Surgical Oncology

Surgery plays a central role in the management of most cancers and in most instances is still the only therapy that reliably offers the patient the possibility of cure. However in order to achieve the best possible results all cancers should be treated by a multi-disciplinary team consisting of an experienced surgeon, a radiologist and a oncologist. The following principles are broadly applicable to most cancers.

  1. Screening:
  2. Most cancers grow relatively slowly and may take many months or more likely years to grow large enough to become symptomatic. Presenting symptoms may thus be very subtle and insidious in onset. In order to diagnose cancer early and ensure the best outcome the GP or surgeon needs to have a high index of suspicion or the patient needs to take part in regular screening tests. Screening guidelines for colorectal and breast cancer are well established, but unfortunately not practiced widely.

  3. Diagnosis:
  4. The consequences of a cancer diagnosis can be dire (the emotional burden, the need for major and sometimes disfiguring surgery and treatment with potentially toxic chemotherapy agents). Therefore we need to establish the diagnosis beyond doubt. The best way to do this is to obtain tumour cells (fine needle aspiration) or better still tumour tissue (large core needle biopsy or incisional biopsy). Pathological examination of these specimens will then confirm or exclude the presence of cancer. In some cases a blood test (called a tumour marker) may exist that is very specific for that cancer, i.e. primary liver cancer. In such cases a positive test for the tumour marker might be sufficient to establish the diagnosis. In rare instances the cancer may be in such an inaccessible spot i.e. a tumour in the head of the pancreas that it may be impossible to obtain a reliable tissue diagnosis. In these cases the diagnosis will be presumed based on the patient’s symptoms and the imaging characteristics of the tumour.

  5. Staging:
  6. Once the diagnosis of cancer has been confirmed the cancer needs to be ‘staged’. This refers to appraising to the local extent (and resectability) of the tumour, the extent of lymphatic (‘glandular’) spread and the presence/absence of distant organ spread (metastases). The first 2 objectives can be accomplished with a CT or MRI scan of the area in question. A PET CT, bone scan or chest CT might be necessary to exclude distant organ (metastatic) spread. Determining the stage of the cancer is extremely important as this directs the order and extent of future surgery and oncological treatment and is also an important predictor of prognosis.

  7. Neo-adjuvant treatment
  8. The term ‘neo-adjuvant treatment’ describes the use of chemo- and/or radiotherapy before surgery. There are numerous potential advantages to the use of pre-operative radio-/chemotherapy:

    • systemic treatment (chemotherapy) is given as early as possible in the disease process.
    • the size of the tumour can be decreased and the extent if the resection can potentially be less extreme.
    • the patient may physiologically be in a better state to tolerate the chemotherapy before rather than after a major surgical procedure.
    • the biology or ‘aggressiveness’ of the tumour can be assessed early on by gauging the response to chemotherapy and will have an impact on future treatment and also on predicted prognosis.
  9. Surgery:
  10. Surgery can be done with either curative or palliative intent. If the intention is to cure, the aim of surgery will be to resect all macroscopic tumour and as many lymph nodes that drain the area of the tumour as possible. If the aim is palliation cure is not possible and surgery will be done to treat (palliate) current symptoms or prevent future symptoms / complications. Surgery can be done open or in a minimally invasive manner. The advantages of minimally invasive surgery has been well documented here.

  11. Adjuvant treatment
    • Radiotherapy:
    • Radiotherapy is the use of ionizing radiation to control or kill malignant (cancer) cells. Radiotherapy can be curative in certain forms of cancer if it is localized to a specific area. However, it is mostly used as an adjunct to surgery before (neo-adjuvant) or after (adjuvant) the surgical procedure. The aim would then be to either shrink the tumour (before surgery) or to destroy residual microscopic disease (after surgery) and prevent a local recurrence. Radiotherapy is synergistic with chemotherapy, and is usually used before, during or after chemotherapy in susceptible cancers. Radiotherapy will be overseen by an oncologist who will discuss the treatment an possible side-effects in much more detail prior to beginning treatment.

    • Chemotherapy
    • Chemotherapy is the treatment of cancer with medication that kills cancer cells (also called cytotoxic or anti- neoplastic drugs). These drugs act by killing cells that divide quickly (one of the main properties of most cancer cells). Unfortunately chemotherapy also harms cells that divide rapidly under normal circumstances: cells in the bone marrow, digestive tract, and hair follicles. This results in the most common side-effects of chemotherapy: myelosuppression (decreased production of blood cells, also immunosuppression), mucositis (inflammation of the lining of the digestive tract), and alopecia (hair loss). Chemotherapy can either be administered with the intent to cure (curative) or where cure is not possible it can be administered to prolong and improve quality of life (palliative intent). Chemotherapy will be administered by an oncologist who will discuss the treatment and possible side-effects in much more detail prior to beginning treatment.

