Editing Experimental cancer treatment (section)

==Radiation therapies==

===Photodynamic therapy===
[[Photodynamic therapy]] (PDT) is generally a non-invasive treatment using a combination of light and a photosensitive drug, such as 5-ALA, Foscan, Metvix, [[padeliporfin]] (Tookad, WST09, WST11), Photofrin, or [[Verteporfin|Visudyne]]. The drug is triggered by light of a specific wavelength.

===Hyperthermiatic therapy===
{{Further|Hyperthermia therapy}}

Localized and whole-body application of heat has been proposed as a technique for the treatment of malignant tumours. Intense heating will cause [[denaturation (biochemistry)|denaturation]] and coagulation of [[cell (biology)|cellular]] [[protein]]s, rapidly killing cells within a tumour.

More prolonged moderate heating to temperatures just a few degrees above normal (39.5&nbsp;°C) can cause more subtle changes. A mild heat treatment combined with other stresses can cause cell death by [[apoptosis]]. There are many biochemical consequences to the [[heat shock protein|heat shock response]] within the cell, including slowed cell division and increased sensitivity to ionizing [[radiation therapy]]. The purpose of overheating the tumor cells is to create a lack of oxygen so that the heated cells become overacidified, which leads to a lack of nutrients in the tumor. This in turn disrupts the metabolism of the cells so that cell death (apoptosis) can set in. In certain cases chemotherapy or radiation that has previously not had any effect can be made effective. Hyperthermia alters the cell walls by means of so-called heat shock proteins. The cancer cells then react very much more effectively to the cytostatics and radiation. If hyperthermia is used conscientiously it has no serious side effects.<ref>Dr med Peter Wolf, 2008, Innovations in biological cancer therapy, a guide for patients and their relatives, p 31-32</ref>

There are many techniques by which heat may be delivered. Some of the most common involve the use of focused [[ultrasound]] (FUS or [[HIFU]]), [[microwave]] heating, [[induction heating]], [[magnetic hyperthermia]], and direct application of heat through the use of heated saline pumped through catheters. Experiments with carbon nanotubes that selectively bind to cancer cells have been performed. Lasers are then used that pass harmlessly through the body, but heat the nanotubes, causing the death of the cancer cells. Similar results have also been achieved with other types of [[nanoparticle]]s, including gold-coated nanoshells and nanorods that exhibit certain degrees of 'tunability' of the absorption properties of the nanoparticles to the wavelength of light for irradiation. The success of this approach to cancer treatment rests on the existence of an 'optical window' in which biological tissue (i.e., healthy cells) are completely transparent at the wavelength of the laser light, while nanoparticles are highly absorbing at the same wavelength. Such a 'window' exists in the so-called near-infrared region of the electromagnetic spectrum. In this way, the laser light can pass through the system without harming healthy tissue, and only diseased cells, where the nanoparticles reside, get hot and are killed.

[[Magnetic Hyperthermia]] makes use of magnetic nanoparticles, which can be injected into tumours and then generate heat when subjected to an alternating magnetic field.<ref>[http://www.physics.org/featuredetail.asp?id=44 Hyperthermia - Cancer therapy hots up] on physics.org</ref>

One of the challenges in thermal therapy is delivering the appropriate amount of heat to the correct part of the patient's body. A great deal of current research focuses on precisely positioning heat delivery devices (catheters, microwave, and ultrasound applicators, etc.) using ultrasound or [[magnetic resonance imaging]], as well as of developing new types of nanoparticles that make them particularly efficient absorbers while offering little or no concerns about toxicity to the circulation system. Clinicians also hope to use advanced imaging techniques to monitor heat treatments in real time—heat-induced changes in [[biological tissue|tissue]] are sometimes perceptible using these imaging instruments. In [[magnetic hyperthermia]] or magnetic fluid hyperthermia method, it will be easier to control temperature distribution by controlling the velocity of [[ferrofluid]] injection and size of [[magnetic nanoparticles]].<ref>{{cite journal | vauthors = Javidi M, Heydari M, Attar MM, Haghpanahi M, Karimi A, Navidbakhsh M, Amanpour S | title = Cylindrical agar gel with fluid flow subjected to an alternating magnetic field during hyperthermia | journal = International Journal of Hyperthermia | volume = 31 | issue = 1 | pages = 33–9 | date = February 2015 | pmid = 25523967 | doi = 10.3109/02656736.2014.988661 | s2cid = 881157 | doi-access = free }}</ref><ref>{{cite journal | vauthors = Javidi M, Heydari M, Karimi A, Haghpanahi M, Navidbakhsh M, Razmkon A | title = Evaluation of the effects of injection velocity and different gel concentrations on nanoparticles in hyperthermia therapy | journal = Journal of Biomedical Physics & Engineering | volume = 4 | issue = 4 | pages = 151–62 | date = December 2014 | pmid = 25599061 | pmc = 4289522 }}</ref><ref>{{cite journal |doi=10.1142/S0219519415500888 | volume=15 | issue=5 | journal=[[Journal of Mechanics in Medicine and Biology]] | pages=1550088| year=2015 | last1=Heydari | first1=Morteza | last2=Javidi | first2=Mehrdad | last3=Attar | first3=Mohammad Mahdi | last4=Karimi | first4=Alireza | last5=Navidbakhsh | first5=Mahdi | last6=Haghpanahi | first6=Mohammad | last7=Amanpour | first7=Saeid | title=Magnetic Fluid Hyperthermia in a Cylindrical Gel Contains Water Flow }}</ref>

