{{short description|Diminution or abatement of a disease over time, without formal treatment}} '''Spontaneous remission''', also called '''spontaneous healing''' or '''spontaneous regression''', is an unexpected improvement or cure from a disease that usually progresses. These terms are commonly used for unexpected transient or final improvements in cancer. Spontaneous remissions concern cancers of the haematopoietic system (blood cancer, e.g., leukemia), while spontaneous regressions concern palpable tumors; however, both terms are often used interchangeably.
==Definition== The spontaneous regression and remission from cancer was defined by Everson and Cole in their 1966 book as "the partial or complete disappearance of a malignant tumour in the absence of all treatment, or in the presence of therapy which is considered inadequate to exert significant influence on neoplastic disease."<ref name="Everson and Cole">Everson T., Cole W. (1968) ''Spontaneous Regression of Cancer'' Philadelphia, JB Saunder & Co (Book)</ref>
==Frequency of spontaneous regression in cancer== It has long been assumed that spontaneous regressions, let alone cures, from cancer are rare phenomena, and that some forms of cancer are more prone to unexpected courses (melanoma, neuroblastoma, lymphoma) than others (carcinoma). Frequency was estimated to be about 1 in 100,000 cancers;<ref name=Hobohm1>{{cite journal |pmid=11726133 |doi= 10.1007/s002620100216|year= 2001|last1= Hobohm|first1= U.|title= Fever and cancer in perspective|journal= Cancer Immunology, Immunotherapy |volume= 50|issue= 8|pages= 391–6|s2cid= 109998|pmc= 11032960}}</ref> however, this proportion might be an under- or an overestimate. For one, not all cases of spontaneous regression can be apprehended, either because the case was not well documented or the physician was not willing to publish, or simply because the patient ceased to attend a clinic any more. On the other hand, for the past 100 years almost all cancer patients have received some form of treatment, and the influence of that treatment cannot always be excluded.
It is likely that the frequency of spontaneous regression in small tumors has been drastically underrated. In a carefully designed study on mammography it was found that 22% of all breast cancer cases underwent spontaneous regression.<ref name=Zahl>{{cite journal |pmid=19029493 |doi=10.1001/archinte.168.21.2311|year=2008|last1=Zahl|first1=P. H.|title=The natural history of invasive breast cancers detected by screening mammography|journal=Archives of Internal Medicine|volume=168|issue=21|pages=2311–6|last2=Maehlen|first2=J.|last3=Welch|first3=H. G.}}</ref>
==Causes== Everson and Cole offered as explanation for spontaneous regression from cancer:{{blockquote|In many of the collected cases{{nbsp}}[...] it must be acknowledged that the factors or mechanisms responsible for spontaneous regression are obscure or unknown in the light of present knowledge. However, in some of the cases, available knowledge permits one to infer that hormonal influences probably were important.{{nbsp}}[...] In other cases, the protocols strongly suggest that an immune mechanism was responsible.<ref name="Everson and Cole"/>}}
Challis and Stam, even more at a loss, concluded in 1989, "In summary, we are left to conclude that, although a great number of interesting and unusual cases continue to be published annually, there is still little conclusive data that explains the occurrence of spontaneous regression."<ref name=Challis>{{cite journal |pmid=2206563 |doi= 10.3109/02841869009090048 |year= 1990 |title= The spontaneous regression of cancer. A review of cases from 1900 to 1987 |journal=Acta Oncologica |volume= 29 |issue=5 |pages=545–50 |last1=Challis |first1=G. B. |last2=Stam |first2= H. J.|doi-access=free }}</ref>
Apoptosis (programmed cell death) and angiogenesis (growth of new blood vessels) are sometimes discussed as possible causes of spontaneous regression. But both mechanisms need appropriate biochemical triggers and cannot initiate on their own. Indeed, in many cancer cells apoptosis is defective, and angiogenesis is activated, both of these effects being caused by mutations in cancer cells; cancer exists because both mechanisms are malfunctioning.<ref>Robert A. Weinberg (2007) ''The Biology of Cancer'', Garland Science</ref>
