General practitioners and cancer

Primary care has not traditionally been seen as central in the planning and provision of oncology services. This partially reflects the infrequency with which cancer is diagnosed by individual general practitioners and the dissociation between general practitioners and large parts of the care of patients with cancer. Nevertheless, as doctors concerned with the comprehensive, coordinated, and continuous care of individuals, families, and, increasingly, populations, general practitioners do have an important role in cancer, and the British government's desire to improve cancer outcomes relies heavily on general practitioners playing their part.

The early detection of cancer by either screening or the prompt recognition of potentially important symptoms is already the province of primary care. General practitioners occupy a critical position in ensuring the effectiveness of national cancer screening programmes as well as providing effective and cost effective advice on specific primary prevention strategies.¹ In the United Kingdom's breast and cervical cancer screening programmes primary health care team members have both developed and been delegated important roles in providing information and advice to women at all stages of the screening process. Indeed, the attitudes of general practitioners and practice nurses to breast screening are critical in influencing women to attend, and practice administrative staff are key in maintaining accurate patient notification lists.² In the French screening programme for colorectal cancer the involvement of primary care clinicians has been shown significantly to increase patient participation rates in faecal occult blood testing.³

Patients often do not understand the rationale for screening or the inevitability of some false positive and false negative results. General practitioners thus have an important and expanding role in ensuring that their patients truly understand these issues and the need for continuing vigilance about new symptoms. In helping patients to make informed choices about screening—for example, in relation to prostate cancer—a group of Canadian general practitioners is leading the way by developing “physician-patient partnership” papers.⁴

For many patients the general practitioner's most important role is responding appropriately to a worrying symptom. In a recent review of complaints about general practitioners received by the Medical Defence Union failure or delay in diagnosis accounted for 28% of the notifications in one year.⁵ The most common condition associated with diagnostic failure or delay was missed malignancy. At a population level Roetzheim et al have shown that the supply of primary care physicians is significantly correlated with the stage at diagnosis of patients with colorectal cancer: as the supply of primary care physicians increased, the odds of late-stage diagnosis decreased.⁶

Diagnosing cancer in primary care is often difficult. Many cancers present with common symptoms such as persistent cough or non-specific abdominal pain yet few patients with such symptoms turn out to have cancer.⁷ Primary care clinicians need to be able to discriminate which patients within a relatively unselected population have a higher likelihood of malignant disease. Unfortunately there is little research in the community to show just how useful a particular symptom is at predicting a certain disease, which symptoms are not useful, and which symptoms will rule out disease. This problem has recently been highlighted for both cough and lung cancer⁸ and haematuria and urological malignancies.⁹

Apart from the traditional features in the clinical history—such as change in bowel habit, rectal bleeding, abdominal pain, and unexplained weight loss in colorectal cancer—there is evidence that other information available to general practitioners might help in identifying malignancy. For example, over 30 years ago Pereira-Gray noted the importance of behaviour change—such as a recent decision to stop smoking—in indicating a likelihood of malignancy.¹⁰ Moreover, dynamic evidence, such as the addition of new symptoms, the persistence of a symptom, or changes in the characteristics of a problem, is particularly relevant in general practice, where patients are assessed over time.

General practitioners are gradually becoming more involved in managing patients with cancer. The traditional focus on symptom control in palliative-terminal care is being extended to incorporate, for example, the administration of hormonal and chemotherapeutic agents for both palliation and cure. General practice based follow up of patients with breast cancer has been shown to be acceptable to patients and does not delay the detection of recurrences.¹¹,¹²

Primary care oncology has come of age. Policymakers, planners, and researchers need now more formally to recognise the roles and responsibilities of the primary care team in important aspects of oncology. This recognition must be supported by the development of high quality and generalisable research that addresses fundamental clinical issues at the heart of primary care. The major cancer and research charities must be persuaded to fund research into recognising cancer in primary care. In addition primary care professionals must themselves become more involved in the development of the cancer screening programmes and new therapeutic initiatives which they will eventually play a part in managing.