Photodynamic therapy approach for central lung cancer

Background: This study aimed to evaluate the efficacy and safety of chlorine series photosensitizer for central lung cancer photodynamic therapy (PDT). Methods: The TMA clinic conducted PDT for 41 patients with central lung cancer. 2 hours before the procedure patients were intravenously injected with chlorine series (Photolon, photoditazin) at a dose of 0.7-1.9 mg / kg. PDT was performed by laser installation with a wavelength corresponding to the absorption spectrum of the photosensitizer, the power supplied doses ranged from 0.4 W to 1.6 W, the laser energy density of 100-300 J/cm2. Endoscopic procedures were performed using video system OLYMPUS EVIS Exera 160. For anesthesia local anesthetic lidocaine and general sedation were used. Results: The immediate results were traced in 37 patients. Terms of monitoring of patients ranged from 5 days to 3 years. As an estimate of the treatment effect we used data bronchoscopy, spirometry, radiological picture, as well as the dynamics of patient complaints. During bronchoscopy, at 5-7 days, 8 (21.6%) patients had superficial necrosis of the tumor, in 27 (73%) a deep tumor tissue necrosis, 6 of them showed damage to surrounding healthy tissue, and in 2 patients reaction from the tumor tissue was observed. During bronchoscopy, performed 1 month after PDT, complete tumor regression was observed in 23 (62.2%), partial response - in 12 (32.4%) patients, 2 patients with no revealed tumor shrinkage. If the energy density of the laser radiation (E) is less than 200 J/cm2, the frequency marked necrotic changes every 5-7 days after PDT was observed in 5 (45%) of 11 patients after the application dose of 200 or more J/cm2 at 22 (84.6%) of 26 patients. Similar results were obtained after evaluating the degree of tumor regression 1 month after PDT: complete regression at E, is less than 200 J/cm2 was achieved in 2 (18.2%) of 11 patients at E greater than or equal to 200 J/cm2 - at 21 (80.8%) of 26 patients (p < 0.001). Clinically, the implementation effect of photodynamic therapy was shown in the complete cessation of hemoptysis in 75% of patients, reducing cough noted in 55% of patients, reducing breathlessness - 47% of patients with these symptoms. Positive dynamics in the form of X-ray resolution of atelectasis and eliminate air disturbances was observed in 84% of cases. Spirometry before and after PDT procedure was conducted in 14 patients with tumor obturation large bronchi. In 4 patients with tumor stenosis of the main bronchus increase in lung capacity after the PDT, procedure ranged from 6 to 33% (on average - 20%), 8 patients with bronchial obstruction share - from 3 to 9% (on average 6%). In all patients, administration of a photosensitizer proceed without side reactions, and tolerability of these drugs has been satisfactory. Manifestations of cutaneous phototoxicity, subject to light conditions for 3 days after PDT was observed. The most common complications of PDT procedure are local inflammatory processes. Of the 39 patients observed in 5 developed pneumonia of mild severity, 4 patients - endobronchitis accompanied characteristic clinical and radiological symptoms, and endoscopy was defined focal edema and hyperemia of bronchial mucosa on the affected side. The most common complications of PDT procedure are local inflammatory processes. In the course of studies to reduce the frequency of inflammatory complications, we decided to use broad-spectrum antibiotics immediately after the PDT procedure for 5-7 days, which greatly reduced the incidence of bronchitis and pneumonia. Conclusions: Photodynamic therapy with chlorine series has a high clinical efficacy. The immediate results of PDT using Photolon are comparable to Photoditazin results from the use of first generation photosensitizers, drugs are safe to use and do not exhibit pronounced skin phototoxicity. Legal entity responsible for the study: TMA Funding: None Disclosure: All authors have declared no conflicts of interest.