Remaining risk after LCIS/Prophylactic mx

I don't think anyone knows with any amount of certainty.  I have LCIS, have not had a BPM, have a weak family history, and I have gotten estimates of my breast cancer anywhere from a high of ~ 85% lifetime risk (from a breast cancer calculator which has NOT been peer reviewed, nor compared to the appropriate populations) http://www.halls.md/breast/risk.htm  to a low of "somewhere between 10 and 60%, but probably closer to 10%" from a 2nd opinion at a NCI-certified breast center.

If you want to have some idea about the state of breast cancer prediction, you may want to read this editorial in a medical journal.  This is about the Gail model, which is the most commonly used breast cancer risk model.  At the NCI website, http://www.cancer.gov/bcrisktool/, it automatically excludes you if you have previously had breast cancer or LCIS.  

The editorial points out that as far as estimating YOUR breast cancer risk (in other words, your personal risk for breast cancer - not the breast cancer risk in your community or area), the Gail model was 'better than the roll of a dice - but not by much.'

Decarli et al. also assessed each model’s performance at the level of the individual woman. A model that discriminates well at this level should consistently predict a higher risk of breast can- cer for women who will be diagnosed with the disease than for women who will not. Decarli et al. randomly selected pairs of women, one of whom was diagnosed with breast cancer and one of whom was not, to determine the frequency with which each model calculated a higher risk for the woman who developed breast cancer. The resulting calculation produced a concordance statistic, whose value could range from 0.50 (equivalent to a coin toss) to 1.0 (perfect discrimination). The concordance statistics for the Italian and Gail models were essentially the same, ap- proximately 0.59 (with 95% confidence intervals that ranged from 0.54 to 0.63). In other words, for 59% of the randomly se- lected pairs of women, the risk estimated for the woman who was diagnosed with breast cancer was higher than the risk estimated for the woman who was not. Unfortunately, for 41% of the pairs of women, the woman with breast cancer received a lower risk estimate than her cancer-free counterpart. Thus, for any given woman, the two models were better at prediction than a coin toss—but not by much. <snip>

Why is it so difficult to develop worthwhile breast cancer pre- diction models for individuals? First, the risk factors used in cur- rent models are widely prevalent throughout the population and are neither highly sensitive nor highly specific. In addition, a risk factor must be very strongly associated with a disease (with a relative risk of about 200) to be worthwhile for screening (18), and the same appears to be the case for accurate prediction using combinations of risk factors. Most risk factors for breast cancer are relatively weak. Even “strong” risk factors, such as older age, mammographically dense breasts, and radiation exposure, are as- sociated with relative risks of less than 10. [Deleterious BRCA1 mutations in young women may be an exception (19).] http://jnci.oxfordjournals.org/cgi/reprint/98/23/1673.pdf  (emphasis mine).

If they have this much difficulty in predicting breast cancer for the 'average' woman without breast cancer, you can imagine how much they know about risk for LCIS women, or to answer your question.

Since relatively few women get LCIS and nothing worse, Specifically, they rose from 0.90/100,000 person-years in 1978-80 to 2.83/100,000 person-years in 1987-89, but then increased only modestly up to 1996-98 where the incidence rate was 3.19/100,000 person-years. However, among women 50-79 years of age, LCIS incidence rates increased continuously over the study's duration. In 1996-98, 50-59 year-olds had the highest incidence rate (11.47/100,000 person-years) and experienced the greatest absolute increase in incidence over the study period (9.48/100,000 person-years). http://www.ncbi.nlm.nih.gov/pubmed/12353815?dopt=abstractplus, I don't think there will be studies with huge numbers of LCIS women soon.

In this study of women with 180 LCIS only and who had excision only, after about 12 years, Table 2 lists the pathologic type, site, and time of recurrences. At the time of the current report, there were 26 patients (14.4%) with IBTRs of all types, including 1 patient with 2 metachronous tumors in the same breast, 3 patients with metachronous IBTR and a CBTR, and 1 patient with a synchronous IBTR and CBTR Nearly 85% of the IBTRs were detected by mammography. Nine of 26 IBTRs (34.6%; 5.0% of the total cohort) were invasive malignancies, and 8 of 9 IBTRs (88.9%) were of the lobular invasive histologic type. The remaining 17 IBTRs included of DCIS alone in 6 patients (3.3% of the total cohort), LCIS only in 10 patients (5.6% of the total cohort), and both forms of carcinoma in situ in 1 patient (0.6% of the total cohort)....Table 4 summarizes the 16 deaths observed in the cohort of 180 patients with LCIS. There were only 2 patients (1.1%) in the entire cohort whose deaths were considered to be related to breast carcinoma. One of those patients had an invasive IBTR, and the other patient had an invasive CBTR. http://www3.interscience.wiley.com/cgi-bin/fulltext/106570353/HTMLSTART

With only 180 LCIS patients, this is a SMALL study.  But with 180 LCIS patients,this is one of the larger LCIS studies I have seen.

