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Biomedical subjects

B Delahunt

Publications and source records attributed to B Delahunt.

At least 55 records · Page 3Linked to original sources

Proliferation of renal cell carcinoma assessed by fixation-resistant polyclonal Ki-67 antibody labeling. Correlation with clinical outcome.

BACKGROUND: Although tumor staging is an important prognostic parameter for renal cell carcinoma (RCC), postnephrectomy survival interval is often difficult to predict for individual patients. This is the result of varied growth characteristics, which in tumors of similar stage govern both time to recurrence and rate of tumor dissemination. Polyclonal Ki-67 antibody labels a proliferation-specific antigen expressed in actively proliferating cells and is applicable to formalin fixed paraffin embedded archival tissue. This study was designed to test the prognostic utility of Ki-67 antigen labeling in a series of RCC and to compare the data with those derived from other markers of cell proliferation. METHODS: Polyclonal Ki-67 antibody staining of 206 cases of RCC was undertaken using the streptavidin-biotin method. Cases were grouped according to Ki-67 indices and Kaplan-Meier survival curves were constructed. Groups were compared in terms of survival for all cases and for each of Robson's stages using the log rank test. Further sections were stained for proliferating cell nuclear antigen (PCNA) and silver-staining nucleolar organizer regions (AgNORs). The prognostic significance of Ki-67 antigen, PCNA and AgNOR staining, histologic grade, and tumor stage were compared using Cox's proportional hazard model. RESULTS: Ki-67 immunostaining was achieved for 173 cases with indices ranging from 0.1% to 30.4%. Division of tumors with indices 6% or less and greater than 6% showed a significant difference in survival between groups for all cases and for each Robson stage. Ki-67 and PCNA indices, AgNOR scores, and tumor dissemination (Robson Stage 3 and 4) retained a significant association with survival on multivariate analysis. CONCLUSIONS: Polyclonal Ki-67 antibody immunostaining provides significant survival information that complements that derived by other markers of cell proliferation and tumor staging.

Biomarkers, Tumor↗

Proliferation kinetics of streptozotocin-induced renal tumours in mice.

Renal tumours were induced in female mice 132 days after intravenous administration of streptozotocin. The tumours exhibited papillary and/or solid architecture with papillary tumours showing no histological evidence of malignancy. Malignant behaviour, manifest as infiltration of adjacent renal tissue and lymphatic infiltration, was noted for tumours with solid architecture. Intermediate architectural forms exhibiting dual papillary and solid architecture were identified. Proliferation kinetics were evaluated by enumeration of silver-staining nucleolar organizer regions and proliferating cell nuclear antigen expression. The results showed a stepwise progress in cell proliferation between histologically normal renal tubule epithelium [untreated animals, mean AgNOR score (MAS) 2.32, mean PCNA index (MPI) 0.53%; treated animals, MAS, 2.44; MPI 0.99%], dysplastic tubule epithelium (MAS, 4.15; MPI 1.65%), papillary tumours (MAS, 5.90; MPI 3.89%) and solid tumours (MAS, 6.94; MPI, 6.80%). Solid tumours as a group were significantly larger than papillary tumours and were associated with a significantly longer mean post-injection survival interval. The findings suggest that at least some solid tumours evolve from tumours exhibiting papillary architecture.

Adenoma↗

Phlyctainophora lamnae (Nematoda; Philometridae) from dogfish Squalus acanthias off southern New Zealand.

Coiled globose female nematodes and larvae, identified as Phlyctainophora lamnae Steiner, 1921, were found in tumour-like lesions on the tail fin of spiny dogfish Squalus acanthias L. (Squalidae) caught off southern New Zealand. Nematodes provoke a chronic inflammatory response by the host. No male nematodes were recovered. This is the first record of the genus from New Zealand and the first record of adult Phlyctainophora from the Southern Hemisphere. Phlyctainophora squali Mudrey & Dailey, 1969 is considered a synonym of P. lamnae.

Animals↗

Tumors of pineal parenchymal cells: a correlation of histological features, including nucleolar organizer regions, with survival in 35 cases.

