Abstract 3213
Background
Photodynamic therapy (PDT) is one of actively developing modalities of cancer treatment. During PDT procedure systemically injected photosensitizer molecules are activated by laser irradiation in tumor location leading to generation of singlet oxygen which induces cytotoxic effect. In modern clinical practice PDT uses continuous wave irradiation. In such mode fast depletion of molecular (triplet) oxygen in tissue occurs leading to reduction of PDT efficiency. Previously we have shown that photodynamic treatment using pulse mode irradiation regimens could be more efficient in damaging tumor cells than standard PDT due to reoxygenation (Klimenko et. al., Photodiagnosis Photodyn Ther., 2016). In present study we have evaluated specially designed pulse mode PDT regimes on tumor model in vivo.
Methods
PDT pulse mode irradiation regimens were designed using physics and mathematical modelling. BALB/c male mice were subcutaneous injected into right flanks with CT26 murine colon carcinoma cells. At day ten after inoculation mice were randomized into 3 groups with 10 animals in each (control group, PDT at continuous wave irradiation mode – CW group, PDT at pulse irradiation mode – PM group) and PDT was made. The RadachlorinⓇ photosensitizer and «Lahta-Milon» semiconductor laser (662 nm) were used. After treatment the tumor size was estimated every two days. All experiments were performed in accordance with the animal ethics guidelines.
Results
We have designed new pulse mode irradiation regimens of PDT. We have shown that antitumor efficiency of PDT at pulse irradiation mode is much better than one at standard continuous wave irradiation mode. Median survival after day of treatment was 14 days in control group, 16 days in CW group and 28 days in PM group. In PM group 5 animals had total regress of tumor and progression free survival till the end of experiment (100 days after treatment) compared with only 1 animal in CW group. Thus, we can suggest that overall survival should be much higher in PM group.
Conclusions
We have demonstrated that PDT using pulse mode irradiation regimens is much more effective that PDT using standard regimens and leads to higher progression free and overall survival in mice with CT26 colon carcinoma.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.
Resources from the same session
5638 - Incidence of Vascular Thromboembolism Events in Cancer Patients Receiving Immunotherapy: A Single Institution Experience.
Presenter: Laura Gutiérrez Sainz
Session: Poster Display session 1
Resources:
Abstract
5182 - High Incidence of Venous Thromboembolic Events (VTE) in Patients with Diffuse Large B-Cell Lymphoma.
Presenter: Alaa Abufara
Session: Poster Display session 1
Resources:
Abstract
1504 - Weight Loss over Time in Non-Small Cell Lung Cancer: Results from a Landmark Analysis of 800+ Prospectively-Treated Patients
Presenter: Jennifer Le-rademacher
Session: Poster Display session 1
Resources:
Abstract
3972 - The prognostic significance of preoperative nutritional status in resected pancreatic ductal adenocarcinoma (PDAC).
Presenter: Salvatore Paiella
Session: Poster Display session 1
Resources:
Abstract
2313 - Impact of Timing and Technique of Gastrostomy Placement on the Outcome of Patients (pts) with Head and Neck Cancer (HNC)
Presenter: M Julia Lostes Bardaji
Session: Poster Display session 1
Resources:
Abstract
5219 - Clinical & nutritional determinants of quality of life in patients with incurable cancer
Presenter: Louise Daly
Session: Poster Display session 1
Resources:
Abstract
4075 - Loss of skeletal muscle mass during palliative chemotherapy is a poor prognostic factor in patients with advanced gastric cancer
Presenter: In Gyu Hwang
Session: Poster Display session 1
Resources:
Abstract
4159 - Impact of nutritional derangement on treatment outcome in advanced non-small-cell lung cancer (A-NSCLC) patients (pts).
Presenter: Ilaria Trestini
Session: Poster Display session 1
Resources:
Abstract
1210 - Sarcopenia and pretreatment anemia as prognostic factors for patients with localized muscle invasive bladder cancer treated by neoadjuvant chemotherapy and radical cystectomy
Presenter: Emilien Billon
Session: Poster Display session 1
Resources:
Abstract
2490 - Gender effect on the pharmacokinetics (PK) and pharmacodynamics (PD) of anamorelin (ANAM) in healthy volunteers and cancer patients with cachexia
Presenter: Stein Kaasa
Session: Poster Display session 1
Resources:
Abstract