Renal
Cell Carcinoma; how close are we to successful treatment
Renal cell carcinoma
(RCC) or renal carcinoma (RC) is a disease in which renal cells or kidney cells
become carcinogenic with unregulated growth resulting in tumours. There are
various forms of RCC although the most common type appears in the lining of
tubules within the kidney. Although RCC is not very common amongst the general
population, most of these cancers are found prior to metastasis due to the
treatment being early onset of the disease.
In most cases of kidney
cancer, patients lack symptoms during the initial stages. However, as the tumour
grows larger symptoms such as blood in urine, lumps in the abdomen, extreme
fatigue, anaemia, weight-loss due to unknown reason, temperature, bone pain and
swelling of the ankles or legs may occur. There are several risk factors that
may act as the causative agents of RCC including; smoking, use of pain killers
for lengthy periods of time, obesity, long term dialysis treatment for advance
kidney disease, family history, pre-disposition to genetic conditions such as
Von Hippel-Lindau syndrome or inherited papillary RCC, exposure to chemicals
such as cadmium, asbestos, benzene, herbicides and organic solvents.
Although more
conventional treatments of RC were chemotherapy and surgery for decades, modern
day medicine has changed the face of this form of treatment in the past few
years. Today the treatment of RCC is more advanced and may include conventional
methods in combination with targeted therapy, hormonal and biological
treatments which is mainly decided by a team of specialists known as the MDT
(multi-disciplinary team) which includes an oncologist, urologist, radiologist,
pathologist and specialist nurse. In UK the MDT uses national treatment guidelines
to cater a patient specific form of treatment. The best form of treatment for
most cases of RCC is surgery hence the type of surgery is dependent upon the
size of the tumour. The most common type of surgery is known as a radical
nephrectomy which is the removal of the affected part of the kidney and
surrounding tissue via an incision made between the lower ribs on the side of
the tumour. This may or may not include the removal of lymph nodes close to the
kidney as precautionary measure to prevent the cancer from spreading although
some tissue may be analysed by pathologists to check for existing cancer cells.
Another surgical method is known as partial nephrectomy which is used when the
tumour is less than 4cm in size and includes the removal of the tumour and part
of the surrounding tissue. Laparoscopic surgery is another form of surgery used
to remove a portion or the entire kidney using a small opening through the
abdomen rather than an incision. The Laparoscope is a slim tube with an eye at
one end and a magnifying lens at the other with 3 small cuts in the skin with
the largest being around the navel and is used to remove the kidney. Some
surgeons may also use a robot to help with this form of surgery which is controlled
by the surgeon. The main advantage of this form of surgery is that the recovery
period is less due to the smaller incisions and can also be used amongst those
patients that aren’t physically fit for a full scale operation. It is essential
that patients choose a skilled specialist surgeon in this area if this is the suggested
route by their MDT. In the case of secondary tumours or metastasis RCC it may
be still effective to remove the cancerous kidney to enhance the rest of the
treatment plan. In the case of persistent secondary tumours, surgery is rarely
used to remove them and they may only be removed if it is presented within a
limited area. Removal of this type of region may slow down the growth of the
cancer and control the cancer for longer. Embolisation is a different type of
surgery to block the supply of blood to the tumour if the tumour is too large
to be removed. This method is rarely used but it helps in controlling symptoms
such as bleeding. A catheter or a thin tube is inserted into a blood vessel in
the groin of the patient followed by the use of an X-ray; the surgeon inserts
it into the renal artery which carries blood into the kidney resulting in the
blockage of the blood supply to the tumour leading to the starvation of oxygen
and nutrients that it needs to grow. Cryotherapy or the use of cold
temperatures to destroy cancerous cells is another surgical technique used under
general anaesthesia where one or more probes are inserted into the tumour. A
coolant is passed through the probes which destroys cancer cells within an area
of 1cm. However, this method may cause blockage within the tube that connects
the kidney to the bladder or damage the bowel but side effects in general are
less severe in comparison to other surgical methods. HIFU or high intensity focused
ultrasound is a fairly new surgical method that uses a high energy high
frequency focused sound wave resulting in a high temperature within the tumour
cells leading to their destruction. This is carried out under general
anaesthesia and leads to less severe side effects compared to conventional
surgical methods. RFA or Precutaneous radiofrequency ablation uses heat to
destroy cancerous cells. Patients are given a sedative and a local anaesthesia
to numb the area of interest followed by the production of images by an
ultrasound scanner which indicates the area to be treated. One or more
electrodes are attached through the skin into the centre of the tumour
resulting in heat leading to the death of cancerous cells. To avoid pain and
discomfort upon the completion of any of these types of surgery pain killers
such as morphine are prescribed to patients. Upon the completion of any of
these types of surgery patients will be encouraged to move about as this is an
essential part of the recovery process and in most case a physiotherapist or a
nurse will be assigned to regulate frequent leg movements and deep breathing
exercises.
