Chimney Sweeps' Carcinoma - History

History

Sir Percivall Pott (6 January 1714 – 22 December 1788) London, England) was an English surgeon, one of the founders of orthopedy, 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. It was in 1775 that Pott found an association between exposure to soot and a high incidence of Chimney Sweeps' carcinoma, a scrotal cancer (later found to be squamous cell 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 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(sic), hardens and renders truly and thoroughly distempered. Whence it makes its way up the spermatic process into the abdomen.

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 they become ... liable to a most noisome, painful and fatal disease.

The carcinogen was thought to be coal tar possibly containing some arsenic.

Though Pott wrote no further papers on the subject, clinical reports began to appear suggesting that others had seen it without realising what it was and like Pott had said:

....it is generally taken, both by patient and surgeon for venereal and treated with mercurial .

The disease was usually preceded by the development of hyperkeratotic lesions on the scrotum, which was what the sweeps called soot warts. These could be benign; sweeps often removed them themselves by trapping them in a split cane and cutting them off with a pocket knife. For instance:

"he... seized with a split stick and cut off with a razor. He remarked that it was not very painful. He resumed work the following day."

But if the lesion had become malignant it was far more serious. Patients frequently delayed seeking medical opinion, and when they did many were in dreadful state. A 28 year old sweep approached Jefferies in 1825, who describes his condition:

"The sore occupies the whole of the left side of the scrotum and the inner angle of the thigh, extending from the anus to the posterior inferior spinous process of the ileum, presenting a surface as large as a man's open hand, with hard indurated edges and irregular margins, discharging a thin sanies, which is extremely offensive; the left testicle is entirely denuded, and projects from its centre; in the left groin is a mass of indurated glands, the size of a goose's egg, which appears to suppurate in the right groin: there is likewise an ulceration, of the same malignant nature, about the size of a half-crown (5 cm). . ." Despite the appearance of this growth, the unfortunate man was in no pain and his only complaint was that about 10 days before his admission he had bled from his groin and lost about a pint of blood.Even this, however, had not unduly affected his constitution.