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I N Soomro

Publications and source records attributed to I N Soomro.

34 records · Page 2Linked to original sources

Morphological pattern and frequency of thyroid tumors.

OBJECTIVE: The present study was done to evaluate the frequency of thyroid cancer and to find out the prevalence of histological types of thyroid tumor with respect to age and sex group. SETTING: This study included consecutive cases of malignant tumors of thyroid gland, which were diagnosed in the Department of Pathology at the Aga Khan University Hospital, Karachi during the period of three years (1995-1997). METHODS: These cases were evaluated on H & E stained sections from paraffin embedded 10% buffered formalin fixed tissue blocks. Special stains and immunohistochemical analysis were performed whenever required. RESULTS: A total of 8541 malignant tumors were diagnosed in a period of 3 years which included 103 (1.2%) cases of thyroid cancer. Thyroid tumors were more prevalent in females with female to male ratio of 2.6:1. Papillary carcinoma (69%) was the most common histological type of thyroid tumors, followed by follicular carcinoma (11.6%), medullary carcinoma (9.7%), anaplastic carcinoma (5.9%), non-Hodgkin's lymphoma (2.9%) and unclassified tumors (0.9%) in order of frequency. CONCLUSION: Thyroid cancer was more common in females. Papillary carcinoma was the most common histological type of thyroid tumors in females as well as in males. Papillary carcinoma was more prevalent in third, fourth and fifth decades of life while follicular and anaplastic carcinomas were more frequent after the fourth decade of life.

Adult↗

p53 and PCNA expression in benign, atypical and malignant meningiomas.

OBJECTIVE: Alterations: p53 genes are turning out to be the most common genetic alterations in human cancers. Due to long half-life of mutated p53, its detection is possible by immunohistochemistry. Proliferating cell nuclear antigen (PCNA) is expressed by dividing cells, hence has been shown to correlate with prognosis. We have used monoclonal antibodies protein DO-7 (p53) and PC10 (PCNA) to see whether their expression correlates with histological grading in meningethelial tumour. MATERIAL AND METHODS: Twenty nine meningiomas (20 benign, 7 atypical and 2 malignant) were selected from the records of our laboratory. p53 and PCNA expression was sought by immunohistochemistry using Peroxidase Anti Peroxidase (PAP) technique. RESULTS: Four benign and 2 atypical meningiomas showed weak staining for p53. Both malignant meningiomas showed strong positivity for p53. Six benign meningiomas had less than 5% PCNA positivity, one 10% positivity and three showed 20% positivity. PCNA positivity ranged for 10-80% in atypical meningiomas. In two malignant meningiomas PCNA positivity was 70% and 90%. CONCLUSION: It is worthwhile to include p53 and PCNA expression along with histologic assessment in predicting outcome of meningiomas. A larger series with complete follow-up is essential in assessing value of these markers which unfortunately remains a dream in our country.

Humans↗

Spinal cord compression: histologic spectrum of lesions.

Histologic diagnosis ultimately determines the prognosis and treatment of lesions causing spinal cord compression. Modern imaging techniques have revolutionized the procedure of localizing lesions presenting with signs and symptoms of spinal cord compression. As a result, these lesions are more accessible for fine needle aspiration and biopsy. A quick diagnosis is possible if cytologic preparation is made. Similarly, intraoperative frozen section facility not only provides rapid diagnosis, but also offers opportunity of appropriate management decision there and then. Histology in many cases needs help of special stains and immunocytochemistry. This study looks at the histologic spectrum of these lesions, gender distribution and age range in Pakistani population.

Adenocarcinoma↗

Diagnostic evaluation of fine needle aspiration cytology in the management of palpable breast lesions.

A total of 113 fine needle aspirates of the breast masses were evaluated in which the subsequent biopsy or mastectomy specimen were also available for histological examination. The age ranged from 16 to 80 years with a mean of 42 years. In benign conditions the mean age was 34.7 years while in malignant cases it was 48 years. The cytological diagnoses were compared with the histological results which revealed that the specificity and sensitivity of fine needle aspiration cytology in the palpable breast lesions was 86.1% and 89.2% respectively with a positive predictive value of 93% and efficiency of 88.2%. Similar statistics from other series in which the cytological results of breast lesions were compared with histological results, revealed almost same results which suggest that fine needle aspiration cytology is an effective and accurate technique for the diagnosis and management of palpable breast lumps.

Adolescent↗

Predicting prognosis in lung cancer: use of proliferation marker, Ki67 monoclonal antibody.

