(BPT) - From national sports events to local fundraisers, breast cancer seems to be discussed everywhere. But despite all the conversations around breast cancer, most Americans are not talking about, and have never even heard of, a type of breast cancer that is on the rise.

Accounting for up to 15% of all breast cancer diagnoses, lobular breast cancer is the second most common type of breast cancer, around 50,000 cases a year in the U.S. - but its prevalence has not guaranteed its visibility. Awareness of lobular breast cancer remains disproportionately low among American adults, 4 out of 5 of which have never heard of the disease. And despite having an annual incidence that averages higher for women than brain, kidney, liver, pancreatic or ovarian cancer, a lobular breast cancer diagnosis is foreign to nearly 50% of people personally diagnosed with breast cancer.

This Breast Cancer Awareness Month, it is important to make yourself aware of all types of breast cancer, including lobular breast cancer.

Four key things to know about lobular breast cancer:

• The tumors don't usually form as lumps: Lobular breast cancer, also known as invasive lobular carcinoma (ILC), can have symptoms other than a lump. The cancer cells grow in single-file lines or sheets through the breast tissue rather than forming a distinct, dense lump.
• Detection can be more challenging: Because of the way it presents itself ILC can be less conspicuous on mammography and harder to detect by self-exam. This often means that many patients find their lobular breast cancer undetectable until a biopsy confirms the diagnosis.
• Metastatic lobular breast cancer is hard to monitor and treat: Because lobular breast cancer is hard to image, it makes monitoring metastatic lesions and whether they respond to treatment nearly impossible. It is hard to know when to switch a metastatic lobular breast cancer patient to a new line of treatment to stop tumor growth and sadly, for this same reason, metastatic lobular breast cancer patients are often excluded from clinical trials of new drugs.
• ILC incidences are increasing three times faster across all demographics than any other breast cancer type.

"Unfortunately, despite how relatively common lobular breast cancer is, it has historically been overlooked by research and has no specific treatments," says Dr. Rebecca Shatsky, Professor of Clinical Medicine, UC San Diego Health, Breast medical oncology team leader at Moores Cancer Center and Chair, Lobular Breast Cancer Alliance Scientific Advisory Board.

But, as Lobular Breast Cancer Alliance Executive Director and 8-year ILC survivor Laurie Hutcheson says, "Lobular breast cancer is not rare, has troubling and unique characteristics that are quite different from the more common breast cancer types and urgently needs attention. There are more and more women diagnosed with ILC every day wondering why even now so little is known about lobular breast cancer and when this will change. More attention and research into ILC is critical to changing this narrative and the lives of lobular breast cancer patients everywhere."

To learn more about lobular breast cancer, the only lobular-breast-cancer-focused patient advocacy organization in the country, visit Lobular Breast Cancer Alliance.