Kangri cancer is a type of
squamous-cell carcinoma
Squamous-cell carcinomas (SCCs), also known as epidermoid carcinomas, comprise a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on th ...
of the
skin
Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation.
Other cuticle, animal coverings, such as the arthropod exoskeleton, have diffe ...
. It is found only in
Kashmir in the northwest of the
Indian subcontinent
The Indian subcontinent is a physiographical region in Southern Asia. It is situated on the Indian Plate, projecting southwards into the Indian Ocean from the Himalayas. Geopolitically, it includes the countries of Bangladesh, Bhutan, India ...
. It occurs on the lower
abdomen
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the tors ...
and inner
thigh
In human anatomy, the thigh is the area between the hip ( pelvis) and the knee. Anatomically, it is part of the lower limb.
The single bone in the thigh is called the femur. This bone is very thick and strong (due to the high proportion of ...
s and is due to the use of a
kanger, a ceramic pot covered with wicker-work, carried as a source of warmth during cold weather. One of the earliest records of the condition was made in 1881 by surgeons at the Kashmir Mission Hospital and its cause was recognized in the early 20th century by
Arthur Neve.
[Neve A (1900) Indian med. Gaz. 35, 81]
Despite current knowledge of the cause of this condition, cases are still being reported.
Other conditions associated with prolonged use of kangri in this fashion include
erythema ab igne, a reticulate hypermelanosis with
erythema
Erythema (from the Greek , meaning red) is redness of the skin or mucous membranes, caused by hyperemia (increased blood flow) in superficial capillaries. It occurs with any skin injury, infection, or inflammation. Examples of erythema not asso ...
.
Signs and symptoms
Most cases (80%) of
squamous cell carcinoma
Squamous-cell carcinomas (SCCs), also known as epidermoid carcinomas, comprise a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on th ...
attributed to ultraviolet radiation present in areas of the skin that are usually more exposed to sunlight (e.g., head, face, neck).
Although a particular form of squamous cell carcinoma, Kangri cancer is more often associated with the abdomen, thigh, and leg regions due to the usage and positioning of kangri pots, which come in close contact with these anatomical features.
Over time, the use of kangri pots to keep warm results in
erythema ab igne, a precancerous keratotic growth that "take the shape of superficial, serpegenous, reticular blackish brown colored lesions."
Eventually, the cells at the lesion site become more irregular in shape and form; the lesions ulcerate and may become itchy and bloody. The resulting irregular growth is the presentation of kangri cancer.
Risk factors
Use of the kangri pot is the principal cause of kangri cancer. The pot holds hot wood and charcoal, and is put in direct contact with the skin of the abdomen and the thigh areas as a way to keep warm during winter in northern India.
Elements that are believed to contribute to the development of kangri cancer are heat, burning wood particles, smoke, soot, and tar of burnt
chinar
''Platanus orientalis'', the Old World sycamore or Oriental plane, is a large, deciduous tree of the Platanaceae family, growing to or more, and known for its longevity and spreading crown. In autumn its deep green leaves may change to blood ...
leaves.
In one study, researchers found that kangri cancer patients had a history of using a kangri for 5–6 hours a day, 3–4 months a year.
Genetics
Beyond the behavioral risk factor of prolonged usage of kangri pots, researchers have begun to look at genetic mutations that may make some people more predisposed to develop kangri cancer.
* In one study, people with kangri cancer were found to be approximately twice as likely as a control group to have a mutation in the
TP53 gene (codon 72
polymorphism
Polymorphism, polymorphic, polymorph, polymorphous, or polymorphy may refer to:
Computing
* Polymorphism (computer science), the ability in programming to present the same programming interface for differing underlying forms
* Ad hoc polymorphis ...
). Patients with higher grade tumors exhibited more
proline amino acid
Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha ...
mutations at this site.
* Another study confirmed the association of kangri Cancer and TP53, finding substitutions and insertions in 40% of the kangri cancer patients studied. The researchers observed a significant correlation with mutation status and age as well as with the presence of affected lymph nodes in patients. TP53 may, in the future, serve as "potential molecular marker and prognostic tool" for kangri cancer. Furthermore,
PTEN mutations were found in two of thirty patients studied; though due to the small sample size, no useful conclusions could be postulated.
