Interobserver reproducibility with LiquiPrep liquid-based cervical cytology screening in a developing country.

OBJECTIVE: A modified liquid-based techniques known as the "LiquiPrep (LP) system" requires neither expensive equipment nor complicated specimen preparation. The aim of this study was to assess the applicability of the LP for use in a developing country. METHODS: Cervical cytology specimens were collected from 777 women, using the Cervex-Brush. The brush was first smeared on a glass side for conventional Papanicolaou (CP) stain, and then immersed in preservation fluid for LP preparation. Cytologic interpretations were classified into four categories: 1) no atypical cells, 2) atypical squamous epithelial cells (ASC), 3) definite epithelial cell abnormality, and 4) unsatisfactory specimen. Interobserver variability was tested using weighted kappa statistics. RESULTS: An LP specimen cost $9 per case compared to $3 per case for a conventional Pap smear. The time to learn the technique was only a few days. Forty six (5.92%) specimens by LP were unsatisfactory. The overall agreement between cytopathologists was 96.7% (weight kappa=0.62), with 95.6% (weight kappa=0.44) for the cases enrolled earlier, increasing to 97.9% (weight kappa=0.78) for the cases enrolled later. CONCLUSIONS: In summary, after a short learning curve, interobserver reproducibility of LP smear was near perfect. This feature of the LP, together with the relatively low cost and simple protocol, makes it quite suitable for cervical cytology screening in developing countries. Moreover, with this technique, some of each sample can be reserved for additional studies such as HPV detection and subtyping.

Prognostic value of p53 expression in early stage cervical carcinoma treated by surgery.

OBJECTIVE: To evaluate the prognostic significance of p53 protein expression in patients with early stage cervical carcinoma treated by surgery alone in a well-controlled study. METHODS: A matched case-control study was performed in patients with stage Ib-IIa cervical carcinoma who underwent radical hysterectomy with pelvic lymphadenectomy. Patients had neither lymph node metastasis nor involvement of the parametrium and surgical margins, and did not receive any adjuvant treatment. Cases included 30 patients who had tumor recurrence within 5 years after surgery; controls included 60 patients who were disease-free for at least 5 years after surgery. Cases and controls were within 10 years of age, had the same stage and tumor type, and underwent surgery on as close to the same date as possible. The tumor sizes of cases and controls were within 1 cm of each other. Expression of p53 protein was studied by immunohistochemistry. Expression was considered positive when at least 10% of tumor cells showed nuclear staining. RESULTS: No significant difference of p53 expression was observed between the case group and the control group (33% versus 40%). High histologic grade of tumors and lymphovascular space invasion were significantly associated with tumor recurrence in multivariable analysis (p=0.012 and 0.014, respectively). CONCLUSION: In this study, expression of p53 did not correlate with tumor recurrence. Immunohistochemistry for p53 protein appears to provide no prognostic information in the patients with early stage cervical cancer treated by surgery.

Epidemiologic study of 112 osteosarcomas in Chiang Mai University Hospital, Thailand.

OBJECTIVE: To summarize the epidemiologic features of osteosarcoma. MATERIAL AND METHOD: One hundred and twelve cases of osteosarcoma were collected retrospectively from the Pathology Department of the Chiang Mai University Hospital, Thailand between 1995 and 2005. RESULTS: From the present study, there were 14 cases in average, annually, since 2002. Seventy-seven percent of cases were from the upper north Thailand, the region serviced by Chiang Mai University Hospital. The male:female ratio was 1.3:1 and 86% of cases occurred within the first three decades of life. The majority of cancer was found in the long bones (83%) and the majority of lesion was around the knee (68%). Conventional and telangiectatic osteosarcoma accounted for 85% and 8% of cases, respectively. CONCLUSION: The authors have summarized some epidemiologic features of osteosarcoma. The authors found the relatively high frequency of telangiectatic osteosarcoma around the upper part of north Thailand These results give an initial picture to the national health provider section for planning personnel, medical and supportive equipment, and funding for the care of osteosarcoma patients. Nationwide co-operation in registering osteosarcoma patients would provide more complete data on this tumor in Thailand and promote the establishment of standardized treatment protocols.

Chromogenic in situ hybridization using routine tissue sections: MYCN in neuroblastoma.

Background: Amplification of the MYCN (myc myelocytomatosis viral related oncogene, neuroblastoma derived) gene in neuroblastoma is associated with a poor prognosis. Methods for estimating MYCN gene copy number that are based on pooled cells do not address copy number heterogeneity at the cell level and can underestimate or even miss amplification. MYCN copy number can be directly assessed by fluorescence in situ hybridization, but evaluation of tissue histology is difficult if not impossible. Objective: This paper reviews chromogenic in situ hybridization (CJSH) as it applies to the MYCN gene in neuroblastoma. We compare this technique to other methods for determining gene copy number and highlight the advantages of CISH. Methods: We have developed a chromogenic method for in situ hybridization (CISH) that enables us to determine MYCN copy number on an individual cell basis. This technique uses light microscopy on routine paraffin sections, and therefore allows simultaneous assessment of tumour histology. Results: In a previous study, CISH identified 100 % of the cases that were known to be amplified by other techniques and proved to be more sensitive than Southern blotting or the quantitative DNA polymerase chain reaction. The MYCN copy number is generally believed not to vary within a tumour, nor between tumour samples, including primary vs. metastases, and pre-and post-treatment specimens. However, we found heterogeneity from cell to cell, with ~30 % of amplified tumours showing >50 % variation in MYCN copy between cells. Conclusion: For detection of gene amplification, CISH has all the advantages of FISH but in addition, needs no special microscopy or image capturing systems, and preparations are permanent. In the case of neuroblastoma, CISH has disclosed considerable heterogeneity in MYCN copy number between cells in a tumour. Heterogeneity reflects different tumour clones and its role has been under-recognized in neuroblastoma biology. Additional studies are needed to investigate the significance of tumour heterogeneity in neuroblastoma, and whether the aggressive (i.e., MYCN-amplified) clones are more likely to metastasize, survive treatment modalities, and ultimately kill the patient.

Spectrum of bone tumors in Chiang Mai University Hospital, Thailand according to WHO classification 2002: A study of 1,001 cases.

OBJECTIVE: The aim of the present study was to determine the spectrum, frequency and demographics of bone tumors. MATERIAL AND METHOD: A retrospective study of the 1,001 bone tumor specimens from the files at the Pathology Department of the Chiang Mai University Hospital, Thailand from 2000 to 2004. RESULTS: From the study, 41 were non-neoplastic mass lesions, and 960 were neoplastic, with 856 (89%) as primary and 104 (11%) as metastatic tumors. In the primary tumor group, 654 (76%) cases were of hematologic origin, and 202 (24%) were non-hematologic. The most common benign bone tumors were giant cell tumor (n = 37), osteochondroma (n = 25), and chondroma (n = 15). The most common malignant bone tumors were lymphoma-leukemia (n = 583), metastatic malignancy (n = 104), plasma cell myeloma (n = 71), and osteosarcoma (n = 58). CONCLUSION: The present study showed a higher frequency of osteosarcoma (68%), lower frequencies of chondrosarcoma (12%) and Ewing sarcoma (4%) among primary non-hematologic malignant bone tumors when compared with similar studies based on Western patients. Whether these differences reflect differences in the ethnic population or in practice patterns remains to be determined