    • Immunological therapy:
    • Immunological therapy, also known as targeted therapy or molecularly targeted therapy refers to types of medication that blocks the growth of cancer cells by interfering with specific targeted molecules needed for development and growth of cancers, rather than by simply interfering with all rapidly dividing cells (e.g. with traditional chemotherapy). These drugs are at the forefront of cancer treatment research and are expected to be more effective than current treatments and less harmful to normal cells (i.e. less side-effects).

  12. Follow up:
  13. Once you have completed the full course of cancer treatment (surgery, chemotherapy, radiotherapy and/or immunological therapy) you will be required to come for regular follow-up appointments with your surgeon and/or oncologist (even if you are deemed ‘cured’ or free of cancer). Follow-up investigations such as colonoscopies, mammograms, blood tests, ultrasounds or CT scans will also periodically be necessary. The interval of these visits will be determined by the timespan that you have been cancer free.


Thyroid Cancer

Thyroid cancer is a rare cancer that affects the thyroid gland, a small gland at the base of the neck. The most common presenting symptom of thyroid cancer is a painless lump in the neck. Other symptoms usually indicate more advanced disease and include:

The diagnosis of thyroid cancer depends on a good history, the interpretation of the thyroid function tests (a blood test) and most importantly a fine needle aspiration of the lump to obtain cells for evaluation by a cytopathologist. In the minority of cases surgery might be necessary to confirm or exclude cancer.

There are 4 subtypes of thyroid cancer:

Once cancer has been diagnosed the treatment will consist of surgery followed by radioactive iodine.

Surgery for thyroid cancer will entail either removing half of the thyroid gland (thyroid lobectomy) or all of the thyroid gland (total thyroidectomy). Surgery is done under general anaesthetic and will leave a small scar at the base of the neck. The following complications may occur after a thyroidectomy:

Radioactive iodine treatment: After having thyroid surgery, a course of radioactive iodine treatment may be recommended. This will help destroy any remaining cancer cells in your body and prevent the cancer returning.

Oesophageal (foodpipe/gullet) Cancer

Oesophageal cancer is malignancy of the esophagus. There are 2 main subtypes, squamous cell cancer (accounts for 80 – 90% of all esophageal cancer worldwide) and adenocarcinoma (more prevalent in western societies, related to Gastro Esophageal Reflux Disease (GERD)and obesity; incidence increasing dramatically). Squamous cell cancer arises from the cells that line the upper part of the esophagus. Adenocarcinoma arises from glandular cells that are present at the junction of the esophagus and stomach. Barret’s oesophagus is an important precursor for adenocarcinoma

Esophageal tumors usually lead to symptoms of dysphagia (difficulty swallowing), odynophagia (painful swallowing) and weight loss. With advanced disease hoarseness and coughing after swallowing can also be prominent symptoms. Unfortunately these symptoms usually present quite late in the course of the disease explaining the generally poor prognosis of this disease.

Any suspicion of oesophageal cancer will lead to an upper gastrointestinal endoscopy (gastroscopy) and the diagnosis will be confirmed with biopsy. After appropriate staging examinations (CT chest and abdomen +/- PET CT) an appropriate treatment strategy will be decided on. Small and localized tumors are treated surgically with curative intent. An oesophagectomy is a major procedure with significant risks of complications and even death. Depending on the stage of the cancer it can be done through an abdominal, chest and neck incision or just through a neck and abdominal incision. The stomach is then fashioned into a tube that is used to replace the oesophagus. Chemo-and radiotherapy will be needed before or after surgery to ensure the best possible prognosis.

Tumours that have already spread to distant organs or larger tumors that are inoperable are treated with palliative care; their growth can still be delayed with chemotherapy, radiotherapy or a combination of the two. In some cases chemo- and radiotherapy can render these larger tumors operable. In order to alleviate the symptom of dysphagia a self-expanding metal stent can be placed with the use of a gastroscope.

Prognosis depends on the extent of the disease and other medical problems, but is generally fairly poor.

Stomach (Gastric) Cancer

Stomach cancer, or gastric cancer, refers to cancer arising from any part of the stomach.

