In the sentence extracted from biomedical literature, identify all the disease entities. The required answer format is the same sentence with HTML <span> tags to mark up specific entities. 
### Entity Markup Guides:
Use <span class="disease"> to denote a disease.

### Input Text: In the present study , leukocyte DNA from 143 patients with familial clustering of breast and / or ovarian cancer and tumour DNA from 96 breast carcinomas were screened for base mutations in the estrogen receptor gene ( ESR ) .
### Output Text:
In the present study , leukocyte DNA from 143 patients with familial clustering of <span class="disease">breast and / or ovarian cancer</span> and <span class="disease">tumour</span> DNA from 96 <span class="disease">breast carcinomas</span> were screened for base mutations in the estrogen receptor gene ( ESR ) . 