Histological features, DNA content and prognosis of breast carcinoma found incidentally or in screening

Abstract

Summary Histology features, the nuclear DNA content and prognosis of 42 female breast carcinomas found in a physical examination based screening, 54 breast cancers found incidentally by medical personnel, and 274 breast cancers first suspected by the patient were compared. There was no significant difference in the distribution by primary tumour size (P = 0.08) or histological type (P = 0.87) of breast cancer between the screen-detected and 139 self-suspected cancers of women with similar mean age and living at the same time in the same city, but the screen-detected carcinomas were better differentiated (P = 0.0002), and had less mitoses (P =0.008), less tumour necrosis (P = 0.004) and DNA aneuploidy (P = 0.01), smaller S-phase fractions (P = 0.009), less axillary metastases (P = 0.04), and had better outcome (P = 0.005) than self-suspected carcinomas. These parameters did not differ significantly between the screen-detected and incidentally found cancers, but incidental cancers had more often axillary metastases (P = 0.02). The results indicate that screen-detected breast carcinomas have favourable biological features suggesting low degree of malignant potential.

Aggressiveness of breast cancers found with and without screening.

“…In one study 37 breast cancers detected by mammography were found to have smaller S phase fractions and less DNA aneuploidy than 60 control cancers diagnosed a few years earlier, but no adjustment for size of the cancers was made.5 Similarly, in another study 42 breast cancers found in a palpation based screening were found to have less aggressive histological and cytometric features than in clinical controls. 16 The lower malignant potential of screen detected breast cancer may decrease the efficiency of screening in saving lives and may at least partially explain why significant reductions in mortality have not always been achieved by screening.44 If treatment of breast cancer is based only on the size of the primary tumour many women with cancer detected by screening may be overtreated.…”

Tumour development, histology and grade of breast cancers: Prognosis and progression

“…(2) Other studies have indicated a difference between screen-detected and clinically diagnosed cancers with respect to immunohistochemical measures and DNA ploidy (Cowan et al, 1991;Joensuu et al, 1991;Rajakaria and Walker, 1995).…”

C‐erbB‐2 oncoprotein in screen‐detected breast carcinoma: An immunohistological study

“…Our findings would suggest that the great majority of impalpable screen-detected lesions detected so far are probably of low malignant potential. This is in agreement with several other recent studies using more convential morphological criteria, eg., tumour size, nodal status and histological type (Du@ et al, 1991;Joensuu et al, 1991;Klemi et al, 1992;Uyterlinde et al, 1991), as well as DNA ploidy studies (Joensuu et al, 1991;Uyterlinde et al, 1991). It is not known whether the lower prevalence of c-erbB-2 amplification in these tumours is the result of an innate property which would have not changed if the tumours had been allowed to grow further, or whether it is related to the small size of the tumours, so that amplification might have occurred in more lesions if they had been allowed to attain a larger size.…”