C. Bergstrom et al., FACTORS INFLUENCING THE ESTIMATES OF PROLIFERATIVE LABELING INDEXES IN RECTAL-CANCER, Radiotherapy and oncology, 46(2), 1998, pp. 169-177
Citations number
28
Categorie Soggetti
Oncology,"Radiology,Nuclear Medicine & Medical Imaging
Purpose. A detailed analysis was undertaken of some of the factors inf
luencing the estimate of the labelling index (LI). Materials and metho
ds: Thirty-three human rectal carcinomas were studied for their prolif
erative activity as measured by the fraction of cells labelled with a
single injection of IdUrd 1-8 h before surgical resection. Adjacent sp
ecimens were stained both for histological examination and for flow cy
tometry (FCM) assessment of labelled nuclei. Results: Two major differ
ences were found. The superficial parts of each tumour almost always h
ad significantly higher LI values than the deep part (34 versus 21%),
yielding an average LI of 27%. The flow cytometry average value was mu
ch lower (17%). This was partly due to the influence of diploid tumour
s. There was a marked heterogeneity in the values, both within tumours
, between tumours and between techniques. The average LI for the whole
group differs by a factor of three, depending on the method of assess
ment. Conclusions: All these values indicate a varying but rapid proli
ferative turnover of cells, surprisingly being more marked in the supe
rficial region, i.e. the opposite from the proliferation pattern of th
e normal rectal mucosa. A biopsy, if taken from the superficial part o
f the tumour, would therefore be biased toward higher values. This has
implications for biopsy sampling for cell kinetic analysis. Histologi
cal assessment avoids the contaminating effect of stromal cells, allow
s architectural arrangements to be detected and is presumably a more r
ealistic representation of proliferative activity. (C) 1998 Elsevier S
cience Ireland Ltd.