Sunday, October 9, 2005
The current Lancet has a review of cholangiocarcinoma, unfortunately an over-represented disease for us in palliative care. I personally found it very helpful. The news isn't good: intrahepatic cholangiocarcinoma is becoming more common & mortality hasn't improved in the last 30 years. The last few sections of the review cover palliative therapies** including the role of biliary stenting & photodynamic therapy which I've been reading about for a bit but have yet to see used although, per this reviewer, it sounds quite helpful:
In this novel treatment, the photosensitiser sodium porfimer (which localises to mitochondria) is given intravenously and localises preferentially in tumour tissue over 24–48 h. This process is followed by endoscopic direct illumination of the tumour bed with a specific wavelength of light resulting in the activation of the porfimer, generating oxygen free radicals and leading to ischaemic cancer cell death. This technique has been shown to regress carcinomas of the skin, lungs, pharynx, oesophagus, and stomach. The tumoricidal tissue penetration achieved is a depth of 4 mm and hence it is regarded as a palliative option. The estimated time to tumour progression is about 6 months, meaning that photodynamic therapy is needed twice yearly.
In a prospective study, 39 patients with Bismuth III/IV cholangiocarcinomas were randomised to treatment with either biliary stenting plus photodynamic therapy or stenting alone. The photodynamic therapy group had higher median survival (493 days vs 98 days), less cholestasis, better quality of life scores, and better stabilisation of Karnofsky performance status than did the stenting group. The improved survival was probably secondary to relief of obstruction rather than a reduction in tumour mass. Further studies are needed, especially of photodynamic therapy in combination with radiation or chemotherapy, or both.
**"Palliative" in this article means all non-curative interventions. The authors unfortunately perpetuate the confusion surrounding the use of "palliative" by including both life-prolonging but non-curative interventions & interventions that are only intended to improve quality of life. By this logic ACE-inhibitors for heart failure & insulin for diabetes are palliative therapies.