The Palpable Prostate

Prostate cancer topics, links and more. Now at 100+ posts!

News: Health Day, Medical News Today, ScienceDaily, Urol Times, Urotoday, Zero Cancer Papers: Pubmed (all), Pubmed (Free only), Amedeo
Journals: Eur Urol, J Urol, JCO, The Prostate Others Pubmed Central Journals (Free): Adv Urol, BMC Urol, J Endourol, Kor J Urol, Rev Urol, Ther Adv Urol, Urol Ann
Reviews: Cochrane Summaries, PC Infolink Newsletters: PCRI, US Too General Medical Reviews: f1000, Health News Review

Saturday, February 28, 2015

Extrapolating the increase in prostate cancer diagnoses

"prostate cancer cases increased by 54% between 1975 and 2010, but mortality declined by 30% over the same period." [link]

Focusing on the increasing number of men diagnosed, "Our earliest data point comes from 1973. Back then, 1 man in 16 could expect to be diagnosed with the disease. Between 1973 and 2013, 38 available data points document the increase in the reported incidence of prostate cancer over 40 years." [link] The current proportion is 1 in 6 or 1 in 5. This proportion seems to be increasing linearly with time and based on linear extrapolation half of all men will be diagnosed with prostate cancer by 2124 (110 years from now). See this [figure] illustrating the extrapolated regression cursve.

Sunday, February 1, 2015


[Updated March 15, 2015] The AICR/WCRF report on nutrition and cancer does point out that "Restriction of energy intake from food is the most effective single intervention for preventing cancer in experimental animals."

Unfortunately, the evidence for the anti-cancer effet of fasting is mostly based on animal studies or in human studies with significant limitations. Furthermore, not all the evidence is positive and there have been some negative results such as this study which found no benefit to fasting twice a week in mice injected with prostate cancer cells:
[PMID: 20733612]

Dr. Yu offers the opinion that fasting may be more useful in conjunction with other methods than by itself. [Youtube video]

A survey paper on fasting and cancer in animal studies is available here: [PMC4263749].

Some ways fasting might be carried out are:

- continuous calorie restriction.  Reduce the number of calories eaten each day.

- daily intermittent fasting.  Only eat within a prescribed time window every
  day.  This diet is described in the Fast 5 diet on the [Fast 5 web site] and
  in the free downloadable ebook on that site. It discusses fasting for 19
  continuous hours and eating only within the remaining 5 hours each day.
  [Fast 5 web site]
  [Fast 5 ebook]
  [Fast 5 discussion]
A recent experiment on fruit flies supports this idea finding that fruit flies who were restricted to eat within a 12 hour window each day had superior cardiac health than fruit flies allowed to eat any time they wished. See [PMID: 25766238] and [San Diego University news release].
- Alternate Day Fasting.  Every other day reduce calories to 25% of normal.

- weekly intermittent fasting.  On the 5:2 diet one eats normally 5
  days a week and reduces calories to 25% of normal on 2 non-consecutive
  days a week.  The diet is described in the book Michael Mosley, The Fast
  Diet: Lose Weight, Stay Healthy, and Live Longer.

- monthly intermittent fasting.  Dr. Vatter Longo has been experimenting
  on humans with a diet in which one eats normally for 25 days and then
  reduce calories to 25% of normal for 5 days.  (It has also been
  hypothesized that eating normally for 55 day and reducing calories
  to 25% for 5 days might be give the same benefit.)
  [BBC News]
  [Valter Longo - Wikipedia]

Note that many of these diets have been considered only from the viewpoint of weight loss and not from the viewpont of any potential anti-cancer effect.

The area where some evidence is available is that human studies have found that fasting before and after chemotherapy seems to heighten the anti-cancer effect and reduces adverse side effets.

Many of the mechanisms underlying fasting are known. The following
survey paper is aimed at fasting and chemotherapy but it also describes,
in general, the various biological mechanisms underlying fasting:

Thursday, January 1, 2015

Blog Updates for December 2014

Jan 1, 2015. In WCRF/AICR Diet and Cancer Report we added: In November of 2014 an update to the original report was published with the following main conclusions. From their web site:
  • "There is strong evidence that being overweight or obese increases the risk of advanced prostate cancer (being overweight or obese is assessed by body mass index (BMI), waist circumference and waist-hip ratio)."
  • "There is strong evidence that developmental factors in the womb, childhood, and adolescence that influence growth are linked to an increased risk of prostate cancer (the taller a man is, the greater his risk of prostate cancer)."
  • "There is strong evidence that consuming beta-carotene (either through food or supplements) is unlikely to have a substantial effect on the risk of prostate cancer."

Monday, December 1, 2014

Blog Updates for November 2014

November 3, 2014.  Added new Twitter category to the Links in the right margin.  New entries: Twitter: [D Martin] [Prostate Urology]

Friday, October 31, 2014

Blog Updates for October 2014

October 31, 2014. In Prostate Cancer Calculators we added: Life Span Rule of Thumb. A rule of thumb is that a person's life span given their current age is the average of their current age and the maximum lifespan of a human. 100 is used as the maximum life span in this calculation even though there are people who live beyond this. The following article shows that his heuristic gives a fairly good approxiation to the life tables for ages 65 yo 95. [decision sciences article]

Wednesday, October 1, 2014

Blog updates for September 2014

Oct 1, 2014. Added Hosp Admin Costs - US and Hosp Admin Costs - Can under benchmarking in the right hand margin of this site.  Key figures are that they are 25.3% of hospital expendistures in the US and 5.92% in Canada.

Monday, September 1, 2014

Blog Updates for August 2014

August 8, 2014 In Prostate Cancer Calculators we added: Risk prior to biopsy. UT Cancer Therapy & Research Center has a prostate cancer risk calculator where the user inputs race, age, PSA, family history of prostate cancer (yes/no/unknown), digital rectal exam (normal/abnormal/unknown), past biopsy (never/positive/negative/unknown) and get back the probability that a biopsy will show high grade cancer, the probability that a biopsy will show low grade cancer and the probability that a biopsy will be negative for cancer and also show it in a graphical form. (The three probabilities will sum to 100% as they are mutually exclusive.) The calculator is discussed in this medscape article.