===Noninvasive cancer heat treatment===
Heat treatment involves using radio waves to heat up tiny metals that are implanted in cancerous tissue. [[Gold nanoparticle]]s or [[carbon nanotube]]s are the most likely candidate. Promising preclinical trials have been conducted,<ref name="Studies on using radio waves against cancer are advancing">
{{cite news |title=Research on local man's cancer treatment idea shows it has promise
| author = David Templeton |newspaper=Pittsburgh Post-Gazette |date=18 January 2007 |access-date=4 November 2007 |url=http://www.post-gazette.com/pg/07018/754702-114.stm}}</ref><ref>{{cite journal | vauthors = Gannon CJ, Cherukuri P, Yakobson BI, Cognet L, Kanzius JS, Kittrell C, Weisman RB, Pasquali M, Schmidt HK, Smalley RE, Curley SA | title = Carbon nanotube-enhanced thermal destruction of cancer cells in a noninvasive radiofrequency field | journal = Cancer | volume = 110 | issue = 12 | pages = 2654–65 | date = December 2007 | pmid = 17960610 | doi = 10.1002/cncr.23155 | s2cid = 15680068 }}</ref> although clinical trials may not be held for another few years.<ref name="The cure to cancer could be in your radio!">{{cite news |year=2007 |title=The cure to cancer could be in your radio! |publisher=Winknews.com |access-date=1 November 2007 |url=http://www.winknews.com/features/health/10949561.html |archive-date=2 November 2007 |archive-url=https://web.archive.org/web/20071102225618/http://www.winknews.com/features/health/10949561.html |url-status=dead }}</ref>

Another method that is entirely non-invasive referred to as [[Tumor Treating Fields]] has already reached clinical trial stage in many countries. The concept applies an [[electric field]] through a tumour region using electrodes external to the body. Successful trials have shown the process effectiveness to be greater than chemotherapy and there are no side-effects and only negligible time spent away from normal daily activities.<ref>{{cite journal | vauthors = Pless M, Weinberg U | title = Tumor treating fields: concept, evidence and future | journal = Expert Opinion on Investigational Drugs | volume = 20 | issue = 8 | pages = 1099–106 | date = August 2011 | pmid = 21548832 | doi = 10.1517/13543784.2011.583236 | s2cid = 903933 }}</ref><ref>{{Cite web |year=2012 |title=Tumour Treating Fields explained | publisher= ted.com |access-date=31 January 2012 |url=http://www.ted.com/talks/bill_doyle_treating_cancer_with_electric_fields.html}}</ref> This treatment is still in very early development stages for many types of cancer.

[[High-intensity focused ultrasound]] (HIFU) is still in investigatory phases in many places around the world.<ref name="Steven Mo, Constantin-C Coussios, Len Seymour & Robert Carlisle 2012 1525">{{cite journal | vauthors = Mo S, Coussios CC, Seymour L, Carlisle R | title = Ultrasound-enhanced drug delivery for cancer | journal = Expert Opinion on Drug Delivery | volume = 9 | issue = 12 | pages = 1525–38 | date = December 2012 | pmid = 23121385 | doi = 10.1517/17425247.2012.739603 | s2cid = 31178343 }}</ref> In China it has CFDA approval and over 180 treatment centres have been established in China, Hong Kong, and Korea. HIFU has been successfully used to treat cancer to destroy tumours of the bone, brain, breast, liver, pancreas, rectum, kidney, testes, and prostate. Several thousand patients have been treated with various types of tumours. HIFU has CE approval for palliative care for bone metastasis. Experimentally, palliative care has been provided for cases of advanced pancreatic cancer. High-energy therapeutic ultrasound could increase higher-density anti-cancer drug load and nanomedicines to target tumor sites by 20x fold higher than traditional target cancer therapy.<ref>{{cite journal | vauthors = Mo S, Carlisle R, Laga R, Myers R, Graham S, Cawood R, Ulbrich K, Seymour L, Coussios CC | title = Increasing the density of nanomedicines improves their ultrasound-mediated delivery to tumours | journal = Journal of Controlled Release | volume = 210 | issue = 10 | pages = 10–8 | date = July 2015 | pmid = 25975831 | doi = 10.1016/j.jconrel.2015.05.265 | doi-access = free }}</ref>