MKI67 and cancer: Foglietta et al. tested 5-ALA-SDT in a breast cancer rat model, where the SDT-treated group showed a significant reduction (p ≤ 0.0001) in tumor size compared to the untreated group and the groups treated with 5-ALA and ultrasound alone, and a strong decrease (p ≤ 0.0001) in Ki67 protein expression was the most important feature of the SDT-treated cancer tissues.