Large performance variation does not affect outcome in the Finnish cervical cancer screening programme.

OBJECTIVE: Cytology screening for prevention of cervical cancer can reduce incidence and mortality by more than 80% in settings with good organization and rigorous quality control. Audit studies are essential for reaching and maintaining a high quality of screening. The aim of this study was to evaluate variation in performance indicators by screening laboratory and assess the impact on the effectiveness of screening as indicated by cervical intraepithelial neoplasia grade 3 and above (CIN3+) rates after a negative screen. METHODS: Seven cytology screening laboratories operating during 1990-1999 with a total of 953 610 screening tests performed were included in the study. By linking screening and cancer register files, all cases of CIN3+ diagnosed in the screened population were identified. For 395 CIN3+ cases with a preceding negative screen and 787 controls, a re-evaluation of smears was undertaken to uncover false negative screening tests. Performance parameters and rates of CIN3+ after a negative screen were analysed for interlaboratory heterogeneity. RESULTS: The rates of follow-up recommendations and referrals varied by up to 3.6- (2.8-10.2%) and 4.0-fold (0.03-0.12%), respectively. CIN1, CIN2 and CIN3+ screen detection rates differed by up to 8.5- (0.02-0.17%), 5.4- (0.05-0.25%) and 3.3-fold (0.05-0.18%). False negative rates determined by re-evaluation showed up to 2.1-fold differences (29-62%). Rates of CIN3+ after a negative screen (0.023-0.048%) and as a proportion of total CIN3+ (15-31%) in the screened population were low and did not vary significantly. CONCLUSIONS: There were large variations in the sensitivity-specificity trade-off between laboratories, reflected in all performance indicators as well as in the test validity estimates of the re-evaluation phase, but not in screening effectiveness. Even though performance variations do not always have an impact on the effectiveness of screening, they lead to variations in cost, treatment and psychological burden, and should be addressed.

Tenascin-C in primary Merkel cell carcinoma.

BACKGROUND/AIMS: Merkel cell carcinoma (MCC) is a rare malignant cutaneous neuroendocrine tumour that mostly affects the elderly. It shows rapid progression of the primary tumour, together with a vertical growth pattern into the underlying subcutaneous tissue. Metastatic dissemination to regional lymph nodes is early and frequent. Tenascin-C (Tn-C) is a large extracellular matrix glycoprotein that is expressed in various benign and malignant processes. Expression of Tn-C is also associated with invasion and cellular proliferation, and is often downregulated in fully evolved advanced carcinomas. In previous studies, Tn-C expression correlated with prognosis in tumours of different origin. METHODS: Immunohistochemistry was used to investigate the expression of Tn-C in 25 MCC specimens and to evaluate the prognostic importance of this glycoprotein. RESULTS: Seventeen samples expressed Tn-C. Staining was mainly seen in the invasion borders and within the connective tissue septae inside the tumours. The expression of Tn-C correlated significantly with large tumour size. There was also frequent expression of Tn-C in primary tumours with metastatic dissemination. Most of the Tn-C negative samples were of small size. CONCLUSIONS: Tn-C expression seems to increase with tumour size and malignant behaviour. Expression was slightly enhanced in tumours with high proliferative indices. Expression is seen mainly in areas of invasive growth and, in this respect, resembles that of other invasive tumours.

de la Chapelle dysplasia.

Since the description by de la Chapelle and colleagues of two sibs with a unique skeletal dysplasia, two additional cases have occurred, one in the original Finnish family and one sporadic patient born to unrelated parents of Belgian descent. The original Finnish family has later had a fourth child, a normal daughter who was found to be unaffected upon radiographic examination in the 19th week of gestation. These additional findings are compatible with recessive inheritance. Physical features common to these four patients include cleft palate, small thorax, moderately severe micromelia with small hands, and equinovarus deformity. In each case, the ulnae and fibulae were reduced to an almost triangular osseous remnant. Other long bones were short and bowed. Neonatal death occurred in all cases and may be attributed to a consistent triad of respiratory tract malformations: laryngeal stenosis, tracheobronchomalacia, and pulmonary hypoplasia. Clinical and radiographic features are sufficiently unique to distinguish de la Chapelle dysplasia from other disorders in the spectrum of neonatal lethal osteochondrodysplasias. Lacunar halos were identified as a distinctive histopathologic feature also observed in achondrogenesis but not in several other skeletal dysplasias.

Evaluation of the toxicity and carcinogenicity of hair dyes in Swiss mice.

The chronic toxicologic and carcinogenic potential of two oxidative and twelve non-oxidative hair dyes has been evaluated. The dyes were skin painted up to 3 times weekly on groups of 60 male and 60 female Eppley Swiss mice. Treatments were carried out for 20 months followed by terminal sacrifice. Nine months after treatments were initiated an intermediate sacrifice of ten mice per sex per group was carried out. Body weights and survival differed little between appropriate male and female treatment and control groups. Differences between treated and control groups in absolute and relative liver and kidney weights and in hematological and urinary values were not considered to be indicative of toxicologic effects. Microscopic examinations of the skin revealed occasional hyperplasia, necrosis, ulceration and other lesions not significantly increased by dye treatment. Chronic inflammation of the skin was observed in the control and treated mice and was significantly increased by one non-oxidative dye. The predominant tumors diagnosed were liver hemangioma, lung adenoma and malignant lymphoma. There was a statistically significant increase in the incidence of malignant lymphoma in female mice in 3 treated groups when compared to control group 2, but the differences were not significant when these groups were compared to control group 1. In addition the values in these 3 groups were within the range of control values for this tumor in female mice in the Eppley colony. No other tumors occurred at significantly increased frequencies in treated mice. We conclude that toxicological and carcinogenic effects were not clearly induced by the hair dye formulations.

Myositis ossificans following forcible manipulation of the leg. A rabbit model for the study of heterotopic bone formation.

The right hind limbs of forty-four rabbits were immobilized with the knee in extension for as long as five weeks, except for a daily session of forcible mobilization lasting five minutes. Within five weeks there was progressive heterotopic-bone formation in the quadriceps muscle. The roentgenographic and histological changes were similar to those seen in human myositis ossificans.

Defects of the central nervous system in Finland. IV. Associations with diagnostic x-ray examinations.

Based on the Finnish Register of Congenital Malformations a search was undertaken to find possible associations between defects of the CNS and diagnostic x-ray examinations of the mother during pregnancy as well as pelvic x-ray examinations prior to pregnancy. Time-area--matched pregnancies and polydactylic children were used as controls. The risk of having a microcephalic child was increased for mothers with pelvic x-ray prior to pregnancy, but the number of discordant pairs was small. Of the examinations performed during pregnancy, fetal x-ray was significantly more common among mothers who delivered a CNS-defective child. No associations were observed for other kinds of examinations.