Archive for June, 2013

Kidney Cancer (“Renal Cell Carcinoma”) Part II

June 29, 2013

Andrew Siegel, MD  Blog #110

This blog is dedicated to my friend Shira Litvin, host and producer of “Best In Health Radio” (www.BestInHealthRadio.com), who recognized the critical importance of this disease and prodded/begged/nagged/coerced me to address this subject.

(Continued from last week)

Conventional urological teaching is that a solid mass in the kidney is a cancer until proven otherwise. However, not all solid kidney masses are cancers. It is possible to have a kidney tumor that is benign, e.g., an “oncocytoma” or an “angiomyolipoma.” Kidney cancer needs to be distinguished from the much more common kidney cyst.   A kidney cyst is a sac containing fluid that is within the kidney or attached to the kidney. They are very common, occurring in about 50% of adults over 50 years of age and can be quite variable in size. Most have the appearance of water balloons, are benign, and rarely evolve into a problem.  A simple cyst has a thin wall and no subdivisions (referred to as “septa”), calcifications, or solid components.   If a cyst has septa, calcifications, or wall thickening, it is known as a “complex” cyst and generally needs to followed carefully and regularly and perhaps operated upon.   On occasion, a kidney cancer can be a malignant cystic mass, although most kidney cancers are solid (containing tissue) as opposed to kidney cysts (containing fluid).

Most kidney cancers occur on the basis of sporadic mutations in kidney cells during the process of cellular replication. Cancer begins when kidney cells acquire mutations in their DNA. The mutations direct the cells to grow and divide rapidly and in unchecked fashion, with the accumulating abnormal cells forming a mass.  Ultimately, these cells can extend beyond the kidney and some cells can break off and spread (metastasize) to remote parts of the body, including the bones, chest, liver and brain. Tobacco and obesity have been established as environmental risk factors for kidney cancer.

There are genetic/familial forms of kidney cancer including von-Hippel-Lindau disease and familial papillary renal cell carcinoma.    In general, hereditary forms of kidney cancer occur at an earlier age than those that occur on the basis of mutations.  Furthermore, with the hereditary forms of kidney cancer, it is not uncommon to have multiple kidney tumors present, sometimes present in both kidneys. Certain populations are particularly high risk for kidney cancer.  People with end-stage-kidney disease (renal failure) who are on dialysis are in this group as are those with familial/hereditary kidney cancer.  Those with tuberous sclerosis have a propensity for developing kidney cancers.

Many kidney tumors have a very rich blood supply. Interestingly, some kidney cancers can give rise to a strange set of symptoms known as “paraneoplastic syndromes,” in which symptoms remote from the kidney occur, making the diagnosis confusing.  These syndromes can be high blood pressure; anemia; high red blood cell count; high calcium levels in the blood; elevated liver function tests; fever; etc.

Kidney cancers are commonly referred to as renal cell carcinomas-RCC. They can be “staged” to demonstrate the extent of the disease by using imaging studies including CT or MRI. Stage I means confined within the capsule of the kidney; Stage II invades the fatty envelope surrounding the kidney; Stage III involves the lymph nodes in the region; Stage IV is distant spread of tumor.  Prognostic factors include stage, size, nuclear grade (a description based on how abnormal the tumor cells and the tumor tissue look under a microscope), and histological sub-type of cancer.  In general, the lower the stage, the smaller the size, the lower the grade all portend a better prognosis.

In terms of sub-types of kidney cancer, clear cell RCC is the most common form, accounting for about 70% of those with renal cell carcinoma.  When seen under a microscope, the cells that make up clear cell renal cell carcinoma look very pale or clear. Papillary RCC is the second most common subtype.  These cancers form little finger-like projections (papillae). Pathologists refer to this as chromophilic because the cells take up certain dyes and appear pink under the microscope. Chromophobe RCC accounts for about 5% of kidney cancers.  The cells of these cancers are also pale, but are much larger, and this particular kind of kidney cancer has the best prognosis.

The treatment of early, localized kidney cancer is surgical.  Years ago, this meant complete removal of the kidney.  This is still the case with a large cancer or a central one that affects the key blood supply, but in many cases it is possible to do a “partial” nephrectomy and spare kidney tissue.  Nowadays, this is often done using laparoscopy with robot assistance.  Not all kidney masses need to be removed as some can be observed and if they do not change in size or character over time, it is unlikely malignant.  Thermal ablative therapies are also possible for smaller kidney masses—using either heat (radiofrequency waves) or cold (cryosurgery) placed directly into the mass via CT guidance.  It is often possible to biopsy the mass prior to the ablative therapy using a fine needle via CT guidance.  Kidney tumors in general respond poorly to radiation therapy and chemotherapy, but there are numerous effective alternative therapies for advanced disease including immunotherapy including and targeted therapies.  