* Two polymorphisms of the
HSP70
The 70 kilodalton heat shock proteins (Hsp70s or DnaK) are a family of conserved ubiquitously expressed heat shock proteins. Proteins with similar structure exist in virtually all living organisms. Intracellularly localized Hsp70s are an importa ...
gene were discovered to be correlated with poor
prognosis
Prognosis (Greek: πρόγνωσις "fore-knowing, foreseeing") is a medical term for predicting the likely or expected development of a disease, including whether the signs and symptoms will improve or worsen (and how quickly) or remain stabl ...
in cases of kangri cancer; the “Hsp70-2 A/G or G/G and Hsp70homC/C genotypes” could potentially be utilized to measure risk of kangri cancer development as well as to predict prognosis.
Treatment
Surgery
In the treatment of kangri cancer, surgery is, most often, the first-line course of action to remove the primary tumor.
Radiotherapy
External beam radiotherapy
External beam radiotherapy (EBRT) is the most common form of radiotherapy (radiation therapy). The patient sits or lies on a couch and an external source of ionizing radiation is pointed at a particular part of the body. In contrast to brachyt ...
has been used in one person to prevent the relapse and growth of tumor metastases to the head and neck regions. The prophylactic applications of radiation have been noted as "encouraging" in this one case, reducing some tumors and eliminating others.
Another study with a couple of the same authors found that radiotherapy after surgery helped with the reduction and cure of head and neck tumors in additional cases. The researchers suggest that external beam radiotherapy should be part of the treatment course for patients who have or at risk of developing tumors in the head and neck areas.
Prognosis
A research article from 1923 noted that the average
life expectancy
Life expectancy is a statistical measure of the average time an organism is expected to live, based on the year of its birth, current age, and other demographic factors like sex. The most commonly used measure is life expectancy at birth ...
of those with kangri cancer was about fifteen months, though there have been records of people dying within one year and living for more than twenty years with kangri cancer.
Updated
life expectancy
Life expectancy is a statistical measure of the average time an organism is expected to live, based on the year of its birth, current age, and other demographic factors like sex. The most commonly used measure is life expectancy at birth ...
is not found in more recent scientific publications.
However, in 2013, it was noted that the progression from
erythema ab igne to
squamous cell carcinoma
Squamous-cell carcinomas (SCCs), also known as epidermoid carcinomas, comprise a number of different types of cancer that begin in squamous cells. These cells form on the surface of the skin, on the lining of hollow organs in the body, and on th ...
was between one and two decades.
It has been reported that about one-third to one-half of patients with kangri cancer show
metastasis
Metastasis is a pathogenic agent's spread from an initial or primary site to a different or secondary site within the host's body; the term is typically used when referring to metastasis by a cancerous tumor. The newly pathological sites, then, ...
to local
lymph nodes
A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that incl ...
.
Epidemiology
The first case of kangri cancer was reportedly recognized in 1819.
The
incidence of kangri cancer is higher for those over age 50.
There is no definitive predominance of kangri cancer in either males or females. Some studies may point to higher prevalence in males while others observed higher prevalence in females.
In scientific literature, kangri cancer has only been attributed to the
Kashmir region due to the traditional use of kangri pots. Kangri cancer is limited to this population, and thus, relatively little is known still, and there is much to be studied about the condition.
In 2017, a local Kashmir media outlet, ''The Kashmir Reader,'' reported that researchers and health care providers are optimistic about the reduced incidence of kangri cancer, citing the rise of thermal clothing and electric heating sources that are now used in place of kangri pots to keep warm.
See also
*
List of cutaneous conditions
Many skin conditions affect the human integumentary system—the organ system covering the entire surface of the body and composed of skin, hair, nails, and related muscle and glands. The major function of this system is as a barrier agai ...
References
External links
'Kangri cancer' cases declining in Kashmir Valley (The Indian Express)
{{Radiation-related disorders
Skin conditions resulting from physical factors
Diseases and disorders in India