We studied 35 parenchymal neoplasms arising in the pineal gland, including 11 pineoblastomas, 21 pineocytomas, and three mixed pineocytoma-pineoblastomas. Pineoblastomas were most commonly found in children (mean age, 12.6 years). The median postsurgical length of survival for seven patients, including five with remote metastases, with fatal outcome was 24 months. The 21 pineocytomas were found in older individuals (mean age, 26.8 years). Four patients with pineocytoma died; two before surgery and two in the immediate postoperative period. The remaining 17 patients survived for intervals between 6 and 118 months after surgery. Two mixed pineocytoma-pineoblastomas were found in infants who died a few months after biopsy, whereas a third patient, an adult, was alive at 46 months after excision and irradiation. Both pineoblastoma and pineocytoma exhibited variable immunoreactivity to neurofilament proteins, synaptophysin, glial fibrillary acidic protein, S-100 protein, retinal-S antigen, and rhodopsin; the highest percentages of positive cells stained with synaptophysin. Three pineocytomas exhibited ganglionic differentiation and two of them also showed a glial component. Prognosis could not be correlated with the degree of divergent differentiation. Comparison of silver-stained nucleolar organizer region (AgNOR) counts between pineoblastomas and pineocytomas suggests that the former are more actively proliferative than the latter, with mixed pineocytoma-pineoblastoma showing intermediate activity. There was no correlation between AgNOR score and prognosis within the three tumor groups.

Adolescent↗

Analysis of the prevalence of voiding symptoms in Maori, Pacific Island, and Caucasian New Zealand men.

OBJECTIVES: Data from a community-based sample of 515 men were used to assess the prevalence and presentation of voiding symptoms in Caucasian, Maori, and Pacific Island men in the city of Porirua, New Zealand. METHODS: A random sample, stratified by age groups of 10 years, was obtained for men 40 years and older. Two hundred men were entered into each 10-year age stratum. Frequency of symptoms and quality of life were measured using the International Prostate Symptom Score (IPSS) questionnaire. Bothersomeness of symptoms was assessed using questions from the American Urological Association symptom bother index. Data were analyzed according to age and ethnic group with differences between groups measured by analysis of variance. RESULTS: Symptom score was found to increase with increasing age of subjects, with men in the 40 to 49 years age group recording a mean score (+/- SE) of 2.9 +/- 0.3, increasing to a mean score of 4.8 +/- 0.4 for men aged 50 to 59 years, 7.4 +/- 0.9 for men aged 60 to 69 years, and 7.4 +/- 0.9 for men in the 70 year and older age group. Significant symptoms, represented by a symptom score of 8 or greater, were found in 12.9% of men aged 40 to 49 years, 22.3% of men aged 50 to 59 years, 33.7% of men aged 60 to 69 years, and 33.3% in the 70 year and older age group. No difference was demonstrated in the prevalence of symptoms between Caucasian, Maori, and Pacific Island men. CONCLUSIONS: Despite having a similar prevalence of voiding symptoms to Caucasian men, few Maori or Pacific Island men seek help for their urinary symptoms. The level of understanding of the underlying disease process is poor for men of all ethnic backgrounds and emphasizes the important need for greater public awareness and education with respect to prostate disease.

Adult↗

Comparison of silver-staining nucleolar organizer region (AgNOR) counts and proliferating cell nuclear antigen (PCNA) expression in reactive mesothelial hyperplasia and malignant mesothelioma.

Previous workers have used counts of colloidal silver-stained nucleolar organizer regions (AgNORs) to help distinguish reactive from malignant mesothelial processes. We sought to compare the demanding technique of AgNOR counting with the identification of proliferating cell nuclear antigen (PCNA) in 10 pleural malignant mesotheliomas and 11 reactive mesothelial proliferations. The mean AgNOR count was significantly higher in malignant compared to reactive lesions (5.10 [95% confidence interval, CI 4.35-5.84] vs 3.68 [95% CI 3.17-4.19], p = 0.004), as was the PCNA index (26.9 [95% CI 17.37-36.49] vs 9.67 [95% CI 4.94-14.39], p = 0.004). Less overlap was seen with PCNA indices and no reactive mesothelial proliferations had a PCNA index greater than 20%, suggesting that scores over this level may be a specific indicator of malignancy in this setting. There was only a weak correlation between the 2 proliferation indices suggesting that PCNA and AgNORs are present at somewhat different times of the cell cycle and/or persist in the post-S phase cell for variable lengths of time.

Adult↗

The effect of finasteride on prostate volume, urinary flow rate and symptom score in men with benign prostatic hyperplasia.

This study was designed to determine the efficacy of the 5 alpha-reductase inhibitor finasteride (Proscar, MK-906) in men with reduced urinary flow rates and symptoms of urinary outflow obstruction secondary to benign prostatic hyperplasia. Forty-five men were randomized to one of three groups receiving either placebo, 1 mg/day or 5 mg/day finasteride for the first 12 months of the study period. At the end of this period all men received 5 mg/day finasteride for a further 2 years. Efficacy was determined by measurement of prostate volume, maximum urinary flow rate, and symptom score using a modified Boyarsky assessment. Prostate volume reduced by 20 and 27%, respectively, for those on 1 and 5 mg after the first year. At 3 years the volume had reduced by 43%. This reduction in prostate volume was associated with an improvement in maximum urinary flow rate by 50% (1 mg), and 35% (5 mg) at 1 year, and 36% at 3 years. The total, obstructive and non-obstructive symptom scores decreased (improved) for patients on 1 and 5 mg finasteride, with the total score reducing by 33% from baseline at year 3. The results demonstrate that finasteride causes a modest but significant clinical improvement in men with urinary outflow obstruction secondary to benign prostatic hyperplasia.

