, 7 cases of nodal metastases and 1 relapse were observed in 12 AMCs. Although not statistically significant, there was a tendency for a greater proportion of AMCs to express the Her2/neu oncogene. Higher proportions of CD45RO+ and CD8+ cells, and lower levels of CD20+ cells, were characteristic of TILs in MC compared to AMC. The ratio of CTL to B-lineage cells in TILs in both tumours considered together was inversely related to the expression of HER2/neu and the presence of nodal metastases. The findings suggest that CTLs, rather than antibodies, may give better tumour control in MC relative to AMC. We propose that a comparison of the cellular, molecular and immunological characteristics of MC and AMC, as a paired model system, in a multi-centre investigation with a much larger number of samples will be valuable for better understanding mechanisms of tumour immunity.