Stomach cancer is often either asymptomatic (producing no noticeable symptoms) or it may cause only nonspecific symptoms (symptoms which are not specific to just stomach cancer, but also to other related or unrelated disorders) in its early stages. By the time symptoms occur, the cancer has often reached an advanced stage (see below) and may have also metastasized (spread to other, perhaps distant, parts of the body), which is one of the main reasons for its relatively poor prognosis. Stomach cancer can cause the following signs and symptoms:

The following risk factors for gastric cancer have been identified:

The suspicion of gastric cancer will be raised by the patient’s history and physical findings. The diagnosis will be confirmed by performing a gastroscopy with biopsies of the tumour. Contrast studies (with barium) can also be useful to plan surgery and staging will de done by performing a computerized tomogram (CT) to assess local resectability and exclude metastatic spread (distant disease).

Treatment strategies will be determined by the stage of the disease:

The prognosis of stomach cancer is generally poor. Due to the lack of symptoms in the early stages of the disease, patients often present with a tumour that has already metastasized by the time of discovery. Most people with the condition are also elderly (median age is between 70 and 75 years) at presentation, often with significant co-morbidities.

Gallbladder Cancer

Gallbladder cancer is cancer that begins in the gallbladder. Gallbladder cancer is uncommon. When gallbladder cancer is discovered at its earliest stages, the chance for a cure is very good. But most gallbladder cancers are discovered at a late stage, when the prognosis is often very poor. Gallbladder cancer is difficult to diagnose because it often causes no specific signs or symptoms. Also, the relatively hidden nature of the gallbladder makes it easier for gallbladder cancer to grow without being detected.

Gallbladder cancer signs and symptoms may include:

Most gallbladder carcinomas are diagnosed incidentally when a cholecystectomy is attempted with the presumptive diagnosis of acute cholecystitis. If the diagnosis is suspected before surgery a computerized tomogram (CT scan) will confirm the diagnosis.

Treatment will depend on the stage of the disease. If the cancer is confined to the gallbladder a cholecystectomy (removal of the gallbladder) might be curative. In more advanced disease a local liver resection will be added to the cholecystectomy. Once the cancer has metastasized (spread to distant organs) surgery is no longer of value. Chemotherapy and radiotherapy will be administered to relieve the symptoms of cancer (palliation). If jaundice is present a metal stent can be placed to relieve the jaundice.

Pancreatic Cancer

Pancreatic cancer occurs when cancer develops within the pancreas gland (which is located behind the stomach). Signs and symptoms of pancreatic cancer may include abdominal or back pain, yellow skin (jaundice), unexplained weight loss, light stools, dark urine and loss of appetite. These cancers often produce very little symptoms early in the disease. By the time patients seek help the disease is often found to be inoperable and therefore incurable as results from chemo- and radiotherapy have been disappointing.

Diagnosis is usually based on a combination of imaging tests such as ultrasound, computer tomography (CT), magnetic resonance imaging (MRI); blood tests such as CEA and CA 19-9 and surgical biopsy or fine needle aspiration biopsy (FNAB).

Surgery is still the mainstay of treatment and offers the only realistic chance of cure. If imaging tests indicate that the tumour is resectable and the patient is physiologically fit for major surgery the patient will be offered a resectional procedure in the form of either a panreatico-duodenectomy (Whipple procedure) for a tumour in the head of the pancreas or a distal pancreatectomy with splenectomy for tumours of the body or tail of the pancreas.

Colon Cancer

Colon cancer is a common disease (2nd most common in women and 3rd most common in men). Lifetime risk is in the order of 4-5% and mean age at diagnosis is 69 years.

Risk factors include: diet, obesity, smoking and physical inactivity. Dietary factors that increase the risk include: red and processed meat as well as alcohol. Another risk factor is inflammatory bowel disease, which includes Crohn's disease and ulcerative colitis. Some of the inherited conditions that can cause colorectal cancer include: familial adenomatous polyposis and hereditary non-polyposis colon cancer; however, these represent less than 5% of cases.

Colon cancer typically starts as a polyp (benign tumor or adenoma) which over time (3-8 yrs) becomes cancerous. This “adenoma-carcinoma sequence” provides the rationale for performing screening colonoscopies from the age of 50 years (if no other risk factors present). By removing small benign polyps the risk of developing cancer in the future can be drastically reduced.

