Zaid Hamdoon, Waseem Jerjes, Jocelyn Brookes, Tahwinder Upile, Rishi Bhandari, Colin Hopper, Charles A. Mosse, Sorcha Mackay, Simon Morley, Farai Nhembe, and Priya Shah
Department of Radiology, University College London Hospital, London, UKIntroduction:Interstitialphotodynamictherapyremainsan attractive remedial option in minimally invasivesurgery. Our aim in this prospective study was to evaluatethe outcome following ultrasound-guided iPDT of deep-seated pathologies. Patients’ reports on quality of life withclinicalandradiologicalevaluationwerethemainendpointparameters used to assess the outcome.Materials and Methods: Sixty-eight patients werereferredtotheUCLHHeadandNeckCentre fortreatmentof various deep-seated pathologies involving the head andneckregion,upperandlowerlimbs.Allpatientsunderwentinterstitial photodynamic therapy under general anaes-thesia, using 0.15mg/kg mTHPC as the photosensitisingagent.Followingtreatment,patientswerefollowed-upforamean of 7 months.Results: All three patients who presented with visualproblemsreportedimprovementaftertreatment.Also,14/17patients reported improvement of breathing. Improvementof swallowing was reported by 25/30 patients; while speak-ing improvement was evident in 16/22 patients and 33/40reported reduction in the disfigurement caused by theirpathology. All five patients with impeded limb functionreported some degree of improvement. Clinical assessmentshowed that half of the patients had ‘good response’ to thetreatmentandathirdreported‘moderateresponse’withtwopatients being free of disease. Radiological assessmentcomparingimaging6-weekpost-PDTtothebaselineshowedstable pathology with no change in size in 13 patients,minimal response in 18 patients, moderate response in23 patients and significant response in 11 patients.Conclusion: This study on 68 patients with deep-seatedpathologies undergoing interstitial photodynamic therapyprovided evidence that PDT can be the fourth modalityin the management of tissue disease. Lasers Surg. Med.41:612–621, 2009. 2009 Wiley-Liss, Inc.Key words: photodynamic therapy; ultrasound; headand neck; cancer treatment; tumour; vascular malforma-tion; hamartoma; interstitialINTRODUCTIONPhotodynamic therapy (PDT) remains an attractiveremedial option in oncology. In principle, light applicationto the target tissue leads to a non-thermal photochemicalreaction; this is usually initiated some hours following theadministrationofthephotosensitiser andleadstoselectivedamage to the target tissue. The efficacy of the treatmentdepends on the type and the concentration of the photo-sensitiser, light dose, fluence rate, the availability ofoxygen and cellular localisation. Several photosensitisersare currently being tested for better specificity of targettissue [1–3].Two generations of photosensitisers are currently beingused in oncological practice. Profimer sodium (Photofrin-first generation) is commonly used in Barrett’s high-gradedysplasia, cervical, gastric, oesophageal, endobronchialandpapillarybladdercancers.While5-aminolevulinicacid(5-ALA), a natural heme precursor, has been successfullyapplied in basal cell carcinoma, actinic keratosis and oraldysplasia. mTHPC (Foscan) a much more potent secondgeneration photosensitiser for cancer treatment, whencompared to Photofrin and ALA, is commonly used in headand neck cancer. Third generation photosensitisers (tinethyl etiopurpurin, mono