Chimney sweeps' cancer, also called soot wart or scrotal cancer, is a
squamous cell carcinoma
Squamous-cell carcinoma (SCC), also known as epidermoid carcinoma, comprises 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 the ...
of the
scrotum
In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin ...
. It has the distinction of being the first reported form of
occupational cancer, and was initially identified by
Percivall Pott in 1775. It was initially noticed as being prevalent amongst
chimney sweep
A chimney sweep is a person who inspects then clears soot and creosote from chimneys. The chimney uses the pressure difference caused by a hot column of gas to create a draught and draw air over the hot coals or wood enabling continued combust ...
s. The disease has also been seen in men exposed to mineral oil and those who worked with
coal distillates.
This cancer is also referred to as
epidermoid carcinoma of the scrotum and epithelioma of the scrotum.
Pathogenesis
Chimney sweeps' carcinoma is a
squamous cell carcinoma
Squamous-cell carcinoma (SCC), also known as epidermoid carcinoma, comprises 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 the ...
of the skin of the
scrotum
In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin ...
. Chimney sweeps' carcinoma was first described by
Percivall Pott in 1775 who postulated that the cancer was associated with
occupational exposure to soot.
The cancer primarily affected chimney sweeps who had been in contact with soot since their early childhood. The median age of onset of symptoms in one review was 37.7 years, although boys as young as 8 years old were found to have the disease. It was proposed by W.G. Spencer in 1890 that sweat running down their bodies had caused soot to accumulate in the
rugae of the inferior surfaces of the scrotum, with the resulting chronic irritation causing scrotal cancer, but this was shown to be an incorrect artifact of the method used to stain his microscope slides.
In 1922, R.D. Passey, a research physician at
Guy's Hospital
Guy's Hospital is an NHS hospital founded by philanthropist Thomas Guy in 1721, located in the borough of Southwark in central London. It is part of Guy's and St Thomas' NHS Foundation Trust and one of the institutions that comprise the Kin ...
in London produced malignant skin tumors in mice exposed to an extract made from soot, demonstrating the presence of carcinogenic substances in soot which were the likely cause of cancer of the scrotum in chimney sweeps.
In the 1930s,
Ernest Kennaway
Sir Ernest Laurence Kennaway FRS (23 May 1881 – 1 January 1958) was a British pathologist and Royal Medal winner. He first became interested in natural life when, due to a childhood illness, he was encouraged to spend time outdoors. He was tra ...
and James D. Cook of the Research Institute of the Cancer Hospital in London (later known as the
Royal Marsden Hospital), discovered several
polycyclic hydrocarbons present in soot that are potent
carcinogens
A carcinogen () is any agent that promotes the development of cancer. Carcinogens can include synthetic chemicals, naturally occurring substances, physical agents such as ionizing and non-ionizing radiation, and biologic agents such as viruse ...
:
1,2,5,6-dibenzanthracene;
1,2,7,8-dibenzanthracene; and 1,2-benzpyrene (3) benzo
�yrene.
Benzo(α)pyrene interacts with
deoxyguanosine in
DNA
Deoxyribonucleic acid (; DNA) is a polymer composed of two polynucleotide chains that coil around each other to form a double helix. The polymer carries genetic instructions for the development, functioning, growth and reproduction of al ...
, damaging it and potentially starting the processes that lead to cancer.
Symptoms and signs
The initial lesion is small and painless. It is often described as an itchy sore, wart, or pimple. Often times it may bleed due to scratching.
Socio-historical context
A housing tax, created during the 17th century in England, limited the number of fireplaces per house.
To avoid this tax several chimney pipes would be connected to a single fireplace, resulting in angled pipes.
The odd chimney structures resulted in complex mechanical cleaning methods.
As a result, it was not uncommon for young boys to be hired as chimney sweeps in England in the 1700s and 1800s. Typically, those hired were orphans or children from poor families.
Young children, between the ages 5 and 11, were often hired for their ability to fit through the narrow chimney chutes.
Chimney sweeping was a common practice across Europe and North America.
The disease was mostly found in the United Kingdom, where climbing boys were used. The most likely reason for the high prevalence of the disease in the UK was that chimney chutes were narrower.
Another reason can be attributed to poor hygiene standards in the 18th century: during this time, hygiene standards were lacking and bathing once a year was not uncommon.