The signs and symptoms of colorectal cancer depend on the location of the tumour in the colon and whether it has spread elsewhere in the body (metastasis). Tumours in the right side (beginning) of the colon typically give the least symptoms and are usually more advanced at diagnosis. The classic warning signs include: worsening constipation, blood in the stool, decrease in stool calibre, loss of appetite, loss of weight and nausea or vomiting in someone over 50 years old. While rectal bleeding or anaemia are high-risk features in those over the age of 50, other commonly-described symptoms including weight loss and change in bowel habit are typically only concerning if associated with bleeding.

When a patient presents with complaints suggestive of colon cancer the diagnosis needs to be confirmed with some form of imaging. A barium enema (barium is injected into the colon and X-rays are taken to show the inner lining of the colon) or CT colonography can be done, but by far the most common means of diagnosis is to perform a colonoscopy. A colonoscopy has the advantage the it can diagnose the tumour, remove small polyps or tumours and biopsy the tumour if too large to remove.

Once the diagnosis has been confirmed the tumour needs to be staged. This is done by performing a CT scan of the chest and abdomen. The CT scan will show whether there are distant metastasis and wether the primary tumour is resectable.

If both the above conditions are met the patient will be evaluated for surgery. If the patient has prohibitive medical risks (too ill to operate / will not survive the surgery) surgery will not be performed. In all other cases the patient will undergo a segmental colectomy (removal of the part of the colon that contains the cancer as well as the lymph nodes that drain that area of the colon) with primary anastomosis (the ends of the remaining bowel will be re-joined). These procedures can be done in an open or minimally invasive fashion.

Histological evaluation of the cancer will determine the need for adjuvant chemotherapy. The aim of chemotherapy will be to prevent the appearance of metastatic disease (systemic spread of the cancer) or to treat metastases that are already present. There is good evidence these days that resection of limited / stable liver or lung metastasis can improve the long-term survival in patients with metastatic colon cancer.

The prognosis of colon cancer has improved in recent years due to better chemotherapy agents and earlier detection due to the introduction of screening programs.

Appendix Cancer

Appendix cancer is very rare (0.5% of all gastrointestinal cancers).

Different types of cancer occurring in the appendix include: carcinoid tumours (tumours with the ability to secrete hormones), adenocarcinoma (‘normal’ colon cancer), signet ring cell adenocarcinoma (a very aggressive form of cancer) and lymphoma (cancer of the lymphatic / glandular tissue).

Tumours of the appendix usually present with very non-specific symptoms which make them difficult to diagnose. These symptoms may include: abdominal pain, appendicitis, fluid accumulating in the abdomen, change in stool pattern and infertility in females.

Treatment depends on the size of the tumour, the type of cancer and the presence of metastatic disease. As mentioned before, most of these patient present with advanced disease and a poor prognosis. In these cases surgery will mostly be palliative (aimed at relieving symptoms and not curing the patient). However, if the patient does present early surgery can be curative. In these cases a simple appendectomy (tomour less than 1.5 cm) or a right hemicolectomy (tumour more than 1.5 cm) will be done. Some patients with diffuse intra-abdominal disease might benefit from de-bulking surgery (removing as much visible tumour as possible) and even intra- operative, intra-peritoneal chemotherapy) to try and improve survival.

Prognosis depends on the type of cancer and the presence of metastases (distant spread), but is mostly poor.

Rectum Cancer

Most of what is said under the heading Colon cancer also applies to cancer of the rectum. However there is some important differences that will be highlighted here:

The anatomy of the rectum (last 12 – 15cm of the colon) is such that it is confined to the bony pelvis. This makes it ideal to administer radiotherapy as it is in a fixed position and there are no other sensitive organs close by that will be damaged by the radiotherapy.

The close proximity of the anal sphincters (muscles that ensures continence) makes surgery of the rectum difficult. If the cancer is very close to these muscles they have to be resected and the patient will be left with a permanent stoma / colostomy. By administering radiotherapy pre-operatively the tumour can be reduced in size which theoretically might make it possible to save these muscles.

Patients with rectal cancer will mostly present with symptoms of passing fresh blood per rectum (which might be falsely attributed to piles and lead to a delay in diagnosis) and tenesmus (the feeling that something remains in the rectum after passing a stool).

Once the diagnosis has been confirmed with a colonoscopy and biopsies of the tumour the patient will be staged by performing a CT scan of the chest and abdomen and a MRI scan of the pelvis and/or an endo-anal ultrasound.

