Successful outcome of a nephron-sparing surgery in a solitary kidney with multiple renal masses
Surgical excision offers the best chance of cancer control in cases of kidney cancers. This can be achieved either by total removal, also known as radical nephrectomy, or by removal of the renal tumor alone while preserving the normally functioning kidney tissue. This latter procedure is known as nephron-sparing surgery or partial nephrectomy. When a person has a single kidney, management of renal cancer poses significant and unique challenges, because preserving the normal functioning kidney becomes an equal priority as is the complete cancer cure. Nephron sparing surgery therefore becomes the only modality in such cases. Removal of multiple tumors in a single kidney is even more challenging as functioning kidney tissue further gets reduced with removal of each tumor. Here is a case in point that proves the effectiveness of partial nephrectomy in providing a better quality of life to patients who have a single kidney with multiple tumors.
How a partial nephrectomy saved a man
A 42-year old gentleman came to us with a diagnosis of renal tumors in a solitary right kidney. This patient was detected to have locally advanced cancer in his other kidney few months before presenting to us, for which his left kidney was surgically removed. Unfortunately, he rapidly developed multiple cancerous tumors in his only remaining right kidney within a few months. Metastatic workup suggested no cancer spread inside the body. Since the tumors were present almost in every pole of this kidney, the best option for curing this patient's cancer would have been total removal of the affected kidney. But removing a single functioning kidney would have resulted in making him dependent on renal replacement therapy in form of dialysis for the rest of his life. So, we planned a partial nephrectomy procedure for him, removing only the tumors (seven in number) saving the maximum possible normal kidney tissue.
During surgery, there were specific challenges.
1. The tumors were scattered everywhere occupying all areas of the kidney - anteriorly, posteriorly, and laterally.
2. The kidney had three renal arteries supplying it, one of which was directly entering into the tumor.
3. One tumor was completely inside the kidney and it was not visible on surface of the organ. For this, we had to employ ultrasonography to locate the site and margin of the tumor during surgery.
4. During this type of surgery, the blood supply of the kidney is temporarily stopped by clamping the blood vessels. But in our effort to save as much kidney tissue as possible, we had to operate as quickly as possible to minimise the ischemic damage due to temporary cutting of the blood supply (We used sterile ice-slush for surface cooling of the kidney to reduce the ischemic damage). At the same time, we were required to be extremely precise in taking out all the seven tumors and while repairing the areas from where those were removed.
The patient successfully underwent nephron-sparing partial nephrectomy. All seven tumors were completely removed and a good mass of functioning renal tissue could be saved.
After the operation, the patient recovered smoothly. His urine output was adequate without any need for hemodialysis, indicating a good functioning kidney. The patient's creatinine (marker of kidney function) did rise after surgery but rapidly came down in a few days. At the time of his discharge from the hospital, his creatinine was 1.7 mg/dl. During his follow ups, his creatinine came down further (1.2 mg/dl) and completely normalized within the next few days. The patient resumed back to his normal work within a few days after discharge. He did not have any complications or the need for re-intervention.
Key Learnings
Normal kidney function depends on the number of healthy nephrons, the functional units of kidney. In research, it has been found that decreased renal filtration capability (because of loss of nephrons) was independently associated with increased risk of death. In patients with a single kidney, preservation of renal parenchyma is of paramount importance, as life expectancy is decreased fourfold in those on hemodialysis as compared to healthy subjects. The quality of life also gets impaired significantly in such situations. In cases with multiple tumors in a single kidney, large number of normal nephrons may be lost while removing the tumors as they get removed in small rims of normal tissues along with the tumors. If not, then a part of cancer may be left behind which can regrow in the future, which is also an undesirable outcome.
Decision making in such cases is challenging as the surgical and oncological risks of nephron-sparing surgery must be weighed against the morbidity and mortality with hemodialysis and renal transplantation if the kidney is removed.
This case was unique as the patient underwent multiple tumor removal and still had a good functioning renal tissue. The patient is now living normal cancer-free and dialysis-free life. To our knowledge, this is one of the very few cases reported in the world literature and the first such case reported in India.
