Medico Legal Issues in Oncology

The reason for this is that the vast majority of every-day medicine is conducted within a safety envelope of normal clinical practice with relatively well demarcated boundaries. Rather like a ski piste where there are a few different ways to get down, but the edges are clearly marked and most people stay within those boundaries.

Clinical negligence however, usually represents a significant step outside the normal bounds of conventional medical practice and as with any off-piste adventure, the final outcome is unpredictable and a variety of outcomes, both good and bad are possible.

Oncology is a common area for clinical negligence claims. Part of this is due to the increasing frequency of cancer in the UK population – 50% of our generation will be diagnosed with cancer in our lifetime. Fortunately advances in cancer treatment mean that over 50% of cancer patients can now expect to get cured of their disease, and others will live for many years, kept alive by new treatments.

An increasing expectation by the public of their general practitioners and hospital specialists also plays a part. My area of clinical practice is in head and neck cancer – a term covering cancers arising in the mouth, throat, neck, voice box and thyroid gland. I also specialise in lung cancer. Both of these tumour types are difficult to diagnose in the early stages because they present with symptoms which are very prevalent in the general population due to other non-serious diseases. Head and neck cancer for example can present with some of the following symptoms: mouth ulcer, sore throat, ear ache, hoarse voice or swelling of lymph nodes in the neck. All of us have had these symptoms in our life time and usually they are caused by transient viral infections which are self limiting and settle after a few days or weeks. Similarly Lung cancer at its earliest stages presents with a persistent cough which is often normal in the heavy smokers who are at risk of this disease.

General Practitioners deal with patients with these symptoms all the time and they have to keep in mind that very occasionally there may be something more
sinister behind these common complaints. The National Institute for Clinical Excellence (NICE) publish guidance documents which list symptoms which should initiate an urgent hospital referral under the urgent referral for suspected cancer pathway, or “two week wait”. These guidelines stipulate which symptoms or combination of symptoms should lead a GP to refer, and usually they focus on persistent or worsening and unexplained symptoms over a given number of weeks. Patients who fulfil criteria for referral should be referred urgently as suspected cancer cases and have to be seen within 14 days by the hospital specialist. Experts in General Practice commenting on cancer cases often use the NICE guidelines to decide on breach of duty when considering the actions of General
Practitioners in clinical negligence cases. Examples of the NICE guidance for head and neck cancer are shown in Table 1.

In my experience, oncology clinical negligence cases fall into a number of distinct categories. The most common is delay in diagnosis. Typically it is alleged that a patient had a delay in diagnosis due to their perceived lack of attention from their GP or hospital specialist. This is a retrospective opinion formed when a cancer diagnosis is made weeks or months after the issue was first raised by the patient with their doctor. Initially an assessment of breach of duty is required, and this will need to be determined by a specialist expert in general practice. These reports often rely heavily on the compliance with NICE guidelines for referral for suspected cancer (see above). For allegations against hospital doctors an opinion from the appropriate medical specialty is required.

Causation opinion is usually the province of an oncologist who will try to analyse the staging and prognosis of the cancer at different time points relating to the case. Staging is a process which describes the extent of the cancer at any one point in time. The most detailed staging system is the Tumour, Node, Metastasis (TNM) system. To understand this it is important to have a little bit of knowledge about cancer biology. When a cancer develops in a particular organ it usually grows steadily in size. The size of the tumour is usually measured in centimetres, and usually it is the size of the primary tumour which determines its T-stage, T1 representing the smallest size, and T2, T3, T4 representing progressively larger tumours. At some stage in tumour development, some cancer cells migrate from the primary tumour and metastasize (spread) to lymph nodes. These lymph nodes may swell up and the size of lymph nodes, or extent of lymph node spread is categorised by “N” in the TNM system. N0 represent no lymph node spread, and N1, N2, N3 represents progressively more extensive lymph node spread. The T and N categories are different for each cancer type and the definitions of these categories make up a substantial component of any oncology text book and exam. M stands for metastases (spread of cancer) to other distant organs. Usually this is M0 if no metastases are present or M1 if they are present.

Each TNM combination for any particular tumour type can be translated into a percentage cure rate or average survival time which is usually what the solicitor or Barrister requires for their causation argument. For common cancers such as lung cancer, colon cancer, prostate cancer and breast cancer the prognosis data are relatively accurate and can be provided for contemporary UK patients based on information from research studies or population databases. For example a T1AN0M0 lung cancer defines a lung tumour less than 2cm in size with no spread, and has a cure rate with surgery of 90%, compared to a stage T4N2M0 lung cancer which is a more advanced cancer with a cure rate of less than 20%. For rarer types of cancer, the literature may yield only small numbers of reported cases which reduces the accuracy of outcome statistics, or old studies of patients treated many years ago with old medical technologies. This sometimes causes
problems if data used to provide causation evidence prove controversial to the court.

