When it comes to bowel cancer, he is one of the very best specialists: his high level of surgical expertise is particularly evident in highly complex procedures – such as those for rectal cancer. In this field, Prof. Dr. med. Christoph A. Maurer and his team have even developed their own surgical technique. The Leading Medicine Guide spoke to the internationally renowned surgeon about, among other things, what constitutes a successful operation for this type of cancer.
“Surgical precision is crucial!”
The rectum – also known as the lower part of the large intestine – is the final section of the large intestine. The rectum is on average about twelve centimeters long and adjoins the anal canal. The experienced visceral surgeon Prof. Dr Christoph A. Maurer points out that, of all the organs in the abdominal cavity, the rectum is the one most frequently affected by malignant tumors. But that is by no means the only interesting piece of news the specialist has in store.
Leading Medicine Guide: Professor Maurer, you say that rectal cancers account for around forty per cent of all colon tumors. That is a significant figure. Who is most commonly affected by rectal tumors?
Prof. Dr. med. Christoph A. Maurer: First of all, it must be noted that a family history of inherited genetic mutations can be identified in less than ten per cent of all patients. So we have around ninety per cent of cases that show no family history – and in these cases, rectal cancer rarely occurs before the age of fifty. Furthermore, the tumor develops slowly over several years and, in around 97% of cases, follows the so-called adenoma-carcinoma sequence.
Leading Medicine Guide: Adenoma-carcinoma sequence?
Prof. Dr. med. Christoph A. Maurer: In the adenoma-carcinoma sequence, a small, flat polyp first develops, which slowly grows into an adenomatous mass or a mushroom-shaped adenoma. This intestinal polyp eventually becomes malignant and develops into an invasive tumor, i.e. cancer. This process can take seven to ten years.
Leading Medicine Guide: Are there any risk factors that could be avoided?
Prof. Dr. med. Christoph A. Maurer: Modifiable risk factors for rectal cancer include obesity, smoking and a high intake of red meat, particularly when char-grilled.
Leading Medicine Guide: And how do I know if I have rectal cancer? Through severe pain?
Prof. Dr. med. Christoph A. Maurer: A common statement from patients is: ‘I don’t feel anything, so I don’t have bowel cancer!’ But this is a misconception. The by far most commonly reported symptoms of rectal cancer are changes in bowel habits or the passage of bright red blood from the anus. The latter is often mistakenly attributed to hemorrhoids – which can be fatal. Pain or bowel obstruction are late-stage symptoms and therefore indicative of a tumor that is already at an advanced stage.
Leading Medicine Guide: If the diagnosis is rectal cancer – how is the treatment plan devised?
Prof. Dr. med. Christoph A. Maurer: First of all, the diagnosis is made via a colonoscopy and the removal of a tissue sample, known as a biopsy. The extent of the tumor is then determined, usually by means of a CT scan of the abdomen and thorax and an MRI scan of the pelvis. Using this information, a treatment plan is drawn up for the patient at our interdisciplinary tumor board meeting, taking into account the individual tumor stage. Often, the three treatment modalities – chemotherapy, radiotherapy and surgery – are required in sequence.
Leading Medicine Guide: Are rectal cancer operations dangerous procedures?
Prof. Dr. med. Christoph A. Maurer: That also depends on the stage of the disease. In any case, however, rectal cancer surgery falls within the field of highly specialized abdominal surgery. In Switzerland, it may now only be performed by a handful of centers. To qualify, a center must meet numerous requirements – for example, a minimum annual case load per clinic and per surgeon.
Leading Medicine Guide: But your centers and you yourself meet these requirements, don’t you?
Prof. Dr. med. Christoph A. Maurer: Yes, both Solothurner Spitäler AG and the Hirslanden Clinic in Bern are regarded as leading centers of excellence for abdominal diseases, partly because they consist of a network of gastroenterologists, visceral surgeons, radiation oncologists, oncologists and pathologists. It is precisely the interdisciplinary tumor board – that is, the close collaboration on every single case – that ensures our patients receive significant added value in terms of medical expertise.
Leading Medicine Guide: That is surely also because such operations are not exactly straightforward...
Prof. Dr. med. Christoph A. Maurer: Exactly. The surgical field deep within the pelvis, the often confined pelvic space, the not uncommon obesity among patients and, in men, the occasionally enlarged prostate make these rectal operations challenging. However, with the appropriate experience and expertise, these procedures are almost without exception performed precisely, with minimal blood loss and without complications.