The MRI scan will provide valuable information on the position, size and extent of the rectal cancer. Most rectal cancers (except the very early ones) will now be treated with pre-operative (also called neo-adjuvant) radiotherapy. A mild dose of chemotherapy will be added to improve the effectiveness of the radiotherapy. This usually takes 2 - 3 Months to complete.

Once the neo-adjuvant treatment is completed the patient will be re-evaluated for surgery:

For very early tumours it might be possible to perform a transrectal endoscopic microsurgical (TEM) resection of the tumour, thus avoiding major abdominal surgery.

For all other tumours the position of the cancer relative to the anal sphincters will determine what procedure will be done. Whatever procedure is done, the resection of the rectum needs to be done employing the technique of total mesorectal excision (TME). With this technique the whole rectum as well as all the lymphatic tissue that drains it is resected as an intact ‘package’. The introduction of this technique is partly responsible for the recent reduction in local recurrence rates seen after rectal resections.

If the cancer is far enough away from the sphincters the patient will undergo a low anterior resection (LAR).

With this procedure the rectum is resected and the upper (proximal) colon is brought down and joined (anastomosed) to the to the remaining rectum. This anastomosis has a high leak rate with potentially serious complications. In order to avoid these complications an ileostomy (bringing the distal small bowel out as a stoma) might be done as a temporary measure. This stoma will divert stool from the anastomosis and will give it time to heal. It will be reversed in 6 – 12 week’s time. This procedure can be done in an open or minimally invasive manner.

If the sphincters cannot be saved the patient will need a abdomino-perineal resection (APR).

With this procedure the rectum as well as the sphincters are resected. The perineum (bottom) is sutured close and the upper (proximal) colon is brought out onto the skin as a permanent colostomy / stoma. This procedure can be done in an open or minimally invasive manner.

Adjuvant (post-operative) treatment will be necessary in the majority of cases. The need for this will be determined by the pathological (histological) features of the cancer. It may consist of conventional chemotherapy and / or targeted / immunological therapy.

Melanoma

Melanoma is the most lethal form of skin cancer. We as South Africans are particularly at risk because of our good weather and outdoor lifestyle. These cancerous growths develop when DNA damage occurs in skin cells (most often caused by ultraviolet radiation from sun exposure or tanning beds). This triggers genetic mutations that cause the skin cells to multiply rapidly and form malignant tumors. These tumors originate in the pigment-producing melanocytes in the basal layer of the epidermis (the upper layer of the skin) and mostly resemble the appearance of moles. Most melanomas are black or brown, but they can also be pink, red, purple, blue or white.

If melanoma is detected and treated early the chance of cure is excellent. If it is detected after it has spread to other organs it can be very difficult to treat and may be fatal

Risk factors for developing melanoma are as follows:

Melanoma warning signs:

You should examine your skin from head to toe at least once a month to look for any new moles or changes in existing moles. Lesions that itch, bleed or do not heal are also danger signs. The following melanoma characteristics are important to recognize when evaluating moles for the presence of melanomas:

There are 4 recognized types of melanoma:
Three of them occupy the top layers of the skin and only occasionally become invasive, whereas the fourth type is invasive from the start. Invasive melanomas carry a poorer prognosis.

Once the diagnosis of a melanoma is considered it needs to be confirmed / excluded by performing a surgical biopsy. The lesion is excised with a 1mm margin and sent for histological evaluation. The histology will confirm the diagnosis; determine the type of melanoma and the depth of infiltration. Of these factors the depth of infiltration is the most important as this will determine the prognosis to a large extent and will also determine with what size margin the biopsy scar needs to be re-excised. This is necessary to decrease the chance of a local recurrence:

If the tumour is 1mm thick or more the patient also needs a sentinel node biopsy. With this procedure a radio-active substance is injected into the tumour site. The first lymph node that drains the skin of the leg is identified in the groin and removed. If there is cancer in this node all the lymph nodes of the groin area are removed; if it is clear of cancer, no further surgery is done.

Patients with deep primary tumours (>4mm thick) or those with lymphnode positive disease are considered to have a high risk of systemic / recurrant disease and would qualify for some form of adjuvant therapy.

Interferon alfa is approved for adjuvant treatment after excision in patients who are free of disease but are at high risk for recurrence.

Conventional chemotherapy, radiotherapy, granulocyte-macrophage colony-stimulating factor (GM-CSF) and immunotherapy (vemurafenib) all have a role to play in the adjuvant setting.

However, there are currently no standard systemic therapeutic regimens that offer significant prolongation of survival for most patients with metastatic melanoma without significant risk of toxicities.