Objective:

To investigate the relationship among MR apparent diffusion coefficiency (ADC)

tumor size and Ki-67 expression in non-mass-like breast carcinoma.

Methods:

A total of 80 cases diagnosed as breast cancers by pathologic examination underwent MRI prior to surgery. All cases showed non-mass-like enhancemen

t in dynamic contrast-enhanced MRI. ADC value and tumor size were measured respectively. The expression of Ki-67 in tumor tissue was assayed by immunohistochemical staining. t test and Spearman rank correlation were used to evaluate the correlation among ADC value

tumor size and Ki-67 expression. The receiver operating characteristic (ROC) curve was applied to get the best threshold of tumor size to judge Ki-67 expression.

Results:

The ADC values in Ki-67 positive and negative groups were (1.0140.181)10

-3

mm

2

/s and (1.0240.142)10

-3

mm

2

/s

respectively. The tumor sizes in Ki-67 positive and negative expression groups were (5.121.71) cm and (3.580.89) cm

respectively. There was significant difference in tumor size between Ki-67 positive and negative groups (

t

=4.741

P

＜0.05)

and the tumor size was positively correlated with Ki-67 expression

(r

=0.366

P

＜0.05). The best threshold of tumor size to judge Ki-67 expression was 4.1 cm by ROC curve. However

there was no significant difference in ADC value between Ki-67 positive and negative groups (

t

=-0.189

P

＞0.05)

and ADC value was not correlated with Ki-67 expression (

r

=-0.029

P

＞0.05).

Conclusion:

Tumor size may be correlated with Ki- 67 expression in non-mass-like breast carcinoma

and formulate the treatment and it can help to prognosis evaluation for patients.