G. Hermann et al., INTERVAL CHANGES IN NONPALPABLE BREAST-LESIONS AS AN INDICATION OF MALIGNANCY, Canadian Association of Radiologists journal, 46(2), 1995, pp. 105-110
OBJECTIVE: To determine whether the patterns of interval changes in no
npalpable breast lesions can be used to determine malignancy. PATIENTS
AND METHODS: The authors reviewed the records for 128 nonpalpable bre
ast lesions detected by mammography between March 1990 and May 1992 fo
r which previous imaging studies were available. Changes in size, dens
ity and contour of the 59 masses and changes in size, number, configur
ation and pattern for the 69 cases involving microcalcifications were
determined from comparison of the current mammograms with the earlier
imaging studies, obtained 6 to 42 months previously. These findings we
re correlated with the pathological diagnosis based on needle localiza
tion and excisional biopsy. RESULTS: Twelve (55%) of the 22 new masses
and 15 (48%) of the 31 masses that changed were malignant, but none o
f the 6 masses that did not change were malignant (chi2 test, p < 0.01
). All of the 31 masses that changed increased in size (and of these,
15 [48%] were malignant). In addition, 14 (45%) of the masses that cha
nged exhibited increased density (and of these 9 [64%] were malignant)
, and 11 (35%) became irregular (and all of these were malignant). Eig
ht (47%) of the 17 cases of new calcifications, 18 (43%) of the 42 cas
es of calcifications that changed and none of the 10 cases of unchange
d calcifications were malignant (chi2 test, p < 0.01). Twelve (44%) of
the 27 calcifications that changed in area and 14 (40%) of the 35 tha
t changed in number were malignant. Fifteen (60%) of the 25 calcificat
ions that changed from scattered to grouped and 8 (53%) of the 15 that
changed from punctate to linear were malignant. CONCLUSION: A change
in the density or contour of a mass is a fairly definite sign of malig
nancy. The authors conclude that interval observation is a good method
of detecting malignancy in breast masses but is less reliable for det
ecting malignancy in calcifications.