 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
Medical Forum / Diseases and Disorders / Cancer / May 2005Positive liver cancer trial results; pancreatic cancer trial later
I thought I'd let people know about a new form of brachytherapy - the direct injection into tumours of porous silicon doped with the radionuclide phosphorus 32. The radionuclide is held in place by the silicon and kills the surrounding cancer cells. The porous silicon dissolves over time into harmless silicic acid, so there is no insoluble matter left in the liver forever. The treatment has been tested on primary liver cancer tumours in a small trial involving eight patients at Singapore General Hospital, and the results look very promising. The only available information I know of is in the form of announcements by the company that owns the technology. To declare my interest, I am a shareholder of the company, but I'm posting here only to let those with an interest in cancer know about the treatment. Results for the first four patients, October 2004 http://www.psivida.com.au/investor/docs/ASXRelease_BrachySil_Interim_Trial_R esults_Oct04.pdf Results for the other four patients, February 2005 http://www.psivida.com/news/download/ASX/ASXRelease_BrachySil%20trial%20resu lts_150205.pdf This treatment can potentially be used to treat any solid tumour that can be reached with a fine gauge needle. A trial for pancreatic cancer is expected later this year, mainly because there are so few options for this cancer. http://www.psivida.com/news/download/ASX/asx_brachysil_080405.pdf David > I thought I'd let people know about a new form of brachytherapy - the direct > injection into tumours of porous silicon doped with the radionuclide [quoted text clipped - 22 lines] > > David UK news is calling it a device. Yet the 4th pdf is calling it a treatment. In any event, way too premature to be announcing it here and especially alt.support.cancer. Your cohorts are too small, not enough details, and not enough time has passed. Where's the information as to the 12 Singapore patients from last June? J > UK news is calling it a device. The company has had indications that it will be registered as a device, at least in Asia and Europe. > Yet the 4th pdf is calling it a treatment. I don't know if 'treatment' has a precise meaning in such a context. If so, my guess is that it was used loosely in the announcement. > In any event, way too premature to be announcing it here and especially > alt.support.cancer. Sorry. I wondered if it was appropriate, but there's quite a few cross-postings to these groups, and I thought that some people might like to know, so they can keep an eye on it. > Your cohorts are too small, not enough details, and not enough time has passed. I agree that more trials are needed. However, given the simplicity of the treatment, the results so far look very promising. The effect of radionuclides is well known. You just know that if you put a beta emitter such as P32 close to human cells, it is going to kill them, so there can be little doubt that this treatment is going to cause regression of tumours. A greater concern is the possibility of leakage of the P32 to the healthy liver tissue or the rest of the body. Apparently, leakage is the reason that other forms of brachytherapy need to use inferior radionuclides such as yttrium 90 and iodine 125. In the case of porous silicon, the phosphorus is well-bound to the silicon, so leakage can only occur if entire particles of the porous silicon can move elsewhere. I don't know how likely that is, but it is certainly encouraging that it hasn't happened in any of these patients. There was a briefing on the 18th of March this year at which the company said that all eight patients were still alive, but I don't know how likely that was anyway if they hadn't received the treatment or had received a different treatment. > Where's the information as to the 12 Singapore patients from last June? I don't know where you read that there were 12 patients. There was an announcement on 15 June 2004 that the first two patients had received the treatment, and I believe they were the first two of the eight for whom we have the results. David > > Where's the information as to the 12 Singapore patients from last June? > > I don't know where you read that there were 12 patients. There was an > announcement on 15 June 2004 that the first two patients had received the > treatment, and I believe they were the first two of the eight for whom we > have the results. I'll guess that you've come across the article at http://news.bbc.co.uk/1/hi/sci/tech/3812987.stm, or something similar. I don't remember if it was ever announced that there would be 12 patients, but I'm sure that there weren't. The reporting of this treatment has been rather poor. That article confuses two completely different kinds of treatment that can be delivered by porous silicon - drugs and radionuclides - and claims wrongly at the beginning that BrachySil is a drug treatment and that that's what the Singapore patients received. Drug delivery by porous silicon is actually the company's focus, but it's not as far advanced as the radionuclide. The article at http://www.abc.net.au/news/newsitems/200410/s1225290.htm is even worse. It talks about silicon "chips", as though the silicon particles are some kind of space age electronic devices, which is utter nonsense. The "chips" description might not have originated there, but, wherever it started, it soon appeared all over the place. It's all good publicity I guess, but I'd rather they got it right. David >> UK news is calling it a device. > [quoted text clipped - 51 lines] > > David Local treatments for metastatic cancers are just plain silly > Local treatments for metastatic cancers are just plain silly I'm not sure what you are referring to. The disease treated in the BrachySil trial was primary liver cancer, and I imagine that the trial coming up is for primary pancreatic cancer. However, such a treatment would be worthwhile for secondary tumours as well if those tumours are the most life-threatening the patient has. BTW, the current data from the BrachySil trial will be presented at the European Society for Therapeutic and Radiation Oncology Conference in Budapest on 5th May. David P.S. I have no medical training, so let me know if I say anything plain silly. > BTW, the current data from the BrachySil trial will be presented at the > European Society for Therapeutic and Radiation Oncology Conference in > Budapest on 5th May. This is the abstract from the conference: Proof of concept of novel 32P Brachytherapy device in hepatocellular carcinoma (HCC) in man A.Goh(1), R. Lo(1), T.N. Lau(1), A.Y. Chung(1), D. Ng(1), W.K. Yu(1), S. Loong(2), M. Chng(1), S. Somanesan(1), B.C. Lim(3), S. Connor(4), P.K.Chow(1) 1 Singapore General Hospital 2 National Cancer Center Singapore 3 pSiOncology Pte Singapore 4 pSiMedica Ltd, Malvern UK Hepatocellular carcinoma (HCC) is the 4th most important malignancy worldwide. The vast majority of HCC are however unresectable and therapy in this group remains poorly efficacious and the prognosis dismal. Interstitial brachytherapy of solid hepatic tumours such as HCC is potentially advantageous but the requisite for widespread clinical application is a delivery vehicle with properties that can reliably confine the radiation source to the implantation site. A novel implantable medical device comprising 32P and proprietary porous silicon, BioSilicon(T) (BrachySil(T)) was investigated in eight patients with non-resectable HCC in an open label single dose trial. Patients received single intratumoural implantations introduced percutaneously under sonographic / imaging guidance into a maximum of three tumours (4 MBq/ml tumour). The procedure was very well tolerated by all patients. Follow-up assessment at close intervals up to 12 weeks demonstrated no significant product-related adverse clinical or haematological effects. Examination of blood parameters suggested no extrahepatic leakage of radioactivity from the device implanted. Although the primary objective of the study was to determine safety and tolerability, the anti-cancer activity of BrachySil(T) was confirmed with CT evaluations showing significant tumour regression at all implantation sites. The study establishes proof of principle for BrachySil(T) in the treatment HCC as a tolerable and effective brachytherapy agent. David |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2008 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.