NGPDT is mainly a trademark for companies doing more or less regular PDT treatments at high cost. Although tey claim to use a different substance from regular PDT, they do not specify how it is different. This is a somewhat strange claim since there are several different substances being used in the 'regular' PDT protocols. Photodynamic therapy has been widely used in Russia for quite long and is usen in the UK for varios cancerous and precancerous conditions. The PDT substances, which are mostly chlophyll derivatives are constantly reseached and developed in various countries. Check the journal PDPDT (Elsevier). Also check www.laserhelsinki.fi where you can find several abstracts from top specialists about different applications of PDT. On my page there are also some abstracts available.
In general, besides the usual issues of being absorbed &/or retained differentially in the cancer cells, regular PDT has tended to be of limited usefulness by the activating light not being able to penetrate very far. There has been research on other chemicals that can respond to deeper-penetrating near-infrared light (IR700, see http://www.nature.com/nm/journal/v17/n12/pdf/nm.2554.pdf#firstFrame ).
The branded product named NGPTD (next generation PDT) (ngpdt.org in the province outside Hong Kong but also tcngpdt.com in Beijing) claims effectiveness for even lung cancer. As far as I can tell, I don't think they rely on specific deep-penetrating wavelengths; they'll poke light-conveying probes/tubes to specific areas to try to better penetrate particular tumor masses.
The problem from Western medicine's point of view is that they don't have peer-reviewed published research in order to have a valid assessment of odds of effectiveness, PFS, recurrence, repeatability/resistance, side effects, biochemical mechanism of action (e.g., how differential absorption/retention is achieved, which wavelengths of light matter), etc. At a cost of something like USA $40k (x2 since I think they encourage repeat a few weeks later if it seems to help) it's problematic being expensive but not publically scientifically proven even though there are clearly examples of effectiveness. As far as I know, they are not pursuing the USA market (I think they feel their hands are full growing their business in China and Asian countries with easier regulations), so clinical trial data is not available, but they do have a limited trial underway in Australia which might start to produce the kind of research support the profession requires.
They have done their own research for themselves and disclosed a little of it on their web site, but as far as I can tell they have not offered full disclosure like we are accustomed to seeing and have not yet pursued proper peer review. Their focus seems to be on building their proprietary business in China. At ASCO 2013 there was an e-Abstract (an abstract without poster presentation nor completed research paper) on the subject ( http://meetinglibrary.asco.org/content/113379-132 ), and along with the Australian trial they appear to be taking small steps toward more reliable peer-reviewed data beyond their original "just trust us because China allows us to use our proprietary approach and we have some nice testimonials on YouTube."
Although their lack of peer-reviewed published data invites skepticism by Western medical standards, [*if* I understood & recall correctly] their marketing tries to cast this as just needing to avoid attracting competition as they try to build their branded treatment business throughout China & certain other locations. (My impression is that they don't put much faith in patent protection for what they are doing. I don't know if their photodynamic compound is their own creation or just bought under a country-specific exclusive contract from the producer.)
Bottom line: NGPDT's YouTube testimonials and disclosed summary data seem to at least show it is effective for at least some tumors in some patients, at least initially. But from a Western medicine point of view there are still many unanswered questions about the % odds of benefit, amount of benefit, which specific types of cancer and attributes have good odds of benefit, types and patterns of resistance/re-emergence, mechanisms of differential absorption/retention & action, etc. I hope to see their research make progress along these lines.
There are a few of these systems around. Regarding tissue penetration, the use of chromophores which respond to longer wavelengths allows correspondingly deeper tissues to be reached. The most interesting chromophores are derived from deep water marine algae - it is only the longer wavelengths that reach these organisms.
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