Hi Clyde,
First, the was a typo. The basement membrane is thin, not thick.
I was the opposite. The CT scan for my bladder cancer showed an enlarged prostate. A year later my urologist
did the first TURBT, he did TURP. It was benign. Now I can go for a 2 hrs walk with my puppy without my looking for the bush to hide. My GP was prescribing Flowmax and did not think of sending me to a urologist. I did not know about bladder cancer. Neither I knew the anatomy of the bladder or its location back then. It was good that you found the tumor early.
Progression of CIS
Data show that CIS without treatment has a high probability to progress. A case in point is the study I referenced
in the previous post said about 50% of CIS cases had recurrence or progression even with intravesical chemotherapy. The report does not say how many of 50% had recurrences or progression. Also, the report does not say how many of those recurred was CIS or TaLG. But, considering the current recommended treatment of CIS with recurrence of CIS is radical cystectomy, AUA must be thinking that CIS has a tendency to progress.
Progression of CIS after BCG treatment
A large study was done by the same group in 2002 on the progression of papillary type and CUS after BCG treatment says that based on a median followup of 2.5 years and a maximum of 15 years, the percent of patients with progression was low (6.4% of 2,880 patients with papillary tumors and 13.9% of 403 patients with carcinoma in situ). It means 86% of CIS after BCG therapy did not progress.
BCG unresponsive treatment
Suppose your CIS did not respond to BCG as the other 86% of patients.
You will have a choice of bladder salvage treatment or radical cystectomy and live with a new norm.
If you choose for bladder salvage, it is important first, your hospital follows a certain protocol to
determine if your CIS is truly BCG unresponsive or not. Dr. Ashish Kamat of MD Anderson often states
that how BCG therapies are done is inconsistent among hospitals and urologists. He suggests not
consider BCG unresponsive if a recurrence happens after 6 weeks induction course, but continue at least
do one maintenance course after 3 months. In this context, Dr. Stephan Boorjian of Mayo Clinic explains that BCG-unresponsive NMIBC is defined as persistent/recurrent high-grade Ta or T1 urothelial carcinoma within 6 months of completion of an adequate quantity of BCG or persistent/recurrent carcinoma in situ (CIS) (±Ta or T1 disease) within 12 months of completing an adequate course of BCG. Adequate BCG was considered to be 5 of 6 instillations of induction BCG and 2 of 3 maintenance treatments or 2 of 6 courses of the second round of induction. The only exception was patients who presented with high-grade T1 disease at their first evaluation after induction BCG.
What if your CIS became truly BCG unresponsive and you want to choose bladder salvage treatment?
There are ample of new treatments, including immunotherapy, which you can discuss with your urologist.
Dr. Peter Black of professor of UBC/Vancouver General listed it as follows.
Comparison Across Trials: CR in BCG-Unresponsive CIS
Pembro 102 40% 30% 21% ASCO 2019
ALT-803-BCG 11 82% 64% = AUA 2019
Vicinium 66 40% 28% 17% Sesen Business Update Nov 2019
r-AfIFN2a 103 53% 41% 24% SUO 2019
CG0700 45 - 50% 28% Packiam AUA 2018
I think they are listed # of cases, the complete response at 3 months, 1 year, and 2 years.
Also, there are other treatments like Gemstabine + Docetaxel (heated or unheated) with good efficacy.
I am sure there will be more options if and when your CIC becomes BCG unresponsive though the probability seems to be very low by reading the studies.
How fast bladder cancer grow?
I do not know either. I read somewhere it takes years. But, when I attended a patients education seminar, a speaker/urologist said he was very surprised to see cancer came back just 3 months after the cystoscopy of one of his patients.
If you can take it as just an entertainment, below is my attempt to estimate how fast bladder cancer can grow.
An epithelial cell of bladder is cuboidal with 10-20 micro meter (0.010 millimeter) long. A grain of table salt can contain 8,000 bladder cancer cells. It takes about 24 hours for our cell to divide into two cells. Normal cells only divide until they detect external signals which tell the cells to divide. Normal bladder cells divide every 40 days.
One of the hallmarks of cancer cells is that they do not stop dividing. So, 1 cancer cell becomes 2 in one day and 4 in two days, and 10,000 by 20 days. Technically speaking in perfect condition, a bladder cancer call grows to the size of a grain of salt in just 20 days. In reality, not that fast. I read also that cancer cannot grow more than the size of a grain of salt without getting the nutrition and oxygen from the blood. It will require a process called angiogenesis, in which new blood vessels are created to feed the cancer cells. Incidentally, the MERCK website says that we see blood in urine when the new blood vessels break due to contraction and expansion of the bladder. I do not know how long it will take for new blood vessels to grow to feed bladder cancer cells. There are also genes that influence
the creating of the new blood vessels, but I have not looked into it yet. Still, cancer cells need to compete for resources with normal cells and among themselves, and that might affect too.