As sleety rain kept falling, the activists anguished about whether to go ahead with plans to lie on the ground on a recent Saturday evening.
Their "die-in" was intended to symbolize the fact that, despite all the progress in taming breast cancer, it still takes about 40,000 lives a year in the United States. Imagine wiping out the population of Wilkes-Barre or Atlantic City. Every year. For three decades.
Still, the demonstrators had to be pragmatic. Most members of their new group, MET-UP, had metastatic breast cancer and had to be careful to protect their fragile health.
The die-in was out.
But after their candlelight procession reached Independence Hall, some members took charge. Two women with early-stage cancer got down on the frigid pavement. Carl "Mac" Holmes - proof that men are not immune to advanced breast cancer - watched his wife, Robin, join them.
Ultimately, about half the 70 women and men lay side by side, holding "Dying for the Cure" placards. The rest sang, hugged, or spoke of those who had died.
For many, the sadness masked seething.
"The breast cancer movement has been pinkified and feminized. We've been told to play nice," said Jennie Grimes, 35, of Los Angeles. "I don't think there has been the kind of anger that demands change."
MET-UP is part of a bold new wave of activism by patients whose breast cancer has spread, or metastasized, to distant organs, reducing their life expectancy to a median of three years. Last year, Grimes and Beth Caldwell, 39, of Seattle, founded MET-UP - inspired by the AIDS group ACT-UP - after attending an advocacy training program for metastatic patients offered by Living Beyond Breast Cancer, the 25-year-old Bala Cynwyd-based organization.
At the forefront of this movement is the Metastatic Breast Cancer Alliance, an unprecedented union of metastatic patient groups, traditional breast cancer nonprofits, research foundations, and drug companies including Novartis, Eli Lilly, and Celgene.
In an exhaustive 2014 report, the alliance decried "a lack of awareness about metastatic breast cancer and how it differs from early-stage breast cancer; little research funding to combat this unique and deadly disease; and a lack of accurate statistics on the incidence, prevalence, and survival."
Millions of cells may be shed by the original tumor into the bloodstream every day. Yet only rare, aggressive mutants survive in transit, then escape from a blood vessel, colonize a different organ, and generate a new malignancy, sometimes after years of dormancy.
"To achieve metastasis, cancer cells must evade or co-opt multiple rules and barriers that were refined over hundreds of millions of years of evolution," Memorial Sloan-Kettering metastasis researcher Joan Massague wrote.
Deepening this mystery, premenopausal women and African American women of all ages are more likely than other women to develop fast-growing, aggressive breast cancers, the kind that spread.
The number of patients who develop metastasis is unknown, not just for breast cancer but all types. That's because the federal cancer surveillance program collects data on the stage at initial diagnosis, but not on recurrences or progression.
About 5 percent of initial breast cancer diagnoses are Stage IV, or metastatic, the data show. But the percentage of early-stage patients who later develop metastatic disease - 20 percent to 30 percent - is an estimate.
An estimated 150,000 to 250,000 people in the U.S. are now living - scan to scan, and therapy to therapy - with terminal breast cancer.
Federal data also feed a misconception about long-term survival that rankles patients such as Grimes. A vegetarian marathon runner, she felt a breast lump eight years ago - at age 27 - that led to a diagnosis of Stage II breast cancer. The data show that 93 percent of Stage II patients live at least five years. In the public mind, the five-year milestone - which Grimes hit in 2012 - is synonymous with "cured."
While newer targeted therapies have extended survival for metastatic patients - by months, not years - neither Grimes nor Caldwell responded to the latest one, Ibrance, a first-of-its-kind targeted therapy approved last year. Nor did they test positive for genetic defects known to increase breast cancer risk.
Caldwell, who has two young children, already had cancer in her bones by the time she felt a breast lump two years ago at age 37.
Therein lies a misconception about "prevention." Screening mammograms are not recommended until age 40, and the X-rays can miss tumors. Yet surveys show that because of the emphasis on early detection, many people believe women who develop metastases did not take adequate preventive measures.
Caldwell's cancer was found in her brain a year ago. That spot responded to radiation and chemotherapy, but now she may need a different chemo drug because her most recent scan showed cancer in her liver.
Before illness forced them to go on workers' disability insurance, Caldwell was a civil rights lawyer and Grimes, a sociologist, worked for an HIV/AIDS support organization. She even helped stage an AIDS "die-in" at the White House in 2005.
"The needle hasn't moved," Grimes said. "Forty thousand a year die of metastatic breast cancer. It's the same number as at the height of the AIDS epidemic."
The activists frequently say metastatic breast cancer research is underfunded.
"I know science takes time. And I don't know that breakthroughs will come in time to save my life," Caldwell said. "But if we always treat metastatic patients as terminal, it's not going to change. Of $15 billion spent on breast cancer research, only 7 percent went to study metastatic disease."
Those numbers come from the Metastatic Breast Cancer Alliance's analysis of more than a decade of clinical trials in the U.S. and Britain.
Researchers say more funding would help, but it would not necessarily level technological and professional obstacles.
At Sloan-Kettering, for example, Massague and his lab spent five years and several million dollars just on a crucial preliminary step: genetically engineering a mouse that could be used to study how metastatic cancer arises and progresses.
They recently published results from arduous experiments using the mice to identify a key piece in the complex puzzle of how malignant cells hide out for years, undetectable, then multiply explosively.
Even more than other basic research fields, Massague said, metastasis is a risky career move for young scientists.
"It take guts for them to say, 'Yeah, let's do that,' " he said. "If they fail, they'll be forgotten."
Another complex dynamic involves metastatic activists' place within the larger world of breast cancer advocacy.
"Women with metastatic cancer continue to express feelings of isolation as their stories and struggles do not align with the public image and understanding of breast cancer," says a recent report by Pfizer and breast cancer leaders.
And if the women feel isolated, men with metastatic disease feel invisible.
That's why Holmes, a retired Air Force commander and former FedEx pilot who lives in Collierville, Tenn., joined MET-UP after his wife discovered the group on Facebook.
"I've been in a man's world my whole life," Holmes said. "When I first was diagnosed, I was embarrassed to say I had breast cancer. Now, I'll help in any way I can. I can speak and I'm not afraid to."
This is not the first wave of activism by metastatic patients that the breast cancer world has seen.
Jean Sachs, CEO of Living Beyond Breast Cancer, recalls desperate women chaining themselves to the gates of Genentech in 1994 to demand access to Herceptin, the breakthrough drug then in clinical testing.
What has changed, Sachs and others agree, is that social media have enabled far-flung metastatic patients to organize and mobilize. And venerable breast cancer nonprofits have recognized the need for programs dedicated to these patients.
Living Beyond, for example, commissioned a "Silent Voices" survey a decade ago. That led to annual conferences for metastatic patients and, beginning last year, the advocacy training program.
Trainees have joined research review committees, launched blogs, testified before policymakers - and staged die-ins.
"Some people talk about cancer being a gift. I really disagree. It's not a gift," Caldwell said. "But living this life, it's important to find meaning. As someone who lost my career, this is a way I can find meaning out of this experience."