Evidence based on patients treated in research studies is often of the best quality, but has a potential difficulty in that these individuals entered into trials usually have a slightly better outcome than the average population due to selection of only the fittest patients to enter clinical trials, or the better treatments available in university departments compared to smaller cancer centres.

Almost always, the staging of a cancer at the actual time of diagnosis is accurate, as the patient will have undergone extensive investigation including scans and other procedures which allow a full TNM and prognosis to be determined.

What is much more difficult for the oncologist to determine is what size the tumour would have been at a date prior to the diagnosis. For example consider a situation of a patient who attended their GP on several occasions with a symptom of persistent cough and was reassured without investigation that it was due to a chest infection. Six months later they saw another GP with the same persisting symptom and were referred to hospital where a lung cancer was diagnosed. I am often asked to comment on what stage the cancer would have been, and what the treatment and cure rate would have been had a diagnosis been made 6 months earlier. Of cause this is impossible to answer with accuracy, and we have to rely on data on average tumour growth rates which can vary widely between one patient and another and so may be controversial. Occasionally when reading the medical notes, I find that the patient had some form of scan or investigation performed prior to their cancer diagnosis and that can prove very helpful in providing data to retrospectively stage the cancer toa specific point in time.

One regrettable but surprisingly common version of this scenario is the missed incidental finding. For example, a patient attended an accident and emergency department with a broken hip, and as part of a pre-operative assessment had a chest X-ray. The X-ray was briefly reviewed by the anaesthetist prior to performing a general anaesthetic, but was never reported formally. They recovered from their operation and a year later the patient was diagnosed with a lung cancer. A retrospective review of the X-ray determined that the tumour was visible at a much smaller size a year before. Such cases are usually straight forward for the oncologist as TNM can be accurately determined at both time points and the prognosis at each time point calculated.

Government targets for cancer diagnosis and treatment have been very important in the NHS for the last decade. Patients suspected by their GP to have cancer must be seen within 14 days of referral and start treatment within 62 days. Patients diagnosed with cancer by other referral routes (not on the 14 day pathway) must start treatment within 31 days of a diagnosis and treatment pathway being agreed with the patient. Over 95% of cancer cases should be discussed at an appropriately appointed multi-disciplinarily team (MDT). Failure to achieve any of these government targets can be considered to be clinically negligent on the basis that no responsible body of specialists would accept not achieving these targets.

In my experience one of the most common causes of delays in starting treatment is due to transfer of care from one hospital to another, or referral from one department to another within the same hospital due to poor communication.

Finally, errors in treatment make up a minority of oncology clinical negligence cases. All oncology departments in the UK have strong clinical governance frameworks. This usually means that all treatments with radiation and chemotherapy are protocol based and have robust quality assurance procedures around their use. Chemotherapy prescriptions go through several layers of checking before their administration to patients and radiotherapy is similarly checked at several stages during planning and treatment. Nevertheless rare mistakes, usually though human error, are occasionally seen and can lead to damage to patients.

Table 1.
2015 NICE referral guidelines for head and neck cancer
1.8 Head and neck cancers

Laryngeal cancer
1.8.1 Consider a suspected cancer pathway referral (for an appointment within 2 weeks) for laryngeal cancer in people aged 45 and over with: persistent unexplained hoarseness or an unexplained lump in the neck.

Oral cancer
1.8.2 Consider a suspected cancer pathway referral (for an appointment within 2 weeks) for oral cancer in people with either: unexplained ulceration in the oral cavity lasting for more than 3 weeks or a persistent and unexplained lump in the neck.

1.8.3 Consider an urgent referral (for an appointment within 2 weeks) for assessment for possible oral cancer by a dentist in people who have either: a lump on the lip or in the oral cavity or a red or red and white patch in the oral cavity consistent with erythroplakia or erythroleukoplakia.

1.8.4 Consider a suspected cancer pathway referral by the dentist (for an appointment within 2 weeks) for oral cancer in people when assessed by a dentist as having either: a lump on the lip or in the oral cavity consistent with oral cancer or a red or red and white patch in the oral cavity consistent with erythroplakia
or erythroleukoplakia.

Thyroid cancer
1.8.5 Consider a suspected cancer pathway referral (for an appointment within 2 weeks) for thyroid cancer in people with an unexplained thyroid lump.