Breast cancer risk factors are NOT NOT NOT NOT necessarily additive. For example, it is known that alcohol puts one at higher risk for breast cancer.  However, the addition of other risk factors in addition to alcohol use does NOT necessarily increase one's breast cancer risk. http://www.ncbi.nlm.nih.gov/pubmed/19960437.  That's why Dr. Hall (in his breast cancer risk model, stated above, pointed out his breast cancer risk model has NOT been compared to populations.) Since the population of women with LCIS and nothing worse is small, I think I will be waiting for quite some time to find an appropriate study. They have a hard time knowing the risks because (as far as I know) there aren't studies to compare the two groups.

In selected situations, bilateral prophylactic mastectomy with or without reconstruction may be considered when atypical hyperplasia or LCIS is diagnosed. Although this reduces risk for developing subsequent breast carcinoma by 90%, patients selected for prophylactic mastectomy represent a small subgroup of lobular neoplasia patients and generally have other risk factors, such as strong family history or evidence of genetic predisposition. http://www.ncbi.nlm.nih.gov/pubmed/16687097 I don't know if this is a review article. (I suspect it is.)It may provide a reference for the 90%figure.

So there is real uncertainty about what your risks really are.

Yes, thank you for pointing that out Minnesota!

These studies are probably intended to only include classic LCIS, since that was mostly what was known.  In order to get studies that have enough  LCIS subjects (like more than 30 or 100???), they may have to combine the LCIS women at several different institutions.  In that case, there is the additional fly in the ointment that some of the LCIS women were diagnosed by different pathologists, or may use different diagnostic criteria.   There is the on-going problem too that LCIS could be mis-diagnosed, or that other entities (such as PLCIS, DCIS, or invasive) could be present but not detected in these LCIS women, since LCIS is normally found as an incidental finding on biopsy.  It is certainly possible that some of these 'LCIS' patients could really 'only' have ALH and/or ADH.

According to this article, pleomorphic LCIS was first described in 1998, http://cme.medscape.com/viewarticle/560671_8, so of course there can't be any studies of pleomorphic LCIS women starting before this time.  Of course, some of the LCIS women who were included in LCIS studies before then may have actually had PLCIS.  Additionally, of course, since pleomorphic LCIS is a rare entity in the world of LCIS, there are even fewer PLCIS women on which to do studies than LCIS women.

Thank you again, Minnesota!

We don't know if the risks are cumulative.  If someone has 2 risk factors for something (theoretically), the risk factors may be additive, produce no additional risk, or even be subtractive.  

  I have seen opinions that in the people who had LCIS diagnosed after age 50, that family history did NOT predict who got subsequent bc.  I don't know if that is a widely held position.  But, in any event, for any group of people, they need to look at the specific population involved - i.e. the people with the two (or more) specific risk factors - to see if the model fits.  Since the group of classic LCIS patients is small, its going to be hard to find the subjects, let alone the research funding/expertise.

Leaf - You seem to know and understand a lot about LCIS. I was mainly told because of also having DCIS that they treat it and the LCIS will be taken care of in the process. I had double mastectomies. But NO followup at all. I was told I'm done. From what I have read from you that follow up should be more standard procedure, Yes? If so who is best to talk with as the oncologist pretty much blew me off. Thanks.

Hi Stanzie -   Of course, if you develop a new lump or lesion in your chest area or lymph node area, you should get it checked out. 

No, I'm not saying you should have followup.  I don't know - I haven't examined the issue.

   I know VERY LITTLE about DCIS (as I don't have it) or prophylactic mastectomy followup, and the risk of breast cancer after bilateral prophylactic mastectomy.   I've seen quotes from 2% to about 10%.

Ha - they misspelled Dr. Hartman's name.  It is really Lynn C. Hartmann. But I still can't find the abstract in Pubmed.  Maybe it was published in a book.  Pubmed doesn't review those.

This study (which Dr. Hartmann co-authored) opined the Gail model underestimated atypical hyperplasia risk. http://www.ncbi.nlm.nih.gov/pubmed/18854574