| Popis: |
The diagnosis and treatment of pancreaticobiliary malignancy is of major interest to our group. Building on prior work, we undertook a phase I study of verteporfin photodynamic therapy in patients with locally advanced, unresectable, pancreatic cancer. We also initiated an optical diagnostic study using elastic scattering spectroscopy (ESS) of the normal-appearing periampullary duodenal mucosa in vivo to investigate the hypothesis of a field effect in pancreaticobiliary malignancy. In a phase I dose escalation study, patients were treated with interstitial verteporfin PDT via a single fibre, to determine its general safety profile and the optimum treatment parameters needed to achieve effective and safe necrosis of tumour, With increasing light doses, there was a linear increase in the extent of tumour necrosis around the fibre, without serious adverse events. Follow-on studies using multiple fibres are planned. In 30 patients with benign or malignant pancreaticobiliary disease undergoing clinically-indicated endoscopy, ESS spectra were collected from the normal-appearing duodenum and antrum and a diagnostic algorithm generated by principle component and linear discriminant analysis. Pooled data from duodenal sites distal to the ampulla gave a sensitivity of 86% and a specificity of 72% (82% AUC) for the detection of malignancy, whereas those from the periampullary region had a sensitivity of 77% and a specificity of 61% (72% AUC); antral measurements were not able to discriminate with such accuracy. These early results suggest that ESS of the duodenal mucosa could represent a novel minimally invasive diagnostic test for pancreaticobiliary malignancy. |