Families often shared sleeping blankets and these blankets were often the ones used by the chimney sweeper to collect soot, resulting in further repeated soot exposure.
It was also not uncommon for children to work naked. The lack in hygiene standards coupled with working naked allowed for repeated skin exposure to toxins in chimney soot, a possible cause for this disease.
In the United States, enslaved black children were hired from their owners and used in the same way, and were still climbing after 1875.
Sir Percivall Pott
Sir Percivall Pott
Percivall Pott (6 January 1714, in London – 22 December 1788) was an English surgeon, one of the founders of orthopaedics, and the first scientist to demonstrate that cancer may be caused by an environmental carcinogen, namely chimney sweeps ...
(6 January 1714 – 22 December 1788) London, England) was an English
surgeon
In medicine, a surgeon is a medical doctor who performs surgery. Even though there are different traditions in different times and places, a modern surgeon is a licensed physician and received the same medical training as physicians before spec ...
, one of the founders of
orthopedy
Orthopedic surgery or orthopedics ( alternative spelling orthopaedics) is the branch of surgery concerned with conditions involving the musculoskeletal system. Orthopedic surgeons use both surgical and nonsurgical means to treat musculoskeletal ...
, and the first scientist to demonstrate that a cancer may be caused by an environmental carcinogen. In 1765 he was elected Master of the Company of Surgeons, the forerunner of the
Royal College of Surgeons
The Royal College of Surgeons is an ancient college (a form of corporation) established in England to regulate the activity of surgeons. Derivative organisations survive in many present and former members of the Commonwealth. These organisations ...
. It was in 1775 that Pott found an association between exposure to
soot
Soot ( ) is a mass of impure carbon particles resulting from the incomplete combustion of hydrocarbons. Soot is considered a hazardous substance with carcinogenic properties. Most broadly, the term includes all the particulate matter produced b ...
and a high incidence of chimney sweeps' carcinoma in chimney sweeps. This was the first
occupational link to cancer, and Pott was the first person to demonstrate that a malignancy could be caused by an environmental carcinogen. Pott's early investigations contributed to the science of
epidemiology
Epidemiology is the study and analysis of the distribution (who, when, and where), patterns and Risk factor (epidemiology), determinants of health and disease conditions in a defined population, and application of this knowledge to prevent dise ...
and the
Chimney Sweepers Act 1788.
Pott describes chimney sweeps' carcinoma thus:
It is a disease which always makes it first attack on the inferior part of the scrotum where it produces a superficial, painful ragged ill-looking sore with hard rising edges.....in no great length of time it pervades the skin, dartos and the membranes of the scrotum, and seizes the testicle, which it inlarges, hardens and renders truly and thoroughly distempered. Whence it makes its way up the spermatic process into the abdomen
The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...
.
He comments on the life of the boys:
The fate of these people seems peculiarly hard … they are treated with great brutality … they are thrust up narrow and sometimes hot chimnies, where they are bruised burned and almost suffocated; and when they get to puberty
Puberty is the process of physical changes through which a child's body matures into an adult body capable of sexual reproduction. It is initiated by hormonal signals from the brain to the gonads: the ovaries in a female, the testicles i ...
they become … liable to a most noisome, painful and fatal disease.
The suspected carcinogen was
coal tar
Coal tar is a thick dark liquid which is a by-product of the production of coke and coal gas from coal. It is a type of creosote. It has both medical and industrial uses. Medicinally it is a topical medication applied to skin to treat psoria ...
, and possibly
arsenic
Arsenic is a chemical element; it has Symbol (chemistry), symbol As and atomic number 33. It is a metalloid and one of the pnictogens, and therefore shares many properties with its group 15 neighbors phosphorus and antimony. Arsenic is not ...
.
Diagnosis
Diagnosis of scrotal carcinoma is by biopsy of the scrotal lesion.
There are several different tests involved in staging, including MRI of the scrotum and abdominopelviscrotal ultrasound.
Ray and Whitmore proposed a staging system based on the level of metastasis.
It is the most commonly used system.
There are four stages of the cancer, listed as Stage A through to Stage D.
Under Stage A there are two substages, Stage A1 and Stage A2.
Stage A1 is when the disease is localized in the scrotum.
Stage A2 is when the disease moves to surrounding areas, including the penis, testis, pubic bone, and perineum.
