Breast cancer survival

Cancer of the breast has been described for centuries; the recognition of the “bulging tumours of the breast” is recorded in the valuable Edwin Smith Papyrus of 1600 B.C. found at Thebes in Egypt in 1862 and translated by Breasted.¹ Treatment was limited to two methods – either burn the lesion with fire, or remove it with a sharpened instrument.

Leonides, a Greek physician of the first century A.D. working in the great medical school at Alexandria, is believed to have been the first to carry out a surgical removal of the breast.² His technique was to cut into normal breast tissue wide of the tumour. Leonides employed cautery to control bleeding, and to destroy residual tumour. He also advised that surgery was not indicated if the whole breast was hardened, or if the tumour was fixed to the chest wall. It is probable that Leonides was the first to recognise that breast cancers spread to the axilla. Nearly two millennia were to pass before any innovation would develop in the battle against breast cancer.

In the late 1800’s Dr William Halsted had described the radical mastectomy that would be carried out for nearly 100 years and maybe for much longer.³ The procedure involved:

• Wide excision of the tumour and skin, covering the defects with grafts
• Routine removal of the pectoralis major muscle
• Routine axillary dissection

This was a destructive and disfiguring operation, carrying with it a high risk of post-operative disability such as lymphoedema. However survival rates improved to about 40% over five years.

As the nineteenth century was ending, two discoveries were made that had huge implications for the future management of breast cancer. The first was x-rays, which was to lead to mammography and radiotherapy. The second was the revelation that breast cancer was hormone dependent.

By the end of World War II the modalities, which would be used to treat breast cancer were all in existence. However, there were a wide variety of opinions, which produced confusion. Multiple papers appeared in the literature, which expressed the personal opinions of authors who used unconvincing small series of cases to support their hypotheses.

However, there were two papers, which appeared in 1948, which were ultimately to produce a revolution in breast cancer management, and would become accepted as the “gold standard” in the management of localised disease. The most important of these papers was from the Middlesex Hospital in London. David Patey described a modified technique of the standard radical mastectomy by preserving the pectoral muscles thereby avoiding a major component of the disfigurement.⁴ It was the forerunner of the modern trend towards conservative surgery. However, it did little to improve survival, which hovered around 50%.

In 1963 an article appeared in the British Medical Journal by Williams, Murley and Curwen.⁵ It was a retrospective study of cases treated by simple, radical and modified mastectomies with or without radiotherapy. Their conclusion reflected some of the feelings of the time: “The most impressive finding in this series is the remarkable similarity in survival rates following different methods of treatment.”

From here on there was a ground swell of opposition to radical surgery, which went hand in hand with increasing knowledge of the disease process. Bernard Fisher from the University of Pittsburgh asserted that breast cancer was a systemic disease and that it’s course was determined by a biological struggle between tumour and host, which in turn meant that management of the disease had to be re-evaluated. Referring to Halsted’s rationale for radical mastectomy, Fisher wrote in 1970 that, “…either the original surgical principles have become anachronistic or, if they are still valid, they were conceived originally for the wrong reasons.” ⁶

At the same time, the biomedical sciences were developing at an impressive rate allowing the dawn of a new era. The term “chemotherapy” had been coined in 1898, but it was not until the mid 50’s that adjuvant chemotherapy for breast cancer became widely accepted.

During the 60’s the efficiency of radiotherapy delivery was improved dramatically, and confidence in its ability to “mop-up” tumour cells left behind following surgery grew.

During the early 70’s several significant trials proved that excision of the primary tumour, “lumpectomy,” followed by whole breast irradiation was as effective as total mastectomy for both local and ultimate disease control of most early-stage cases and was an obvious cosmetic improvement.

By this time the five-year survival rate had risen to about 70%. The cure rate also rose. Post-operative morbidity rates dropped which was in keeping with the trend towards conservative surgery.

The introduction of more sophisticated adjuvant chemotherapy and hormonal manipulation with the use of Tamoxifen in the mid seventies produced a further survival improvement of 10%, raising the five-year survival to 80%.

Continuing development of new age adjuvant therapies together with earlier diagnosis (aided by the Commonwealth Governments BreastScreen programme) has ensured continued improvement to the present where relative five-year survival for breast cancer in the Australian population has risen to 86%. Relative five year survival describes the percentage of patients who live at least five years after the cancer is first diagnosed. It excludes patients who die of cause other than the cancer.) This is demonstrated in Figure 1.⁷

Figure 1: Relative survival percentages by period of diagnosis in the Australian female population.

Figure 2 shows the same data for The Strathfield Breast Centre’s patient population. The improved survival is in part due to improved surgical technique, and in part due to better use of chemotherapy, hormone therapy, radiotherapy, and more recently, the new age monoclonal antibodies such as Herceptin (transtuzumab).

Figure 2: Relative survival percentages by period of diagnosis in The Strathfield Breast Centre’s population.

Women diagnosed with breast cancer today, have a much brighter future than those who faced the diagnosis generations or centuries ago. However, the story of breast cancer is incomplete – ultimately what we’d like too see is breast cancer becoming a preventable disease. We look forward to the news reader telling us “Today doctors at (some) medical institution announced that a (vaccine?) prepared from the (?prions) of breast cancer resulted in immediate and total disappearance of all signs of the disease. Further studies are planned to further explore this promising development.” When this happens, the story may be nearing completion.

References:

1. Breasted JH, editor. The Edwin Smith Surgical Papyrus. Chicago, IL: The University of Chicago Press; 1930, Special Edition. 1984. The Classics of Surgery Library. Division of Gryphon Editions, Ltd. Birmingham (AB). Frontispiece.
2. De Moulin D. A short history of breast cancer. Boston: Martinus Nijhoff; 1983. p. 1–107.
3. Halsted WS. The results of operations for the cure of cancer of the breast performed at the Johns Hopkins Hospital from June 1889 to January 1894. Johns Hopkins Hospital Reports. Baltimore 1894–95;4:297–350.
4. Patey DH, Dyson WH. The prognosis of carcinoma of the breast in relation to the type of operation performed. Br J Cancer 1948;2:7-13
5. Williams IG, Murley RS, Curwen MP. Carcinoma of the female breast. Conservative and radical surgery. Br Med J 1953;2:787-96.
6. Fisher B. The surgical dilemma in the primary therapy of invasive breast cancer: a critical appraisal. Current problems in surgery. Chicago: Year Book Medical Publishers Inc.;1970.
7. AIHW & NBCC 2006. Breast Cancer in Australia. An Overview, 2006. Cat No CAN 29. Canberra AIHW.