Advanced Disease

Epithelial ovarian cancer cells commonly spread in a clockwise pattern from the original site to neighbouring organs through the lymphatic channels and through the peritoneal cavity. This pattern of cancer cell dissemination is thought to follow the motions of the diaphragm and the normal wave movements of the bowels. Complications arising from advanced ovarian cancer tend to be concentrated in this area of the body and include malignant ascites, bowel obstruction and cachexia.

These conditions require the attention of a medical professional and can be life threatening:

1. Ascites or malignant ascites is an accumulation of fluid in the abdominal cavity caused by an imbalance of plasma flow into and out of the blood vessels and the lymphatic vessels. Cancer cells infiltrating the abdomen are the primary cause of this imbalance in women with ovarian cancer. Ascites is detected by a noticeable abdominal swelling, swelling of the ankles, abdominal pain, vomiting, nausea, early fullness, heartburn and anorexia. It is confirmed by a CT scan, MRI and protein blood tests.

Ascites buildup is extremely uncomfortable and can be relieved by draining the fluid using a procedure called paracentesis. After the area is frozen, a needle is inserted into the abdomen at an optimal point determined by an ultrasound. It is connected to a bottle under vacuum and the fluid flows readily. A healthy person has approximately 50-100ml of fluid in the peritoneal cavity. Advanced cancer can result in producing 10 or more litres of fluid. Although the patient feels immediate relief from this drainage, the effect seldom lasts more than two weeks.

A day surgery procedure is available in certain cases of refractory (non-responsive) malignant ascites, whereby a catheter is permanently inserted into the abdomen allowing for drainage at home. This is extremely helpful in freeing up hospital resources and more importantly, putting symptom control in the hands of the patient.

Patients can also be offered diuretics to ease symptoms. They are encouraged to wear supportive stockings, keep their feet elevated and eat small meals frequently.

The only lasting resolution of malignant ascites comes from effective chemotherapy.

As a note of interest, new studies and tests are underway to provide improved methods of treatment including the use of a diphtheria toxin and so-called monoclonal and trifunctional antibodies. Large Phase II clinical trials are underway.

2. Bowel obstruction is a very well recognized complication of advanced ovarian cancer. It can be caused by tumour growth on a specific site on the large or small bowel, it can be the result of surgical adhesions constricting the bowel, it can result from multi-sited cancer "seeds" causing pressure on the colon, and it can be caused by a twist in the bowel or feces compaction. Bowel obstruction can be complete or partial. Bowel obstruction usually causes extreme pain - some report 9 out of 10 on the pain scale. Other symptoms of bowel obstruction include abdominal swelling, vomiting, constipation, lack of flatulence and dehydration. A CT scan and X-rays are used to confirm the diagnosis and hospitalization is generally required.

Treatment of a bowel obstruction is based on the nature of the obstruction, the stage of the patient's disease and their overall medical condition. Conservative management is usually the first course of action including the insertion of a nasogastric tube to decompress the gut, an IV for dehydration and opioids for pain relief. Steroids can be used to reduce inflammation in both the bowel and peritoneal cavity as well as antispasmodics in calming the bowel. Drugs may also be given to reduce secretions into the gut causing significant improvement in nausea and vomiting. If the bowel is only partially obstructed and cramping is not an issue, drugs to increase bowel motility may be introduced.

Bowel obstruction can go from partial to complete and back. Bowel obstruction caused by tumour encroachment can only be resolved with effective chemotherapy or surgery - after which successful management of an obstruction requires the patient to attempt to re-introduce food first on a liquid basis, then a semi-solid low fiber basis and then ultimately returning to a normal diet.

In many cases however, the obstruction is not operable; the patient cannot withstand the surgery or possibly refuses surgery. More commonly, the patient may no longer be a candidate for chemotherapeutic intervention. Unfortunately, this condition and its side effects are the leading failure in patients with ovarian cancer.

3. Cachexia or muscle wasting syndrome is associated with advanced cancer progression. Researchers formerly believed that cachexia was a result of cancer's increased metabolic demand or stolen protein, that it produced toxins and suppressed the appetite.

It is actually a metabolic state in which a "breaking down" instead of a "building up" of bodily tissues happens no matter how much nutritional intake occurs.

Cachexia results in a significant loss of muscle mass, body fat and skeletal tissue. The simple criteria for identifying this syndrome is a greater than 5% loss of body weight over a period of 2 months along with the patient's and oncologist's recognition of the need for the patient to gain weight.

Patients are given appetite stimulants, corticosteroids, antinausea drugs and pain control however none of these remedies last for any length of time. Studies were done on parenteral feeding (by IV) but results were disappointing.

Severe weight loss results in the patient's very poor ability to tolerate treatment interventions and their accompanying toxicities. Several clinical trials are underway including a trial that combines resistance training and aerobic exercise with nutrient and pharmacological intervention. Click on this link for more details:

This is also an extremely informative site on cachexia and supplementation recommendations:

http://www.lef.org/protocols/prtcl-029.shtml

4. Gastoenterological Feeding Options: Depending on the stage of disease progression, multiple feeding options are available to the patient who is unable to consume food orally.  Conditions which preclude eating normally include severe nausea and vomiting caused by ascites, proximal tumours and bowel obstruction.  In most cases, support should be initiated one to two weeks without nutritional intake.  All three of these options require daily homecare nursing and are listed in order of preference, safety and by the advancement of the disease:

1. Enteral Feeding – requires a tube to be inserted through the abdomen, into the stomach and ending in the small intestine.  By inserting the tube further into the digestive tract, it can avoid nausea and vomiting but is not always successful depending on the volume and location of the ascites.  The patient is encouraged to rest at a 45 degree angle during feeding. 
   The insertion is usually performed under local anesthesia by a radiologist.  Complications could arise if the tube has to pass through ascites interference or if there is actual mechanical obstruction.  This procedure is relatively common with feeding easily managed at home.  If the patient is suffering from partial bowel obstruction, a low fiber formula can be given.  Otherwise, the formula is developed on a per patient basis to maximize nutrition and bowel regularity.  Enteral feeding is the only method of gaining nutrition recommended for periods of more than 30 days.
2. Nasogastric Feeding – the tube in inserted through the nose, into the stomach and on into the small intestine.  It avoids any involvement of ascites or tumour interference but is more uncomfortable.  It too is easily managed at home with various formulas depending on the patient’s needs.  Complications with this method include tube dislodgement, clogging and nasal trauma, to name a few.
3. TPN (Total Parenteral Nutrition) line or PICC (Peripherally Inserted Central Catheter) line – is inserted into a vein either in the neck region (TPN) or in the arm (PICC) and then advanced until it reaches a large vein above the heart.  More complications arise with these two methods because of the risk of infection, occlusion (blockage) and possible blood clots.  Once again, special formulas are developed based on the patient’s needs and stage of disease progression.

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