Aged↗

Occupational risk for renal cell carcinoma. A case-control study based on the New Zealand Cancer Registry.

OBJECTIVE: To evaluate occupational risk factors for renal cell carcinoma. SUBJECTS AND METHODS: A case control design was employed using data reported to the New Zealand Cancer Registry from 1978 to 1986 inclusive. The occupational risk for renal cell carcinoma was derived by comparison with the occupation of cases of non-urinary tract malignancy reported to the Registry over the same period. RESULTS: An active occupational code was derived for 86.2% of all cases and 98.9% (710) of male cases. In a series of case-control studies for selected occupational groups, adjusting for patient age and smoking history, a significantly increased relative risk for the development of renal cell carcinoma among firefighters (RR 4.89, 95% CI 2.47-8.93) and painters (RR 1.79, 95% CI 1.31-3.44) was demonstrated. CONCLUSION: The data suggest that both firefighters and painters may be at an increased risk of developing renal cell carcinoma, which is likely to be of significance as both occupational groups are frequently exposed to known carcinogens.

Adult↗

Renal cell carcinoma in New Zealand: a national survival study.

OBJECTIVE: To determine clinical and pathologic prognostic factors for renal cell carcinoma (RCC) using cases reported to a population-based cancer registry. METHODS: All cases of RCC reported to the New Zealand Cancer Registry between 1976 and 1986 were retrieved and data analyzed to determine parameters of prognostic importance. RESULTS: In eleven years, 1,308 cases of RCC (66.7% males and 33.3% females) were reported to the New Zealand Cancer Registry. The age-standardized incidence rate was 3.78 per 10(5) person-years and showed no significant trend over the period of the study. There was a significant difference in the age at presentation between the largest racial groups (Maori 52.2 years; non-Maori 63.2 years), which is accounted for by increased predisposing risk factors among Maori. The five-year actuarial survival rate was 42.4 percent with 63 percent of patients reported dead in follow-up to December 1990. In the series, patient gender (female > male), tumor laterality (right > left), stage (intrarenal > localized > disseminated), grade (1 > 2 > 3 > 4), and treatment modality (surgery > nonsurgery) were found to be significant prognostic factors, although only tumor stage and treatment modality were of independent significance. Tumor laterality was of prognostic significance for Stage II (localized) surgically treated tumors only. CONCLUSIONS: The results of the study emphasize the paramount importance of tumor stage as a prognostic parameter for RCC. The prognostic significance of laterality for localized, surgically treated tumors suggests that radical nephrectomy is less likely to result in tumor clearance for left-sided RCC than for tumors on the right side.

Actuarial Analysis↗

Computerized nuclear morphometry and survival in renal cell carcinoma: comparison with other prognostic indicators.

Morphometric nuclear parameters were compared with patient survival for a series of 174 renal cell carcinomas (RCC) collected over a 30 yr period. Stepdown regression showed long diameter, average feret diameter, form factor and the ratio of average feret diameter to equivalent diameter to be significantly associated with survival. Nuclear area, nuclear perimeter, equivalent diameter, ratio of long diameter to average feret diameter and coefficients of variation of nuclear area and nuclear perimeter were not significantly correlated with survival. All parameters were correlated with a 3 division nuclear grading classification using analysis of variance. Multivariate analysis showed nuclear form factor, tumor stage, silver staining nucleolar organizer region numbers and proliferating cell nuclear antigen expression to be independently associated with survival. The results of this study indicate that form factor is the most discriminate morphometric parameter for RCC, providing survival data additional to that derived from tumor staging and from markers of tumor proliferation.

Carcinoma, Renal Cell↗

Awareness of testicular cancer in New Zealand men.

