2 The condition, current treatments and procedure
2.1 Rectal cancer is a common form of bowel cancer. The risk of developing it rises with age. Symptoms include rectal bleeding, obstruction, perforation, pain and discharge. Symptoms may result from the tumour invading organs near the rectum (such as the bladder). Early stages of rectal cancer may be asymptomatic and some patients present with locally advanced rectal cancer, commonly defined as T3 or T4 primary tumours or nodal metastases, or stage 2 (T3 to T4, node negative) or stage 3 (T1 to T4, node positive).
2.2 There is variation in the clinical management and treatments offered for locally advanced rectal cancer. Radical surgery in the form of total mesorectal excision (TME) offers the best chance for cure in some patients. Patients who choose not to have surgery, or are not fit enough to have it, may have neoadjuvant chemoradiotherapy (such as external beam radiotherapy, with or without brachytherapy). The aim is to reduce the tumour size, alleviate symptoms, and improve survival and quality of life.
2.3 Low-energy contact X‑ray brachytherapy (CXB) is also known as the Papillion technique. It may be given with external beam radiotherapy or chemotherapy, or both. It is usually delivered in a day-patient setting. The patient is given an enema before treatment to empty the rectum. With the patient in a knee-to-chest, prone jack-knife or supine position, local anaesthesia and glyceryl trinitrate are applied to the anal sphincter to numb the area and relax the sphincter muscles. A sigmoidoscope is inserted through the anal sphincter to ascertain the size and position of the tumour. Then a rigid endorectal treatment applicator is inserted and placed in contact with the tumour. A contact X‑ray tube is introduced into the applicator. It emits low-energy X‑rays that penetrate tissue by only a few millimetres, minimising damage to deeper tissues.