The Institute of Biomedical Science

www.ibmscongress.com

The history of cytology

Cytology is often thought of as a pathology discipline of the 20th and 21st century but it has roots going back to more than 300 years ago.

The English scientist Robert Hooke made the first observations of cells in 1665. He used a crude microscope of his own invention to examine a variety of objects, including a thin piece of cork in which he noted rows of tiny boxes that made up the dead wood's tissue and coined the term cell because the boxes reminded him of the small cells occupied by monks in a monastery. Whilst Hooke was the first to observe and describe cells, he did not comprehend their significance.

Antoni van Leeuwenhoek built microscopes consisting of double-convex lenses mounted between brass plates and held close to the eye. Through these he was able examine objects mounted on pinheads magnifying them up to 300 times, a power that far exceeded that of earlier compound microscopes. In 1674 he gave the first accurate description of red blood corpuscles.

Muller set the foundations of clinical cytology as we know it today in 1838 when he published On the nature and structural characteristics of cancer and those morbid growths that may be confused with it. He was ahead of other microscopists who were then still struggling to recognize normal cells, for he was able to describe cells from carcinomas and distinguish them from sarcomas.

One of the first occasions that cytology was mentioned as a diagnostic technique was 150 years ago in 1851. Dr Walshe, an Englishman, wrote in reference to lung cancer "if the cancer had softened, the microscopic characters of that product may be found sometimes in sputa".

In 1854 Lionel Beale, Professor of Physiology and General and Morbid Anatomy at King's College London, included a drawing of unstained cancer cells in his book The microscope and its application to clinical medicine.

In England in 1861, a drawing was published of cancer cell exfoliated from a patient who had died of cancer of the pharynx. Also in 1861, Lebert, of Switzerland, published an atlas that included an illustration of cells exfoliated from cancer of the cervix. 1896 saw, Bahrenberg, of Ohio introduce the technique of stained cellblocks to examine cells from serous fluids.

Ellis and Martin wrote of their experiences of aspiration cytology on patients at the Memorial Hospital for Cancer and Allied Diseases in New York in 1926. The years up to 1941 included only a few publications mentioning cytology; of note are those by Dudgeon, Bamforth, and Wrigley, all of England, who published a series of papers on respiratory cytopathology.

Papanicolaou had realized the importance of wet fixation and developed a technique for fine staining of cells. He was working on the oestrous cycle of mammals and was examining cellular samples from the vagina of guinea pigs. In 1928 he published a paper entitled New cancer diagnosis.

In 1941 Papanicolaou and Traut, of Cornell University, published a paper in the American Journal of Obstetrics and Gynaecology entitled The diagnostic value of vaginal smears in carcinoma of the uterus. This was followed in 1943 by their monograph Diagnosis of uterine cancer by the vaginal smear. Gynaecologists were quick to grasp the importance of these publications and cervical screening commenced in the United States.

By 1945, Meigs at Massachusetts Hospital had confirmed the soundness of the cytological method in the diagnosis of cervical cancer and its in situ phase.

Cervical screening began in Britain in the mid-1960s but by the mid-1980s, although many women were having regular smear tests, there was concern that those at greatest risk were not being tested, and that women who had a positive results were not being followed up and treated effectively.

The NHS Cervical Screening Programme was set up in 1988 when the Department of Health instructed all health authorities to introduce computerised call-recall systems and to meet certain quality standards.

The effectiveness of the screening programme is evident in figures showing that in England in 2002 927 women died of cervical cancer.

The next steps for cytology have commenced with the introduction of Liquid Based Cytology and the testing for Human Papilloma Virus.

June/July 2004

Tags: Cellular pathology, Cytology, Transfusion science, History