Anti-PSA immunoreactivity in primary prostatic tissues from black African men.

Prostatic specific antigen (PSA) immunoreactivity is the most commonly used histological marker to identify epithelial cells of prostate origin. Unlike tissues from white men in which grade-related variability has been reported, the pattern of PSA immunoreactivity in prostatic tissues from black African men is presently unknown. This study was done to evaluate the pattern of PSA staining in sections of normal, benign hyperplastic and malignant prostatic glands from men from this sub-population. PSA immunostaining was done on 4-microm serial sections from archival specimens of benign prostatic hyperplasia (BPH) and carcinoma of the prostate (CaP) obtained from black African men using standard immunoperoxidase techniques. The intensity of PSA immunoreactivity of the glands was scored using a semi-quantitative method. PSA expression decreased with increasing de-differentiation of the tissue histotype with poorly differentiated tumours staining least. PSA immunoreactivity was strong in 100% of normal glands and 84% of BPH glands and moderate in the rest. In contrast, PSA immunopositivity was strong in 32% of CaP glands, moderate in 26%, weak in 34% and absent in 8%. Statistical comparison revealed that PSA expression was significantly higher in benign tissues (normal/ atrophic and BPH) than in CaP glands [p = < 0.0001]. Our findings show that PSA immunoreactivity is grade-related in prostatic tissues from black men and this has implications for clinical diagnosis and research. It also confirms the limitations of PSA-testing in diagnosing CaP, and indicates that newer immunohistochemical tests for malignant prostatic cells should be acquired by Sub-Saharan laboratories.

Further characterization of storage-related alterations in immunoreactivity of archival tissue sections and its implications for collaborative multicenter immunohistochemical studies.

Storage of unstained paraffin slides may lead to the deterioration of specimens and failure to detect cellular proteins immunohistochemically. Although the implication of age-induced alterations on multicenter immunohistochemical studies would be considerable, they have not been investigated previously. The current study was undertaken to examine the effect of this factor further and to explore new ways of overcoming the resultant shortcomings. The authors now report on the immunodetection of a host of antigens in similarly preserved unstained serial paraffin slides obtained from three centers using a panel of eight antibodies. Staining of recently prepared sections from the authors' centers resulted in similar strong patterns in seven of eight antibodies, with one antibody demonstrating variable immunoreactivity. However, storage of unstained paraffin sections at room temperature resulted in a variable but progressive decrease in expression of several tissue antigens. Although the loss in antigenicity was proportional to the length of storage, the effect was reversible if super antibody concentrations were used. The authors conclude that recently prepared paraffin sections from centers with similar fixation protocols have similar immunoreactivity and are suitable for use in comparative multicenter studies. However, in view of the delays that may attend tissue transportation during these projects, the authors suggest that test systems should be checked for age-induced antigen degradation by incubating sections with higher antibody concentrations.

Bacillary angiomatosis in an HIV positive child. First case report in Zimbabwe.

Bacillary angiomatosis is a recently recognised condition that is seen mainly in adult patients with the acquired immunodeficiency syndrome (AIDS). Its importance lies in the fact that it can be confused with Kaposi's sarcoma which is now the commonest malignant condition in male adult patients in this country. Unlike Kaposi's sarcoma however, it is curable. Ours is the first reported case of bacillary angiomatosis in Zimbabwe.

Fine needle aspiration cytology in the diagnosis of hepatocellular carcinoma.

Fine needle aspiration (FNA) of the liver without ultrasound guidance was performed on 110 patients with hepatocellular carcinoma (HCC). The median age was 52 years, with a range of 16 to 86 years. There were 90 males and 20 females (a male: female ratio of 4.5:1), with a median age of 51.5 years (range 16 to 86 years) and 55.5 years (range 17 to 72 years) respectively. FNA was reported as showing malignancy in 92 (84 pc, 95 pc CI 77 to 91 pc) patients; 80 (73 pc) were definite HCC, 12 (11 pc) were malignant unspecified, seven (6 pc) were suspicious of malignancy, seven (6 pc) had no malignant cells and four (4 pc) were non-diagnostic. The only complication observed was dizziness in one patient. We conclude that FNA of the liver for the diagnosis of HCC is a safe, simple and accurate procedure which can be undertaken in settings that would otherwise not be suitable for formal liver biopsy.

Bone marrow involvement in non-Hodgkin's lymphoma in Zimbabwe.

Lymph node and bone marrow trephine biopsies of seventy two consecutive cases of non-Hodgkin's lymphoma occurring among black Zimbabweans were reviewed to determine bone marrow involvement. The bone marrow was involved in 23.6% of patients but the proportion of bone marrow positive cases was highest in low grade lymphomas, though these were the least common type of lymphoma encountered. Cells infiltrating the marrow showed high degree of concordance with corresponding lymph node histology. Low grade lymphomas (CLL excluded) had a predominantly diffuse pattern of marrow involvement while intermediate and high grade lymphomas had nearly equal proportions with diffuse and focal patterns. Bone-marrow involvement did not make a significant difference to the staging of non-Hodgkin's lymphoma as most cases not involving the marrow also presented with advanced disease. Mean age of patients was negatively correlated with histological grade but was not related to bone marrow involvement. Central nervous system involvement occurred mostly in the high grade lymphomas and was proportionately distributed between bone marrow positive and negative cases. 40% of non-Hodgkin's lymphoma were associated with HIV infection but HIV-associated lymphoma surprisingly very rarely infiltrated the bone marrow.

Virilization due to ovarian hyperthecosis in a postmenopausal woman.

A 51-year-old woman presented with hirsutism and virilization of gradual onset. The serum gonadotropin concentrations were in the postmenopausal range, the serum testosterone concentration was markedly elevated (9.8 nmol/l) and the serum estradiol concentration (220 pmol/l) was elevated above the postmenopausal range. A selective venous catheterization study demonstrated raised serum testosterone and androstenedione levels in ovarian veins and suggested the presence of a left ovarian tumor. The raised peripheral estradiol level was shown to be due to ovarian hypersecretion. After bilateral oophorectomy the serum testosterone became normal. Ovarian histology revealed bilateral stromal hyperthecosis. Ovarian hyperthecosis is a rare but important cause of serum testosterone levels in the neoplastic range. This is the third case reported of postmenopausal virilization due to ovarian hyperthecosis and the first report of a selective venous catheterization study in such a patient.