There are several case reports of spontaneous regressions from cancer occurring after a fever brought on by infection,<ref name=Hobohm1/><ref>{{cite journal |pmid=15700041 |pmc=2362074 |doi=10.1038/sj.bjc.6602386|year=2005 |last1=Hobohm |first1=U. |title=Fever therapy revisited |journal=British Journal of Cancer |volume=92 |issue=3 |pages=421–5 }}</ref> suggesting a possible causal connection. If this coincidence in time would be a causal connection, it should as well precipitate as prophylactic effect, i.e. feverish infections should lower the risk to develop cancer later. This could be confirmed by collecting epidemiological studies.<ref name=Hobohm>{{cite journal |pmid=18540826 |doi= 10.1615/critrevimmunol.v28.i2.10|year= 2008|last1= Hobohm|first1= U.|title= Pathogen-associated molecular pattern in cancer immunotherapy|journal= Critical Reviews in Immunology|volume= 28|issue= 2|pages= 95–107|last2= Stanford|first2= J. L.|last3= Grange|first3= J. M.}}</ref><ref name=Maletzki>{{cite journal |pmid= 23832140 |doi= 10.1007/s00262-013-1455-1 |url=http://www.fevertherapy.eu/references/maletzki-2013-cii-pamp.pdf|year= 2013 |last1= Maletzki |first1= C. |title= Mistletoe lectin has a shiga toxin-like structure and should be combined with other Toll-like receptor ligands in cancer therapy |journal= Cancer Immunology, Immunotherapy |volume= 62 |issue= 8 |pages= 1283–92 |last2= Linnebacher |first2= M. |last3= Savai |first3= R. |last4= Hobohm |first4= U. |pmc= 11028761 |s2cid= 26031460 }}</ref>
==Reviews== *Rohdenburg (1918) summarized 185 spontaneous regressions<ref>{{cite journal |last1=Rohdenburg |first1=G. L. |title=Fluctuations in the Growth Energy of Malignant Tumors in Man, with Especial Reference to Spontaneous Recession |journal=The Journal of Cancer Research |date=1 April 1918 |volume=3 |issue=2 |pages=193–225 |doi=10.1158/jcr.1918.193 |language=en|doi-broken-date=12 July 2025 }}</ref> *Fauvet reported 202 cases between 1960 and 1964<ref>{{cite journal |pmid=14157391|year=1964|last1=Fauvet |first1=J.|title=Spontaneous Cancer Cures and Regressions|journal=La Revue du Praticien|volume=14|pages=2177–80|last2=Roujeau |first2=J. |last3=Piet |first3=R.}}</ref> *Boyd reported 98 cases in 1966<ref>Boyd W: ''The spontaneous regression of cancer.'' Charles Thomas, Publ., Springfield Ill. 1966 (Book)</ref> *Everson and Cole described 176 cases between 1900 and 1960<ref name="Everson and Cole"/><ref>{{cite journal |pmid=799760|year=1976|last1=Cole|first1=W. H.|title=Spontaneous regression of cancer and the importance of finding its cause|journal=National Cancer Institute Monograph|volume=44|pages=5–9}}</ref> *Challis summarized 741 cases between 1900 and 1987<ref name="Challis"/> *O'Regan Brendan, Carlyle Hirschberg collected over 3,500 references from the medical literature<ref>{{Cite book |title=Spontaneous Remission. An Annotated Bibliography |last1=O'Regan |first1=Brendan |last2=Hirschberg |first2=Carlyle |publisher=Institute of Noetic Sciences |year=1993 |isbn=978-0-943951-17-1 |location=Sausalito, California }}</ref> *Hobohm, in a meta-analysis, investigated about 1000 cases<ref name="Hobohm1"/> *Turner, in a qualitative research study, conducted interviews with 20 patients with spontaneous remissions<ref>{{Cite thesis |url=http://escholarship.org/uc/item/3px3w4g9 |title=Spontaneous Remission of Cancer: Theories from Healers, Physicians, and Cancer Survivors |last=Turner |first=Kelly Ann |publisher=UC Berkeley Electronic Theses and Dissertations |year=2010 |location=Berkeley }}</ref> * ''Surviving Against All Odds'' - re sole survivor in "''a gamma interferon study''"<ref>{{cite magazine |magazine=Newsweek |url=https://www.newsweek.com/surviving-against-all-odds-180512 |title=Surviving Against All Odds |author=Geoggrey Cowley |date=March 13, 1995 |page=63}}</ref><ref>{{cite book |title=Remarkable Recovery |isbn=9781573225304 |publisher=Riverhead Books |author1=Caryle Hirshberg |author2=Marc Ian Barasch|year=1996 }}</ref>
==References== {{Reflist}}
==Further reading== * Uwe Hobohm: ''Healing Heat'', 2014, {{ISBN|978-0-557-02885-6}} * Uwe Hobohm: ''Harnessing Infection to Fight Cancer'', American Scientist January–February 2009 [http://www.americanscientist.org] * [https://web.archive.org/web/20201201062713/https://www.discovermagazine.com/health/the-body-can-beat-terminal-cancer-sometimes The Body Can Beat Terminal Cancer — Sometimes.] ''Discover Magazine'', September 2007
==External links== * [http://www.fevertherapy.eu/introduction/ Spontaneous remissions and an immunological explanation]
{{DEFAULTSORT:Spontaneous Remission}} Category:Medical terminology Category:Oncology