Leading Medicine Guide: With tumors in the rectum, there is certainly a fear of losing the anus and having to live with a stoma.
Prof. Dr. med. Christoph A. Maurer: With the right expertise, pre-operative diagnostics and surgical techniques are now so advanced that a rectal resection is rarely necessary. In our patient cohort, only five to six per cent experience the loss of the anus and, consequently, normal continence as a result of the disease.
Leading Medicine Guide: Does this apply to the whole of Switzerland?
Prof. Dr. med. Christoph A. Maurer: Unfortunately not; these encouraging figures are attributable to our expertise. Across Switzerland as a whole, a rectal resection is performed in an average of twenty-five per cent of all patients with rectal cancer.
Leading Medicine Guide: Can I be cured of my rectal cancer at all?
Prof. Dr. med. Christoph A. Maurer: The long-term prognosis depends, on the one hand, on the tumor stage at diagnosis and, on the other hand, on the quality of the surgery. And it is precisely here – namely in the quality of the surgery – that the precise execution of what is known as a total mesorectal excision is crucial. In this technique, the fat pad that supports the lymphatic vessels and lymph nodes and surrounds the rectum is meticulously dissected from the small pelvis along a thin layer of connective tissue. This mesorectal fat pad is, in fact, the site where the tumor can directly infiltrate or metastasise, i.e. form secondary tumors. To prevent tumor recurrence in the small pelvis, this fatty tissue – the mesorectum – must therefore be completely removed. In our practice, the local recurrence rate after a five-year follow-up period is less than three per cent; even in long-term follow-ups, we remain below five per cent. Incidentally, we published a book on our method for German-speaking surgeons back in 1998. The book is called ‘The Concept of Total Mesorectal Excision’ and was published by Karger Verlag.
Leading Medicine Guide: Is additional chemotherapy and radiotherapy still necessary at all?
Prof. Dr. med. Christoph A. Maurer: The refinement and optimization of surgical techniques in the small pelvis now allows us to dispense with radiotherapy in around sixty per cent of patients – specifically those patients for whom, according to guidelines, such therapy would be recommended following conventional surgery. Consequently, a significant proportion of patients are spared the potential side effects of radiotherapy, without compromising on local recurrence rates or long-term survival. In contrast, in intermediate and advanced tumor stages, chemotherapy is recommended for the prevention or treatment of distant metastases in the liver or lungs. Recently, chemotherapy has increasingly been administered prior to surgery.
Leading Medicine Guide: On average, how much of their quality of life do patients lose following rectal cancer surgery?
Prof. Dr. med. Christoph A. Maurer: In my research team, we have developed a rectal replacement procedure. In this procedure, the large intestine, which is sutured to the anal canal, is reconstructed in such a way that a stool reservoir develops, similar to that of a natural rectum. In addition, a peristaltic brake is created – meaning the forward-propelling bowel movement slows down before the anal canal. As a result, patients are much less likely to be troubled by frequent bowel movements, loose stools or even incontinence following the surgical procedure. After just one year, our patients report hardly any complaints in this regard. By refining our surgical technique and deepening our anatomical knowledge of the pelvis, we are now also able to spare the nerves to the bladder and genitals to a great extent. Consequently, urogenital dysfunction occurs much less frequently following rectal surgery if the surgeon has the necessary experience and performs the operation with great precision. Incidentally, we published this scientific finding as early as 2001 in a renowned surgical journal (Br J Surg).
Leading Medicine Guide: Many patients are unsure what to do after receiving a diagnosis. What do you recommend?
Prof. Dr. med. Christoph A. Maurer: I advise all those affected to seek further clarification at the slightest doubt. No one should hesitate to seek a second opinion – even after treatment has already taken place if the outcome is unsatisfactory.
Leading Medicine Guide: Professor Maurer, thank you for these fascinating insights into the fine art of rectal surgery! We hope that many patients will draw a little courage from this conversation – and the knowledge that it is best to consult a highly experienced specialist. We believe: the success rates mentioned speak for themselves!
This image shows a longitudinal section of the rectum – in the center is the large tumor, appearing dark red, and a smaller secondary tumor can be seen near the lower end of the specimen. The surrounding mesorectal fat is shown in yellow.
