Genitourinary Cancer – 13 – Kidney

Genitourinary Cancer  – 13

(All the articles published in past are available at www.shyamhemoncclinic.com/blog/)
Question: Thank you Chiragbhai for several interesting points about treatment of Metastatic prostate cancer. Especially interesting were the ones about specific palliative care options, never heard before like hemibody irradiation, or radionuclide injection for pain control. Available, easy, and cost effective, but without awareness of such options so many patients suffer. Also referral to palliative care centers which provide free of cost expert care should also be availed so that even poorest of poor need not suffer due to lack of resources.
We have covered prostate cancer extensively. What is the next genitourinary cancer that we will discuss?
Answer: Kidney cancer is the next important one that we need to cover. Ranked 21st in latest 2018 Globocan data for India, there are about 15,500 new cases per year. And about 10,000 deaths per year. Cancers of kidney are peculiar in the sense that they can present in several ways, including some that easily point towards kidney and some very nonspecific. For example, blood in urine, or abdominal pain are likely to lead to this diagnosis easily as abdominal sonography can easily show a kidney mass.
However there are others who present with very nonspecific symptoms like fever, weight loss, fatigue or anemia, and may be treated with vitamins and other general advice. Rare patients present to us for hematological work up of a high Hb with high RBC count (erythrocytosis).
A significant number of patients are now detected incidentally however. During a sonography for other reasons, or routine health check up. Some however present directly with metastatic disease and initial symptoms may be related to the spread, such as bone pain from bone spread.
Que: Interesting. Above data shows that about 40% patients do well in India, even with our late diagnosis in general for most cancers. Compared to many other cancers, this survival data seems better. What are the causes for this cancer? is it tobacco again?
Ans: Well, yes and no. most kidney cancers do not have obvious etiology. But the known risk factors include tobacco smoking, obesity, hypertension.
Rarely related to some hereditary syndromes, such as von Hipple-Lindau. Additional risk factors include acquired or hereditary cystic diseases of kidney; sickle cell trait. Later is associated with a rare type of kidney tumor, medullary carcinoma.
There are several other risk factors studied with little effect or controversial effect, most important being use of pain killers, including aspirin, paracetamol, NSAIDs. Of course, this is applicable to prolonged heavy use, if at all, and not associated with short or occasional exposure.
Que: What about kidney stones?
Ans: This too has been studied with limited quality data, and so far not conclusive. There has been suggestion of small increase in incidence, if at all. Best way to counsel our patients would be to avoid confirming this as a definite risk factor, and advise them to focus on more well known risk factors and things they can otherwise do in general to prevent most common cancers.
Que: Thank you. What are the types of kidney cancer? and how do you diagnose?
Ans: Most common pathology type is Renal cell carcinoma (RCC), about 90%. Out of these, about 80% are Clear cell carcinoma, and 20% are non clear cell histologies. Then there are other rare types like, chromophobe, papillary, translocation, and bellini duct tumors. Transitional cell carcinoma of renal pelvis also presents as a renal mass, though technically not counted as kidney cancer.
Diagnosis is suspected by some kind of imaging, such as ultrasound, often confirmed by CT scan. PET-CT scan has little value, except in case of suspected metastatic disease.
Biopsy is rarely used in localized disease for diagnosis. USG or CT findings are generally diagnostic for malignancy, and nephrectomy (partial or complete) is done based on these findings. Ocassionaly for central tumors, with suspicion for a different histology like transitional cell carcinoma, or lymphoma, a USG/CT guided percutaneous biopsy can be done to establish diagnosis. A chest CT scan, or at least a chest x ray in case of small tumor size, is recommended for staging. Other staging work up depends on symptoms or other signs of metastatic disease.
In case of metastatic disease, biopsy is must before treatment, generally done from metastatic site, such as bone, lung etc. There are no tumor markers, or indirect tests to diagnose kidney cancer.
October 15th 2018.

Dr. Chirag A. Shah; M.D. Oncology/Hematology (USA), 079 26754001. Diplomate American Board of Oncology and Hematology. Ahmedabad. drchiragashah@gmail.com