Welcome to the group although I wish that we had met somewhere else. I have included a link click here to the Kidney Cancer UK website which I believe has the best explanation of the staging and grading system used by the medics. The p means that the results are from the laboratory (pathologic) as opposed to c which is determined in a clinical setting. The T1a means that the tumour is less than 4cm in size, this is small for a kidney cancer which are often not detected for some time.
Grade 1 means that the cells look almost normal and are likely to be slow growing.
If a kidney cancer diagnosis was put on a scale this is at the "good" end of the line.
If you have the opportunity it is helpful if you put a few details in your profile as most people will click on that before answering and it can stop you having to repeat yourself many times. If you click on any username where it is highlighted it will take you to their profile to get an idea of what people write in theirs. You can go back and edit it at anytime to add or remove information. It does not need to be as long as mine.
Please feel free to ask any other questions you might have in this forum but you might also find the Macmillan helpline usefull in all sorts of ways.
