Intratumor photosensitizer injection for photodynamic therapy: Pre-clinical experience with methylene blue, Pc 4, and Photofrin

Timothy M. Baran; Thomas H. Foster

doi:10.1117/12.2229544

1 March 2016 Intratumor photosensitizer injection for photodynamic therapy: Pre-clinical experience with methylene blue, Pc 4, and Photofrin

Timothy M. Baran, Thomas H. Foster

Author Affiliations +

Proceedings Volume 9694, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXV; 969418 (2016) https://doi.org/10.1117/12.2229544
Event: SPIE BiOS, 2016, San Francisco, California, United States

Abstract

Intravenous administration of some photosensitizers, including the FDA-approved Photofrin, results in significant systemic photosensitivity and a 2-3-day drug-light interval. Direct intratumor injection of photosensitizer could potentially eliminate these negative aspects of photodynamic therapy (PDT), while requiring a lower photosensitizer dose to achieve comparable drug concentration in the target tissue. We performed PDT using intratumor injection of 3 photosensitizers, methylene blue (MB), Pc 4, and Photofrin, in mouse tumor models. After a 0-15 minute drug-light interval, illumination was delivered by appropriate diode lasers. For animals receiving MB or Pc 4, surface illumination was delivered using a microlens-terminated fiber. For animals receiving Photofrin, interstitial illumination was delivered by a 1 cm diffuser. In animals receiving MB or Pc 4, tumor dimensions were measured daily post-PDT, with a cure being defined as no palpable tumor 90 days post-treatment. For Photofrin, animals were sacrificed 24 hours post-PDT and tumors were excised, with samples HE stained to assess PDT-induced necrosis. 55% of tumors were cured with MB-PDT, and significant tumor growth delay (p=0.002) was observed for Pc 4. For Photofrin PDT, the mean necrosis radius was 3.4±0.8 mm, compared to 2.9±1.3 mm for systemic administration, which was not a significant difference (p=0.58). Intratumoral injection of the photosensitizers methylene blue, Pc 4, and Photofrin is feasible, and results in appreciable tumor response. Further investigation is necessary to optimize treatment protocols and assess the systemic photosensitivity induced by intratumor injection.

Citation Download Citation

Timothy M. Baran and Thomas H. Foster "Intratumor photosensitizer injection for photodynamic therapy: Pre-clinical experience with methylene blue, Pc 4, and Photofrin", Proc. SPIE 9694, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy XXV, 969418 (1 March 2016); https://doi.org/10.1117/12.2229544

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available