CLINICAL MEANING OF DNA CONTENT IN THE LONG-TERM BEHAVIOR OF FOLLICULAR THYROID-TUMORS - A 12-YEAR FOLLOW-UP

Objective: To find out if there was any correlation between the DNA an euploidy in benign tumours and in malignant follicular tumours of the thyroid and the progression of either disease. Design: Retrospective s tudy. Setting: University hospital. Subjects: 71 of 75 patients who ha d had cytofluorimetric nuclear DNA analyses done on their follicular t hyroid tumours during the period 1977-1980, and for whom clinical foll ow up data were available. Main outcome measures: Correlation between clinical course and finding of aneuploidy in original histological spe cimens. Results: Aneuploidy was found in 6/40 follicular adenomas, 3/1 7 adenomatous goitres, and in 13/14 follicular carcinomas. The patient s were examined after 12 years, when there had been no recurrences of the benign tumours. 5 of the patients with carcinoma had died of dista nt metastases, all of whom had aneuploid stemlines. There are, however , 8 patients with carcinomas and aneuploidy who are still alive with n o recurrences or metastases. Conclusions: DNA aneuploidy indicates nei ther the invasiveness nor the metastatic potential of follicular thyro id tumours, and does not distinguish between the minimally invasive (e ncapsulated) and highly invasive carcinomas.