Place of cryotherapy, brachytherapy and photodynamic therapy in therapeutic bronchoscopy of lung cancers

Cryotherapy, brachytherapy and photodynamic therapy (PDT) are three different methods proposed in the endoluminal treatment of lung cancers. The current article presents an overview of the specific indications and limits of each technique. These three methods were first proposed with palliative intent in inoperable patients with centrally located lung cancers. Now, the best indication is a curative intent in early stage lung cancers. Of the three, cryotherapy is the cheapest method. It induces cell necrosis in a 3-mm radius around the probe, and is suitable for treatment of superficial tumours. However, clinical trials are limited. In contrast, many clinical studies have confirmed the efficacy of PDT in treatment of superficial lung cancers. Brachytherapy can cure more aggressive tumours with deeper invasion into the bronchial wall. Unfortunately, no comparative studies have been published. Each of these methods induces a delayed tumour necrosis, and thus neither is indicated in the treatment of obstructive tumours with acute dyspnoea. In many situations, these methods should be complementary, particularly cryotherapy and brachytherapy or PDT and brachytherapy. The combination of these endoscopic methods with chemotherapy should be widely tested to promote the adjuvant role of the endoscopic methods in the treatment of lung cancers.