Testicular cancer is the most common malignancy in young men and is frequently associated with delays in presentation. It has been postulated that ignorance and poor awareness of this type of cancer may contribute to such delays, which may result in high stage disease and subsequent treatment-related morbidity. This study was undertaken to assess the level of awareness of testicular cancer in a sample of 500 men from Wellington, New Zealand, and to specifically examine awareness related to the age, race, and socio-economic level of the respondents. Sixty-one per cent of men returned a satisfactorily completed questionnaire. Most (70%) were unaware that cancer of the testis could develop. Of those who correctly identified testis cancer as occurring, half recognized the most commonly affected age group, 40% understood testis cancer could be treated, and 14% believed testis cancer could be cured with treatment. The lowest awareness score (mean +/- s.d.) were found in the 18-30 age group. The score in this group (2.82 +/- 1.47) was significantly lower than that seen in the 31-40 (mean 3.66 +/- 1.81, P = 0.009) or 41-50 (mean 3.57 +/- 2.16, P = 0.036) age groups. Differences were also seen between ethnic groups, with Maori having significantly lower scores than non-Maori (Maori, mean 2.69 +/- 1.52; non-Maori, 3.45 +/- 1.83; P = 0.044). Higher scores were associated with higher socio-economic grouping. The overall poor awareness of men in this study supports the need for a public education programme aimed at encouraging men to seek early advice following the recognition of testicular masses.

Adolescent↗

Assessment of proliferative activity in Wilms' tumour.

The proliferative activity in 26 cases of Wilms' tumour was studied by enumeration of silver-staining nucleolar organizer regions (AgNORs) and proliferating cell nuclear antigen (PCNA) staining of the blastemal, epithelial and stromal components of the tumours. The PCNA and AgNOR scores derived from the blastemal (PCNA range 18.9-81.4%, AgNOR range 2.11-4.95) and epithelial (PCNA range 24.1-74.2%, AgNOR range 2.47-4.41) components of the tumours were significantly higher than those of the stromal component (PCNA range 3.4-64.7%, AgNOR range 2.20-4.26). Ten of the patients had died with recurrent or metastatic tumour (mean survival 29 months) while the remaining 16 were disease free (mean follow-up 95 months) at the time of the study. The prognostic significance of PCNA and AgNOR for Wilms' tumour was evaluated by dividing the tumours into groups exhibiting low (PCNA < or = 40 or AgNOR < or = 4) or high (PCNA > 40 or AgNOR > 4) proliferative activity. There was a significant difference in the survival of the two groups for tumours treated with preoperative chemotherapy (PCNA, P = 0.049; AgNOR, P = 0.02), while no significant difference was observed from tumours resected prior to the administration of chemotherapy. The results of this study suggest that assessment of proliferation activity in postchemotherapy Wilm's tumours may be a useful indicator of prognosis.

Cell Division↗

Familial cystic nephroma and pleuropulmonary blastoma.

BACKGROUND: Cystic nephroma (CN) and pleuropulmonary blastoma (PPB) are rare tumors without any previously recognized familial association. METHODS: Two cases of CN and one case of PPB in three siblings are reported. RESULTS: A 27-month-old girl and a 31-month-old boy underwent nephrectomy for CN and are free of disease in the contralateral kidney 16 and 14 years later, respectively. Their 28-month-old sister underwent pleuropneumonectomy with postoperative chemotherapy for PPB and died of recurrent disease 9 months later. CONCLUSION: To the knowledge of the authors, these cases represent the first reported familial occurrence of CN and the second of CN and PPB among siblings. The inheritance of a germline mutation predisposing to the development of these tumors is postulated.

Child, Preschool↗

Proliferating cell nuclear antigen (PCNA) expression as a prognostic indicator for renal cell carcinoma: comparison with tumour grade, mitotic index, and silver-staining nucleolar organizer region numbers.

Proliferating cell nuclear antigen (PCNA) expression in renal cell carcinoma (RCC) was determined by immunohistochemical staining using the PC10 clone. PCNA indices ranged from 2.4 to 53.1 per cent with mean indices of 12.6, 19.0, and 31.6 per cent for grades 1 to 3 RCC and 31.9 per cent for sarcomatoid RCC. There was a significant difference between the indices of grades 1 and 3 and grades 2 and 3 tumours and between grades 1 and 2 RCC and sarcomatoid RCC. AgNOR scores and mitotic indices were determined for each tumour and comparison of PCNA indices with mean AgNOR scores and mitotic indices showed only a weak correlation (PCNA/AgNOR r = 0.406, PCNA/mitotic index r = 0.315). Tumours were divided according to PCNA index (< or = 18 per cent and > 18 per cent) and there was a significant difference in survival between the two groups, for all cases, and for each of the Robson stages. Multivariate analysis using Cox's proportional hazard model showed PCNA index, tumour stage, and mean AgNOR score to be independent predictors of survival, while tumour grade and mitotic index were found to be dependent variables.

Antigens, Neoplasm↗

The evolution and development of the urinary catheter.

The urinary catheter is one of the most frequently used medical devices and has a long and intriguing history of development. This paper describes the catheter from its simple beginnings through the subtle but important changes it has undergone paralleling the advances in plastics technology witnessed this century. The changes have not been without controversy and the recent association of catheters with tissue toxicity, which has forced the implementation of strict guidelines for their manufacture and use, is described.

Catheters, Indwelling↗