🚀 go-pugleaf

Hi everybody,

Last week when I presented I was asked some questions which I answered. I
answered to the best of my knowledge and what I had found in my
researching, which consisted of reading many articles and books.

Because retinoblastoma is a very rare childhood cancer of the eye, all
articles made references to infants and never adults.  I have recently
found new material that I thought that I would share with you and clarify
and misconceptions.

This is what I have found:
A unilateral retinoblastoma (Rb) has been reported to be found in a 26
year old woman (recent article).  " This tumor usually affects young
children; the mean age at the time of diagnosis usually ranges from 10-25
months. Rb occurring in adults is a very rare finding.  In most large
series of Rb's no adults are included.  The late onset of ocular symtoms
(26 years of age) is unusual."  Ophthalmology vol 104, (1):1997.

Also, " Rb has been newly diagnosed in children between the ages of 7 and
18 and has been found to occur even in adults of ages 24, 26, 45, 48, and
60 years.  The reason for the development of this tumor at such a
developed age is speculative.  Some authors believe that the tumor may
arise from a reactivated previously undiagnosed spontaneously
regressed/arrested Rb.  Others have proposed that the persistence of an
embryonal retinal cell may contribute to the unusual development of the
tumor at such an advanced age." Ophthalmology vol 98, (3):1991.

The retinal cell susceptibility to malignant transformation must be
present only at a specific developmental stage.  The very earliest retinal
cells are probably resistance, since infants are only rarely born with
advanced ocular tumors.  Fully differentiated nonproliferating retinal
cells are also resistant and only rarely does >RB arise in adults."
Retinoblastoma, edited by Frederick C. Blodi.

There was no other info about mutagens except that radiation therapy can
cause tumor formation. And one web site, non-medical, by a Rb patient,
stated, "....There are environmental factors all around that could cause
these mutations."  http://www.acadia.com.net/mikear/adult.html

I hope that I was able to tell you a little bit more info on RB.

s_harve@alcor.concordia.ca
Shona Harvey
Have a nice day!