When you think of ShopRite, you think kale, ice cream and maybe a really excellent bakery section. You probably don’t think much about cancer diagnoses. But on a recent Saturday at Brown’s ShopRite in East Falls, dozens of women lined up for a potentially lifesaving measure they might not otherwise be able to afford: A free mammogram.

The Jeff Brown-owned ShopRites, largely located in lower-income areas, are something of de facto community centers, offering, in some cases, on-campus credit unions and health clinics. The screenings, provided by Fox Chase Cancer Center, were part of the supermarket chain’s annual cancer awareness day, something Sandy Brown, director of Brown’s Superstores, says is part and parcel of their mission. “The communities that are least likely to get early detection are urban communities, similar to where our stores are,” she says.

ShopRite spread the word through several local churches, including Enon Tabernacle Church in North Philadelphia and Mt. Airy Church of God and Christ. Fox Chase provided the mobile mammography van, a version of which the medical center has had on the road since 1988. On a good day, Fox Chase will screen 10 to 20 women at a location. At the ShopRite that day, 36 women got free mammograms.

Nowadays, we know, as with all cancers, that the earlier a woman detects her breast cancer, the easier it is to treat. But mammograms do not necessarily come cheap.

“We opened up our community room, we had food, we had dietitians there who could talk to them about healthy eating,” says Brown. “And the nicest thing is that as they were waiting, they were all interacting with each other about the importance of having early detection. It was really all the way around a great experience for everyone who went through it.”

Breast cancer is among the most common and insidious forms of cancer — and among the most easy to detect. The lesions and lumps that lead to breast cancer are obvious; they’re not somewhere deep inside, metastasizing unbeknownst to the sufferer. Since the dawn of modern medicine, doctors have tried to treat breast cancer with invasive treatments, from full-bore proto-mastectomies to attempting to burn out the cancer with white-hot prods to, worst of all, essentially melting it off with acid.

Nowadays, we know, as with all cancers, that the earlier a woman detects her breast cancer, the easier it is to treat. But mammograms do not necessarily come cheap. The going rate for a mammogram without insurance, according to Linda Hammell, director of community screening for Fox Chase, is around $700, which is a lot of money for what amounts to a digital snapshot of fatty tissue. This leads many uninsured, at-risk women to avoid going for screenings, just like many uninsured men avoid prostate exams.

For many more, it’s the simple reality of timing: Hospital mammograms often have months-long wait times for appointments, which makes it difficult to schedule, particularly for women whose work hours are hard to predict. But avoiding the screening has its own financial (not to mention health) risk: According to one study from 2010, $7.8 billion was spent on breast cancer treatment alone — that’s out of the roughly $160 billion that was spent on treating the emperor of maladies that year.

According to the Pennsylvania Department of Health, an estimated 27 new cases of breast cancer were found in state every day, and roughly nine women died of breast cancer daily. What’s more: While breast cancer incidence roughly matches the national average in Philadelphia, the border counties‚ Bucks, Montgomery, Chester and Delaware — have incidence rates much higher than normal. Breast cancer is far and away the most common cancer in Pennsylvania, with an incidence rate of roughly 300 cases per 100,000 people in state.

“The idea was that more women needed this, and so we grew that into a true community-based screening, where we’re not just screening women on a corporate level or have insurance, but women who are underserved and find it a little difficult and uncomfortable at times to get a physical mammogram.”

An estimated 20 percent of women who get mammograms are called back for further examination, and around 10 percent of those who get called back receive a biopsy. In total, out of 1,000 women who receive mammograms, five will ultimately test positive for breast cancer, according to The American College of Radiology. Fox Chase’s mobile unit yields similar results.

The idea for the mobile mammogram unit didn’t come from Fox Chase initially. It came from Aetna, the insurance company which, in the 80’s, would send a mobile mammogram unit out to its corporate partners. It benched the program in 1988, the year Fox Chase unveiled their own roving mammogram machine. It is still the only mobile mammogram unit in Philadelphia, and one of two in the state, according to Hammell. (Some states, she says, have almost no mobile units available, while others, like Texas, have five.)

“Some [corporate] partners we’ve had almost 30 years,” Hammell says. “Then we got the idea of not just bringing our mobile screening to the convenience of employers and employees who need to leave their desk for 10 minutes to get their mammogram. The idea was that more women needed this, and so we grew that into a true community-based screening, where we’re not just screening women on a corporate level or have insurance, but women who are underserved and find it a little difficult and uncomfortable at times to get a physical mammogram.”

To get a screening from Fox Chase’s mobile mammogram machine, women must receive a prescription from their doctor. Those who have insurance can get the screening through their providers, and women who don’t can check if they qualify for a Komen Grant, which makes the mammogram free of charge, on site. If a woman is called back for more work after her test, she’s free to go to any medical group she wants, so long as her doctor clears it.

The Fox Chase unit operates within a 25-mile radius of Philadelphia. It has conducted tens of thousands of tests since its inception, and regularly conducts more than 3,000 mammograms per year. It is on the road 175 days out of the year, and is heavily in demand, especially on weekends; Sandy Brown says she had to wait months for an opening. That is precisely the point: Bringing mammograms to women when, and where is most accessible.

“These are women that know in their heart that they should be getting mammograms because that’s what their doctor recommends,” Hammell says. “These are women who don’t take time for themselves — that’s why they have to do it at work. These are women that, because of the language barrier, know that we have an interpreter on the unit to help complete forms and understand the procedure for the mammogram. These are women who are afraid to go to a big medical facility, and prefer the model of a mobile unit coming to them in their neighborhood.”