Targeted therapies are drugs that interfere with the growth of cancer cells at a molecular level.  These drugs interfere with cell growth, prevent cell replication, or disrupt the blood supply to the cancer cells. Sorafenib and Sunitinib disrupt the blood supply, depriving the tumor of oxygen and nutrients; Temsirolimus and Everolimus block blood supply as well as interfere with cell growth; Pazopanib and Axitinib are additional targeted medications.

Bottom Line: What to do to try to minimize risk and make an early diagnosis of kidney cancer?

·      Stay fit and healthy by eating well and exercising regularly

·      Avoid tobacco

·      Avoid obesity

·      Avoid kidney failure (renal failure) as kidney cancer is much more prevalent in patients on dialysis.  The two leading causes of kidney failure are diabetes and high blood pressure, often but not exclusively on the basis of poor lifestyle choices. Diabetes and high blood pressure frequently respond well to a lifestyle “angioplasty” including weight loss, exercise and healthy eating habits.  If they do not respond to lifestyle optimization, they can most often be managed well with medications.

·      Don’t ignore symptoms that persist and are not normal for you: blood in the urine; flank pain; etc.

·      Although controversial, a non-invasive screening sonogram (ultrasound) of the abdomen can easily pick up an early kidney tumor as well as a host of other problems (liver, gallbladder, spleen, pancreas, aorta, bladder, prostate, ovaries, uterus).  Although it may not be cost-effective for a population at large, if it is you or a loved one who has a potential serious problem picked up, then it is certainly more than cost-effective!

Andrew Siegel, M.D.

Author of Promiscuous Eating: Understanding and Ending Our Self-Destructive Relationship with Food: www.promiscuouseating.com

Available on Amazon in paperback or Kindle edition

Blog subscription: A new blog is posted every week.   On the lower right margin you can enter your email address to subscribe to the blog and receive notifications of new posts in your inbox.  Please avail yourself of these educational materials and share them with your friends and family.

Kidney Cancer (“Renal Cell Carcinoma”) Part I

June 22, 2013

Andrew Siegel, MD  Blog #109

This blog is dedicated to my friend Shira Litvin, host and producer of “Best In Health Radio” (www.BestInHealthRadio.com), who recognized the critical importance of this disease and prodded/begged/nagged/coerced me to address this subject.

My field in medicine is Urology. In addition to being physicians, urologists are also surgeons who care for very serious and potentially life-threatening illnesses, particularly cancers of the genital and urinary tracts. In terms of new cancer cases per year in American men, prostate cancer is number one, accounting for almost 30% of cases; bladder cancer is number four, accounting for 6% of cases; and kidney and renal pelvic (the inner part of the kidney that collects the urine) cancer are number 6, accounting for 5% of cases.  In terms of new cancer cases per year in American women, kidney and renal pelvic cancer are number nine and bladder cancer is in the top 15.  The bottom line is that urinary and genital tract cancers are incredibly common, particularly in men.

Let me begin with an anecdote about a friend of mine who is a plastic surgeon.

I am indebted to him for doing reconstructive surgery on my wife and for being a significant source of comfort and strength during a very difficult time in my family’s life:

When he turned forty, he called me to inquire about urological health, specifically for advice on what actions he should take on a preventive basis. I mentioned a digital rectal exam and PSA blood test to screen for prostate issues, urine analysis, and also told him that almost all of the kidney tumors that we currently diagnose are incidental findings discovered by ultrasound, computerized tomography scan, or magnetic resonance imaging study done for another reason. Based upon this, I suggested that he might want to consider an ultrasound, since it is non-invasive, painless, and without the need for a needle, contrast, or radiation involved with the other types of diagnostic imaging tests. However, he did not proceed with an imaging study at that time and did not broach the subject again.

Fast forward to a year or so later.  For my upcoming 50th birthday, he generously treated me to an all-expenses paid gift of an upcoming intensive 200-mile bike trip from Canada to Massachusetts that would traverse the entire state of Vermont, with an overnight stay in a country inn. He, myself, and a few other friends had been training rigorously for the 100-mile-per-day effort. Several days before our scheduled departure, he telephoned me from our hospital’s imaging center, where he had decided to have a computerized tomogram (CAT) of his abdomen, a step up in terms of providing anatomical information from the ultrasound that I had suggested a year earlier. His decision had been somewhat impromptu—he was experiencing NO symptoms of any kind at all.

