DCIS & PALB2 & CDH1 positive

ColdInOntario - have you had an opportunity to sit down and delve carefully into this situation with a qualified genetic counselor? If not, that would be item number one on my to do list. Be pushy and persistent if you need in order to get this scheduled soon so that you don't need to hold up your treatment too long. I'd also have a long discussion with your medical oncologist (again, sooner rather than later) and, if possible, get a 2nd opinion at a highly ranked cancer center. With 2 mutations (and make sure they're not Variants of Unknown Significance but actual deleterious mutations) you really need expert insight.

You're in a real grey area - given your age and the fact that it's DCIS rather than invasive. I didn't know about my mutation until after I was diagnosed (I was the same age as you) and I really wish I'd known about it before hand so that I could have perhaps taken steps such as a mastectomy or prophylactic tamoxifen. At the same time, even with that knowledge opting for bilateral mastectomy would have been a vert tough decision. In your case, given that you already have DCIS it gives you a chance to look ahead and see how you would be most comfortable addressing this situation and it gives you maybe a bit more information to work with.

FORCE (mentioned above) is a great place to start. Here's a link to another site that may be helpful: https://www.nostomachforcancer.org/about/hereditary-diffuse-gastric-cancer/lobular-breast-cancer

At this point, I'd say get on the phone and start working on those consults - they're probably the most important step right now! Good luck with it all. It's a lot to take in and figure out in a relatively short period of time, isn't it?

Amelia, I just read a little on CDH1, it is associated with a high risk of ILC. I never had genetic testing because of no family history. I don't think my insurance woud cover the cost. I might have that gene too. I had both idc and ilc gastric surgery sounds horrid. I am interested in what your oncologist has to say.

I think I am going to have a glass of wine. I can't believe anyone would suggest removing the stomach as a precaution. I would need more evidence I was definitely going to get stomach cancer before I did that. Hope you get through your chemo without too much grief. It has been 7 years NED for me. Lily55 has a very similar diagnosis as yours and she is doing pretty good.

I'm not sure whether expressing horror and disbelief is going to help Amelia feel any better right now. A simple internet search provides the reason this surgery is under discussion. From Genetics Home Reference: https://ghr.nlm.nih.gov/gene/CDH1

"More than 120 inherited mutations in the CDH1 gene have been found to cause a familial cancer disorder called hereditary diffuse gastric cancer (HDGC). People with CDH1 gene mutations associated with HDGC have a 56 to 70 percent chance of developing stomach (gastric) cancer in their lifetimes. Women with these mutations also have a 40 to 50 percent chance of developing lobular breast cancer....In addition, a specific inherited variation in the CDH1 gene is thought to increase the risk of prostate cancer." (emphasis mine) Another source explained that the 70% is for men and the 56% is for women. http://www.cancernetwork.com/gastrointestinal-canc...

Keep in mind that there is a difference between a somatic mutation and a germline mutation. A somatic CDH1 mutation is the hallmark of ILC; it will show up in the breast tumor biopsy when tested. So all of us with ILC would have this mutation show up in the tumor. A somatic mutation is present only in the cancer cells, not in every cell of the person's body. It is not inherited and does not confer the familial gastric cancer risk. A germline CDH1 mutation, on the other hand, is present in all the cells of the body and can be passed down to future generations. Most people with ILC do not have a germline CDH1 mutation, which is rare, but a germline mutation is what Amelia is facing.

Amelia, I am sorry you have been dealt this hand. I hope the genetics counselor is an expert in CDH1 or can refer you to one. The right counselor should be able to help you understand your own personal risk, and help you weigh the risks and benefits of surgery. They will look at your family history and the particular CDH1 mutation you have. With such a diagnosis I would want to get two expert opinions, and be cared for at a major cancer center.

The resource Hopeful mentions above appears to have good information and support. No Stomach for Cancer:

https://www.nostomachforcancer.org/about/hereditar...

Meow, I hate to see you worried about something so rare. There are so many causes of stomach aches, you know, and you could ask your PCP to help figure it out. As you will see from the criteria below, if your family history does not show diffuse gastric cancer, or two or more ILC cases under age 50, they don't suspect a germline CDH1 mutation. But if you are still worried, you could ask to test for it, or seek a cancer gene panel like Amelia did. Ambry has a good one. For what it's worth, I was under 50 and premenopausal when diagnosed with ILC. Eventually I had a panel done (blood test) for another reason, and it showed no CDH1 mutation.

From the nostomachforcancer site:

Hereditary Diffuse Gastric Cancer testing criteria have been established and are considered in families who meet any of the following criteria:

• Two or more cases of gastric cancer in first- or second-degree relatives, with at least one case confirmed to be diffuse gastric cancer
• One instance of diffuse gastric cancer diagnosed under age 40
• A personal or family history of both diffuse gastric cancer and lobular breast cancer, with one diagnosis under age 50

Also, families in whom testing could be considered are those who meet any of the following criteria.

• Bilateral lobular breast cancer or family history of two or more cases of lobular breast cancer under age 50
• A personal or family history of cleft lip/palate in a patient with diffuse gastric cancer
• In situ signet ring cells and pagetoid spread of signet ring cells

Affected patients from families meeting the criteria are referred for genetic counseling and testing for a CDH1 gene mutation. The genetic testing is performed in two stages, diagnostic testing, and predictive testing. Diagnostic testing is done using a blood sample from a patient affected with gastric cancer, to identify if a mutation in the CDH1 gene exists to cause cancer. If a mutation is identified, healthy family members who are at risk for inheriting the same mutation may choose to undergo predictive testing for the same mutation.

Meow - I’m in a state of panic with a positive piece of paper in hand. Please don’t over worry yourself without knowing. Get your test done for piece of mind. I had a 40+ gene panel done.

It doesn’t matter if your tumor is available or not as that is a somatic test not a germ line test. All ILC tumors will be positive for loss of L-Cadherin. That is the hallmark of ILC.

ShetlandPony- thank you from the heart for posting all that you have. Of course I’ve read everything on the internet but it is becoming a blur - partially from the tears.

We have no known history of GC which is good and I’ve had various endoscopies over the years for my iffy tummy so maybe I will be spared. I am, however, seriously believing the gastrectomy will be my plan for piece of mind.

I’m 48 and aside from the whole ILC shitstorm was extremely healthy. Maybe the right time for surgery and then get onwith life.