Mets Day 501 - PET scan positive for distant mets

Dr. Apolo called me a little while ago with the results of last Wednesday's PET scan.  She said that the lymph node under my left clavicle that had shown up in my August 6 CT scan was "hot", strongly suggesting that I had a distant metastasis of my cancer.  She couldn't be 100% sure until the node could be biopsied, however.  She already had consulted with one interventional radiologist at NIH, who said that my node was too small and too difficult to access to permit a biopsy at this point.  Dr. Apolo said that she was going to consult with the chief of interventional radiology tomorrow to see if he would be willing to try to do a biopsy.  She said that she would call me tomorrow with an update.

So this is bad news, although it was not unexpected.  After my three consultations in the past couple of weeks, I had come to the conclusion that I probably had distant metastatic activity.  I didn't feel a lot of surprise or shock at the news.  I think Jennifer took it a bit harder.  She's decided to put her master's degree work on hold indefinitely.  

Because Dr. Apolo tacitly acknowledged that this scan could be a false positive, I did a bit of reading about PET scans and the chance that my scan was a false positive.  The May 2007 report of the National Comprehensive Cancer Network (NCCN) on PET and CT scans in detecting cancer is here, and suggests that, although PET scans are very good at detecting small amounts of distant metastatic activity, there is about a 10% risk of a false positive.  The NCCN report explained that PET scans are very good at detecting metabolic activity where it does not belong. Cancer cells often have high metabolic activity since they are growing more rapidly than they should.  The patient is injected with a sugar molecule containing radioactive Fluorine called 18-Fluorodeoxyglucose or 18-FDG. A PET scan can see cells that are consuming that sugar for energy. The PET scan detects where the radiation is accumulated in the body, and the radiologist looks for abnormal metabolic activity (such as lymph nodes) in places where it does not belong.  But sometimes - either due to some weird activity in the body, or an interpretive mistake, a false positive reading can be made.

This December 2011 article discusses causes and imaging features of false positives and false negatives on 18-FDG PET and CT scans in oncologic imaging. It discusses various reasons why there might be false readings, none of which seem to be present in my case.  (This 2010 post on Livestrong.com also discusses possible reasons for a false positive PET scan, none of which appear to be applicable to me.)  The 2011 article says that false positives can be minimized if a PET scan and a CT scan both suggest that a lymph node has metastatic activity.  Because I have already had a CT scan showing an enlarged lymph node in the same location, it seems that the likelihood that both scans were falsely positive is very unlikely.  

Thus, the odds are high that I have distant metastatic activity.  In my blog entry of May 29, 2012, I summarized my meeting that day with Dr. Apolo, in which we discussed distant metastatic cancer at length.  The most relevant points remain equally true today:

• There is no known cure for Stage IV bladder cancer.  Nothing has been clinically shown to be effective as a cure, including any type of chemotherapy, immunutherapy, radiation treatments, diet, or whatever.  Anyone who says otherwise is ignoring the facts.  
• The research today is focused on trying to slow the pace of the cancer.  Even a few months of additional time is considered a success.  Each advance builds on past advances, and is how other cancers have eventually found effective long-term treatments.  
• Historically, 90% of all Stage IV bladder cancer patients die within 5 years of the Stage IV diagnosis.  The 10% who survive do so because, for reasons unknown, the cancer does not develop in a distant location.  
• Virtually every bladder cancer patient who has distant metastases develop will die from it.  The average (mean) duration from diagnosis of the distant metastasis to death is about 12 months.

A December 2011 article says "metastatic urothelial carcinoma portends a very poor long-term prognosis, with 5-year survival at approximately 5%. The overall survival of metastatic bladder cancer has not improved over the last 20 years."  A September 2012 article adds that "the prognosis of patients with metastatic disease is still poor with median survival being approximately 12-14 months . . . . No major advances have been achieved in the recent years in the treatment of urothelial carcinoma of the bladder. . . . Several targeted agents are currently under investigation, but no major breakthroughs have been achieved with these drugs."

So what's in store for me?  This National Cancer Institute fact sheet is a good overview of metastatic cancer.  This comprehensive blcwebcafe.org article details the typical course of metastatic bladder cancer, with the the most likely locations for distant metastatic tumors occurring in the liver, lungs, bones, and brain.  The bone metastases can cause intense pain; the others are not as painful.  Eventually, the organs fail, causing death.  There are targeted experimental treatments to slow the growth of tumors in these distant locations, but the quality of life can be degraded by the treatment.  In the coming months, I'll be grappling with those trade-offs. 

Enough data.  Enough typing.  I'm going to go hug my wife.