I was astonished to learn that he had an 8-centimeter mass in his kidney. I told him that it was likely a benign cyst, but he replied that, no, it was a solid mass and he wanted it removed ASAP.  I was in total shock, I believe almost as much as he was, as I had initially been the one to suggest an abdominal scan. However, NEVER had I imagined that something would actually be uncovered. A follow-up magnetic resonance imaging (MRI) scan showed that this mass appeared to be contained within the kidney and that fortunately there was no evidence of disease spread.

We cancelled the cycling trip and instead arranged for a trip to the operating room. I performed an uneventful nephrectomy (kidney removal), after which he stayed in the hospital for only two days, having an extremely rapid convalescence because he was in such great physical shape. The pathology report confirmed kidney cancer, with no evidence of extension beyond the kidney and a specific kind of cancer that generally augured an excellent prognosis. Believe it or not, he was back on the bike one week after his surgery— an incredibly rapid return to activity. Happily, today he is fine—his follow-up CAT scans have been perfectly normal—and I have every expectation that he will continue to thrive.

The moral of this story is that there are some really good diagnostic tests out there that can pick up certain disease processes in their early and curative phases, obviously really making a difference. The other moral of the story is that his being in such great physical shape and having such a tremendously positive attitude went a long way in helping him recover so rapidly. So, yet another reason to exercise, eat properly, and maintain a healthy lifestyle is the advantages that accrue when you get sick and you need medical or surgical treatment.

There are lots of euphemisms for cancers: “mass”; “tumor”; “lesion”; “carcinoma”; “malignancy”; “neoplasm.” Mass infers the presence of something that should not be there.  A tumor is a growth that can be either malignant or benign.  A lesion is an undefined irregularity.  A carcinoma is a malignant tumor and many kidney cancers are referred to by the term “renal cell carcinoma.”  A malignancy is a malignant tumor.  A neoplasm is a new, abnormal growth of tissue.

Kidney cancer is a very important cancer because it is the most lethal of all urological cancers. The National Institute of Health estimates 65,000 new cases of kidney cancer and 13,500 deaths from the disease for 2013. Kidney cancer occurs more commonly in men than in women, typically in their 50s and 60s.  Kidney cancers needs to be distinguished from cancers of the “renal pelvis,” since although both technically originate in the kidney, they come from distinct regions of the kidney that are very different and the tumors are vastly different under the microscope and have dissimilar patterns of behavior. A classic kidney cancer occurs in the parenchyma of the kidney, the “meat” of the kidney that functions to produce urine. This is as opposed to renal pelvic tumors, which occur in the inner portion of the kidney that collects the urine and is in continuity with the tube system (ureter) that connects the kidney to the bladder.

The kidney is an organ that is tucked deep in the recesses of the body, is enveloped in a very generous fatty pad, and is well protected by skeletal muscle and ribs.   For these reasons, a kidney tumor has to get rather large before it becomes symptomatic, and nowadays, up to 90% of kidney tumors are picked up “incidentally” when imaging studies are done for other reasons, typically an ultrasound, CAT scan, or MRI.   In other words, a patient has no symptoms whatsoever, but gets an ultrasound for an unrelated diagnosis, e.g., right abdominal pain and is found to have a left kidney tumor.  It is most unusual to find a patient with the “classic triad” of symptoms of a kidney tumor: flank pain; blood in the urine; and a mass that can be felt on examination.  If one has the classic triad, one undoubtedly has a large kidney tumor, which is likely malignant. In general, it is desirable to pick up tumors in their earliest phases when confined to their organ of origin as opposed to later on in the course of the disease when they are large or there might be regional or distant spread.  When tumors are picked up incidentally as opposed to being diagnosed on the basis of symptoms, they are generally picked up in an earlier stage of their natural history.

Incidental kidney tumors can often be quite small (referred to as a “small renal mass”—“SRM”) and often deemed “indeterminate” by radiologists, meaning that they are so small that they are difficult to characterize.  These can be managed by following them with imaging studies over time to see if they change with respect to size and character.  CT-directed biopsy can be useful to identify if a mass is benign or malignant and help to select less invasive treatment options if an indolent (slower growing) kidney tumor subtype is identified.

…to be continued next week.

Andrew Siegel, M.D.

Author of Promiscuous Eating: Understanding and Ending Our Self-Destructive Relationship with Food: www.promiscuouseating.com

Available on Amazon in paperback or Kindle edition

Blog subscription: A new blog is posted every week.   On the lower right margin you can enter your email address to subscribe to the blog and receive notifications of new posts in your inbox.  Please avail yourself of these educational materials and share them with your friends and family