Radiotherapy is the
most commonly used mode of treatment for RCC or any other type of kidney cancer
which uses high energy X-rays to destroy cancer cells. It’s highly recommended
for those patients that comprise of intensifying pain due to the presence of the
tumour or bone or brain metastasis. Radiotherapy is given in fractions and
general side effects include nausea, vomiting and fatigue which disappear upon
the completion of treatment.
Biological treatments
for this type of cancer include substances which are naturally occurring within
the body including cancer growth inhibitors, interferon, aldesleukin and
monoclonal antibodies. These may be used in the treatment of advance cancer
which is local to a particular region of the kidney. Cancer growth inhibitors such as Sunitinib,
Sorafanib, Temsirolimus and Everolimus may also be given to patients with stage
3 or 4 kidney cancer. Although these drugs are licensed to be used within the
UK, it is not available in some parts of the world. Sunitinib is a
multi-targeted kinase inhibitor which works by the interference with growth
signals of cancer cells and their surrounding blood vessels. It’s given in a
daily tablet form for 4 consecutive weeks with a 2 week period of rest making a
form of cycle treatment. Common side effects of this drug may include
tiredness, hand-foot syndrome, raised blood pressure and rash or thinning of
hair. The drug may also cause hypothyroidism making it less effective. Interferon
is another new form of immunotherapy which is used for the treatment of cancer.
There are many types of interferon and the type used in the treatment of kidney
cancer is known as interferon alpha-2a which is provided intravenously 3 times
a week subcutaneously. Side effects may include chills, high temperature, headaches
and joint/muscle aches. Aldesleukin is another form of immunotherapy and the artificial
version is known as interleukin-2 (IL-2) which also occurs naturally in the body
in response to infection. This method is a complex treatment regime with severe
side effects thus has limited usage. Monoclonal antibody treatment is a
thriving field of excellence not only to treat kidney cancer but also other
forms of cancers. The drug Bevacizumab also known as Avastin is becoming a
popular drug to fight certain forms of kidney cancer as it inhibits the
formation of new blood vessels leading to the starvation of the tumour followed
by its shrinkage or inhibition of its growth. Bevacizumab has been licensed to
treat kidney cancers as part of a combinational treatment with interferon.
However, the treatment isn’t available worldwide.
Targeted treatments
have become a modern day marvel in the field of medicine with its ability to
target specific portions such as proteins, antigens and receptors of specific
cancers. This may be used for patients with stage 3 and 4 kidney cancers which
are either localised or metastasised. This form of therapy causes the reduction
of tumour size or growth. Sunitinib and Sorafanib are 2 key forms of targeted
therapies although they are not available worldwide as yet. Sunitinib has now
become the first choice treatment for RCC and has recently been given the stamp
of approval by NICE (National Institute for Clinical Excellence) which is an
independent organisation which offers guidelines in the treatment of cancer. Sorafanib
may be used for those patients that Interferon-alpha (IFN) or IL-2 isn’t
suitable. This multikinase inhibitor is provided as a daily tablet to prevent
growth of new blood vessels and cancerous cells.
Hormonal treatment may
be offered to some kidney cancer patients in the form of daily progesterone
tablets. Side effects are usually very mild but may cause fluid retention
resulting in the inflammation of feet and ankles.
Despite popular belief
chemotherapy isn’t a good method as some of the other methods mentioned here to
treat any type of kidney cancer. However, it is still being used as a
disruptive agent against the growth and division of cancerous tissue.
Since the birth of new
therapies kidney cancer may become a type of cancer that may be successfully
treated in every patient in the future.
