Skip to main content

Table 2 Characteristics of DMBA-induced mammary tumors in lean and obese female Zucker rats

From: Obesity promotes 7,12-dimethylbenz(a)anthracene-induced mammary tumor development in female zucker rats

Characteristic

Lean (n = 28)

Obese (n = 25)

Tumor onset

   Day of first tumora

86

49**

   Day at 25% tumorsb

118

66**

   Pc

 

0.001

Tumor incidence

   % of rats with tumorsd

32

68**

   Pe

 

0.001

Multiplicityf

1 (1–4)

2 (1–4)

   Pc

 

0.42

Tumor weight (g)g

0.37 (0.01–6.44)

0.42 (0.05–7.70)

   Pc

 

0.47

Rats with tumorsh

   IDP

2 (7%)

4 (16%)

   DCIS

5 (19%)

6 (24%)

   IDC

2(7%)

7 (28%)*

  1. aPost-DMBA (7,12-dimethylbenz(a)anthracene) day at which the first mammary tumor was detectable by palpation. bPost-DMBA day at which the probability of tumor development was 25%. cP values based on generalized Wilcoxon test. dPercentage of rats with at least one mammary tumor. eP values based on the Fisher's exact test. fMedian number of tumors in tumor bearing rats (minimum-maximum in parentheses). gMedian tumor weight (minimum-maximum in parentheses). hNumber and percentage of rats with at least one tumor graded as intraductal proliferation (IDP), ductal carcinoma in situ (DCIS), or invasive ductal and lobular carcinoma (IDC), as described in the Materials and method section. **P < 0.001, *P < 0.05.