Hello ...just diagnosed and shocked

Hello, following routine FIT test, had colonoscopy they found 15mm tumour was removed but he wasn't sure had got it all!!!  I had the phone call yesterday confirming biopsy  is cancerous. Ive got to go for CT scan with contrast in 2 days time.  Unfortunately I have Googled lots. The tumour is located mid transverse colon.  Which is right in middle of top horizontal part of colon.  from what Ive read this is rare, 10% and can be difficult to treat.   Ive had polyps removed before and they have been benign.  Last colonoscopy was 2 years ago and there was nothing, was clear so this has grown quickly.  Ive also had quite a few CT scans recently for other investigations and they all came back clear. I was diagnosed with Bladder Cancer 5 years ago.  Non invasive but grade 3, was removed and BCG treatment over 5 years kept me cancer free.  I know that now I have to wait for results of CT scan was told the MDT are likely to review me 10 days afterwards.  Ive just come out of hospital after emergency procedure from complications of the Colonoscopy I had when they removed the polyp.  He put 2 clips in to cauterise but after a week I suddenly started bleeding heavily from rectum. rushed to hospital and it turned out he had nicked an artery. clip must have come out.  It was touch and go had to have blood transfusions and rushed to vascular surgery alternative was removal of whole colon...to stop bleeding!  . Thankfully they fixed the bleeding artery and I came home on Wednesday. Feeling weak anaemic but so relieved that I was home and safe. 2 days later I get the Bowel Cancer diagnosis.  So not really recovered from the hospital trauma etc this has come as a real blow, I almost forgotten that I was waiting result of biopsy. Now Im just not sure when to tell my family they have been through so much worry during past week. I have grown up daughters and 5 grandchildren.  Should I try to wait until I have full diagnosis and treatment option from MDT or do I tell them now?????  We are very close family.  I was due to go to family gathering today at my sisters, just small one for children Halloween...but have pulled out as couldn't face them.