During Stage B, the disease metastasizes regionally.
At this point in the disease, the cancer and/or tumor is resectable.
At Stage C, the disease further metastasizes, however, at this point is it no longer resectable.
Distant
metastasis
Metastasis is a pathogenic agent's spreading 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, ...
occurs during Stage D of the disease. At this point, it moves past the regional nodes, which is rare.
Prognosis
Chimney sweeps' carcinoma prognosis depends heavily upon the presence or absence of
lymph node involvement.
Removing the tumor during initial surgery is a leading factor in prognosis.
Survival rate is based upon spread to lymph nodes. There is an about 25% 5-year survival rate in cases in which the
inguinal lymph nodes
Inguinal lymph nodes are lymph nodes in the groin. They are situated in the femoral triangle of the inguinal region. They are subdivided into two groups: the superficial inguinal lymph nodes and deep inguinal lymph nodes.
Superficial inguinal ly ...
are involved.
There is no survival rate if
external iliac lymph nodes
The external iliac lymph nodes are lymph nodes, from eight to ten in number, that lie along the external iliac vessels.
They are arranged in three groups, one on the lateral, another on the medial, and a third on the anterior aspect of the vessel ...
are involved.
Treatment
Treatment was by surgery. More specifically, wide excision with a 2-3cm margin.
It is also recommended that the surrounding subcutaneous tissue is removed with the tumor itself.
Scrotal contents are usually only removed if involved through the tumor.
Radiation therapy and chemotherapy can also be considered.
Prevention
Incidence of chimney sweeps' carcinoma was reduced when protective work clothes were introduced.
The
Chimney Sweepers Act 1788 (
28 Geo. 3. c. 48), the first act to protect child workers,
outlined appropriate work attire.
This act stated that the minimum working age was 8 years old.
Improved personal hygiene also helped in lowering incidence of the cancer.
In 1803, two societies were formed to protect children in the chimney sweeping industry.
Parliament passed the
Chimney Sweepers Act 1834 (
4 & 5 Will. 4. c. 35) in response to child labor exploitation concern.
This law forbade children under 10 years old from working.
These acts also required that improvements be made to chimney structures.
Soon after the
Chimney Sweepers and Chimneys Regulation Act 1840 (
3 & 4 Vict. c. 85) changed the minimum age to 16 years old.
This new law also suggested that those under 21 not work in the chimney sweeping industry.
The
Chimney Sweeepers Act 1875 (
38 & 39 Vict. c. 70) forbade this practice. Climbing boys were also used in some European countries.
Lord Shaftesbury, a
philanthropist
Philanthropy is a form of altruism that consists of "private initiatives for the public good, focusing on quality of life". Philanthropy contrasts with business initiatives, which are private initiatives for private good, focusing on material ...
, led the later campaign.
However, these laws were typically ignored due to lack of enforcement strategies.
In 1863, the Children's Employment Commission evaluated child employment to ensure the acts of Parliament set in place were followed.
Their report showed that child employment even had increased since the introduction of the Chimney Sweepers and Chimneys Regulation Act 1840.
Related diseases
Decades later, it was noticed to occur amongst gas plant and
oil shale
Oil shale is an organic-rich Granularity, fine-grained sedimentary rock containing kerogen (a solid mixture of Organic compound, organic chemical compounds) from which liquid hydrocarbons can be produced. In addition to kerogen, general compos ...
workers, and it was later found that certain constituents of tar, soot, and oils, known as
polycyclic aromatic hydrocarbons
A Polycyclic aromatic hydrocarbon (PAH) is any member of a class of organic compounds that is composed of multiple fused aromatic rings. Most are produced by the incomplete combustion of organic matter— by engine exhaust fumes, tobacco, incin ...
, were found to cause cancer in laboratory animals. The related cancer is called
mule spinners' cancer.
References
Bibliography
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*
*
*
*{{cite journal, last=Waldron, first=H.A., year=1983, title=A brief history of scrotal cancer
, journal=British Journal of Industrial Medicine, volume=40, pages=390–401
, pmc=1009212
, pmid=6354246, issue=4
, doi=10.1136/oem.40.4.390
Carcinoma
Occupational cancer
Chimney sweeps
Scrotum
Polycyclic aromatic hydrocarbons