Photodynamic therapy (PDT) is a treatment modality that can be indicated for several cancer types and precancer lesions. One of the main applications of PDT is the treatment of superficial skin lesions such as basal cell carcinoma, Bowen's disease and actinic keratosis. Three elements are necessary in PDT, a photosensitizer (PS); light at specific wavelength to be absorbed by the PS, and molecular oxygen. A typical PS used for skin lesion is protoporphyrin IX (PpIX), which is an intrinsic PS; its production is stimulated by a pro-drug, such as 5-aminolevulinic acid (ALA). Before starting a treatment, it is very important to follow up the PpIX production (to ensure that enough PS was produced prior to a PDT application) and, during a PDT session, to monitor its photodegradation (as it is evidence of the photodynamic effect taking place). The aim of this paper is to present a unique device, LINCE (MMOptics -São Carlos, Brazil), that brings together two probes that can, respectively, allow for fluorescence imaging and work as a light source for PDT treatment. The fluorescence probe of the system is optically based on 400 nm LED (light emitting diodes) arrays that allow observing the fluorescence emission over 450 nm. The PDT illumination probe options are constituted of 630 nm LED arrays for small areas and, for large areas, of both 630 nm and 450 nm LED arrays. Joining both functions at the same device makes PDT treatment simpler, properly monitorable and, hence, more clinically feasible. LINCE has been used in almost 1000 PDT treatments of superficial skin lesions in Brazil, with 88.4% of clearance of superficial BCC.

Cancer is considered one of the major public health problems worldwide. Among the therapeutic approaches investigated and used so far, the combined use of photothermal (PTT) and photodynamic (PDT) therapies have shown promising results for in vivo studies. The mechanisms of actions of both therapies are based on use of a chemical entity and a source light with an appropriate wavelength, and, in PDTs case, also molecular oxygen (O2). Moreover, the combined use of PTT and PDT may present a synergic effect on the elimination of solid tumor and metastasis. Herein, we review the past 5 years (2016–2020) regarding the combined use of PTT and PDT and carbon nanomaterial platforms as photosensitizers and photothermal agents against cancer (in vivo evaluation). We intend to highlight the most important and illustrative examples for this period. Additionally, we report the mechanisms of action of PTT and PTT and the general physical/chemical properties of carbon nanomaterial platforms used for this therapeutic approach.

Graphical AbstractBrief description of the procedures carried out in this study. In vivo and in vitro antibacterial photodynamic therapy (aPDT) studies, where aPDT mediated by C-DOTS and blue LED light against S. aureus was evaluated.

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Along the past years, a national program to implement photodynamic therapy (PDT) for nonmelanoma skin cancer (NMSC) was performed over the Brazilian territory. Using a strategy involving companies, national bank, and medical partners, equipment, medication, and protocols were tested in a multicenter study. With results collected over 6 years, we could reach a great deal of advances concerning the use of PDT for skin cancer. We present the overall reached results of the program and discuss several aspects about it, including public politics of treatment. A discussion about advantages of this technique within conditions of health care is placed, comparing PDT with surgery, including an analysis about the implementation of PDT in countries in development as Brazil, considering not only technical but social aspects, as the distribution of medical doctor in the Brazilian territory. The program resulted in a huge dissemination of PDT in Brazil and many countries in Latin America, in a partnership among public politics, universities, companies, and hospitals and clinics and in the insertion of national technologies as option to treat NMSC. Consequence of the program is mainly the continuation of the use of PDT in Brazil and many countries in Latin America.

Photodynamic therapy (PDT) has been used for local treatment of several types of tumors. Light penetration of biological tissue is one limiting factor in PDT, decreasing the success rates of the treatment of invasive and solid tumors. In those cases, a possible solution is to use interstitial PDT, in which both diffuser optical fibers are inserted into the tumor. The uniformity of the diffuser emission plays a crucial role in planning the delivery of the appropriate light fluence and in ensuring treatment success. In this study, we characterized a diffuser optical fiber concerning its homogeneity. We showed that the diffuser emission can be inhomogeneous and that the necrosis generated by interstitial PDT using such a diffuser for illumination is asymmetrical in volume as a result. This observation has relevant consequences in achieving success in PDT and phototherapies in general, as the delivered light fluence depends on adequate previous knowledge of the irradiation profile.

Introduction: Cancer is the second leading cause of death globally and is responsible, where about 1 in 6 deaths in the world. Therefore, there is a need to develop effective antitumor agents that are targeted only to the specific site of the tumor to improve the efficiency of cancer diagnosis and treatment and, consequently, limit the unwanted systemic side effects currently obtained by the use of chemotherapeutic agents. In this context, due to its unique physical and chemical properties of graphene oxide (GO), it has attracted interest in biomedicine for cancer therapy. Methods: In this study, we report the in vivo application of nanocomposites based on Graphene Oxide (nc-GO) with surface modified with PEG-folic acid, Rhodamine B and Indocyanine Green. In addition to displaying red fluorescence spectra Rhodamine B as the fluorescent label), in vivo experiments were performed using nc-GO to apply Photodynamic Therapy (PDT) and Photothermal Therapy (PTT) in the treatment of Ehrlich tumors in mice using NIR light (808 nm 1.8 W/cm2). Results: This study based on fluorescence images was performed in the tumor in order to obtain the highest concentration of nc-GO in the tumor as a function of time (time after intraperitoneal injection). The time obtained was used for the efficient treatment of the tumor by PDT/PTT. Discussion: The current study shows an example of successful using nc-GO nanocomposites as a theranostic nanomedicine to perform simultaneously in vivo fluorescence diagnostic as well as combined PDT-PTT effects for cancer treatments.

Skin cancer is the cancer type with the highest incidence in the world. Its diagnosis requires a specialist physician, with expertise in skin diagnostics. Thermography is a noninvasive technique based on the detection of infrared emission that is completely safe to humans. In this study, thermal images of clinically similar lesions were registered and analyzed aiming to provide a noninvasive diagnostic information for discrimination of: basal cell carcinoma versus intradermal nevus, squamous cell carcinoma versus actinic keratosis, and melanoma versus pigmented seborrheic keratosis. Thermal images were analyzed using a MATLAB® routine to evaluate statistical, histogram, and filtering metrics of each image, and a support vector machine classifier was used to discriminate the lesions based on those metrics values. Actinic keratoses and squamous cell carcinoma showed distinct average temperatures, whereas the other pairs of lesions presented similar temperatures. Nevertheless, the benign lesions showed higher definition of borders detection than malignant lesions, as a general rule. The results showed that support vector machine classifier has great ability for discrimination of clinically similar lesions based on their thermal images, suggesting that the thermography can be used as an auxiliary tool for the diagnosis of skin malignant lesions.