The rising incidence of stage 1 seminoma; a reflection of earlier diagnosis of germ cell cancer of the testis in last 20 years

Abstract

4521 Background: The last 20 years has seen a dramatic change in outcome of treating metastatic testis cancer, coinciding with a marked increase in incidence. The reasons for this increase remain unclear. In an attempt to investigate this further, this abstract reviews pathological and clinical staging in patients registered in the Anglian Germ Cell Tumour Group data base between 1983 and 2002. Methods: Clinicians from 7 treatment centres (St Bartholomew'ss, Oldchurch, Southend, Colchester, Ipswich, Norwich and Cambridge) prospectively registered cases of testicular cancer in a central data base between 1983 and . The patients were divided into 3 time periods (1983–1988, 1989–1995, 1996–2002). The relative incidence of seminoma vs non seminoma and local vs metatatic disease were compared.The size of the stage 1 tumours were assessed and recorded from 2 of the treatment centres over the time period. Results: During the time of study, stage 1 seminoma increased significantly from 34% to 44% to 52%, while metastatic non seminoma decreased from 31% to 23% to 16% (p<0.05 for both). The relative incidence of metastatic seminoma and stage 1 non-seminoma remained unchanged. The mean age of the patients at the time of presentation of the tumour did not alter over the 20 year period. For patients with stage I disease, there was a reduction in the average size of the primary tumour (4.7 to 3.9 cms) during this period. Conclusions: The reduction in tumour size and the decreased frequency of patients with metastases could be a true product of increasing patient education about early diagnosis. The relative increase in the incidence of seminoma is an interesting observation and requires further investigation. These findings could be an artefact of patient referral data from selected centres, and needs validating by prospective cancer registrations, which is now in progress. No significant financial relationships to disclose.