An investigation was carried out to assess the prognostic significance of proliferation marker Ki67 in a group of lung cancer patients treated by surgery (limited disease). Tissue was not available for Ki67 immunostaining in inoperable group. The diagnosis is established by bronchial biopsy which does not carry enough tissue for frozen section and counting. This study is supplemented by estimating the prognostic significance of histological sub-types in the operable group and in a group of inoperable patients with extensive disease. These are usually treated by radiotherapy and/or chemotherapy. In all, 267 patients were studied including 105 treated by surgery. These patients attended King's College and Brompton Hospital, UK, between 1986 and 1989. With regard to proliferation marker Ki67 done for the surgical group, only patients with Ki67 scores of less than 5% did survive significantly longer than the rest. Histology did not make any significant contribution in determining prognosis in both operable and inoperable groups. Although follow-up is limited (mean 20 months), Ki67 antibody seems promising in identifying low and high grade disease in the initial stage of lung cancer. It may prove useful for category of patients with high scores to be placed on chemotherapy/radiotherapy. Results suggest that in the case of lung tumour, proliferative activity is a better prognostic indicator than histological type.

Adenocarcinoma↗

Detection of Mycobacterium tuberculosis in paraffin embedded intestinal tissue specimens by polymerase chain reaction: characterization of IS6110 element negative strains.

Tuberculosis is still one of the most widespread infection known to mankind. Although lung is the predominant site of disease, a sizeable population in Pakistan gets intestinal disease. Clinical presentation, radiologic and endoscopic examination provide clues to the diagnosis. However, a definitive diagnosis requires biopsy material with granulomas and/or caseation complemented by acid fast staining and culture. There are many occasions when biopsy material is scanty and even in some intestinal resection cases histologic evaluation fails to confirm or rule out tuberculosis. Therefore, an investigation was conducted to assess the efficacy of PCR in the detection of mycobacterial DNA in paraffin embedded intestinal tissue. In this study 12 histologically confirmed cases of intestinal tuberculosis and 2 cases with non specific inflammation but clinically suspected for abdominal tuberculosis were selected. One case of rectal polyp was included to serve as a negative control. M. tuberculosis DNA was amplified in 8 out of 12 histologically confirmed cases and in 2 cases diagnosed with non specific inflammation. Amplified products were obtained in 6 out of 10 PCR positive specimens with IS6110 region specific primers while 4 samples were negative, suggesting the absence of insertion sequence 6110 in these strains. However, amplification was obtained in these negative specimens with a second primer pair confirming them as M. tuberculosis complex species. On the basis of this study we conclude that; (1) Processed and paraffin embedded tissue material is suitable for PCR analysis, (2) PCR assay can be used to complement the diagnosis of intestinal tuberculosis especially in situations where a definite conclusion can not be drawn by conventional methods, (3) M. tuberculosis species lacking insertion sequence 6110 element are present in our population. Therefore, several primer pair sets should be included when applying PCR for the detection of mycobacterial DNA.

Adult↗

Kinetic aspects of Ki-67 antigen expression in a normal cell line.

Using a normal cell line derived from a human fetus, the disappearance and reappearance of the Ki-67-reactive antigen following modification of the cell cycle was observed and estimated immunohistologically. It was found that G1/G0 arrest induced by serum deprivation resulted in loss of the antigen in 24 h in all but a few (usually less than 10%) of cells. Return to normal medium and resumption of growth was accompanied by reappearance in 30 h. When entry into S-phase was prevented by desferrioxamine, reappearance of the antigen still occurred but only lasted for about 24 h. Inhibition of protein synthesis with cycloheximide also caused fading and eventual loss of immunostaining. In view of the ease with which this antigen becomes undetectable with cessation of protein synthesis and interruption of the cell cycle, we agree with those who advise caution in the use of Ki-67 to measure growth fraction in changeable cell populations such as tumours.

Blood↗

Growth fraction in lung tumours determined by Ki67 immunostaining and comparison with AgNOR scores.

Estimation of the growth fraction with the use of monoclonal antibody Ki67, which recognizes a nuclear antigen in proliferating cells, was compared with the nucleolar organizer region staining in 95 lung tumours. There was nuclear staining in most tumours; 12 tumours were negative. Cytoplasmic staining was observed in another seven tumours. The small cell carcinoma group had the highest mean Ki67 index (23.75); squamous carcinomas had a mean value of 15.71, adenocarcinomas 10.99, and large cell anaplastic 20.76. Carcinoids had few stained cells. Nucleolar organizer regions were demonstrated by the argyrophilic method (AgNOR). No correlation was found between Ki67 indices and AgNOR scores. Kinetic data obtained by the AgNOR technique were less discriminating in view of the overlap between scores of various groups including carcinoids. We conclude that use of the monoclonal antibody Ki67 is a more reliable method of assessing proliferative activity in lung tumours. This antibody may be effective in identifying slowly proliferating tumours which are less sensitive to chemotherapeutic agents.

Antibodies, Monoclonal↗