On the Friday before prom, when most girls are finalizing their hair appointments and picking out last-minute jewelry, Copiague’s Siearah Rodriguez checked into Brookhaven Memorial Hospital Medical Center to undergo her third operation following a breast cancer diagnosis.

On April 25, 2015, near the end of her junior year at Walter G. O’Connell Copiague High School, Rodriguez discovered a Phyllodes tumor on her right breast. She immediately went to the hospital with her mother, and the exam found that this typically benign tumor contained ductal carcinoma in situ (DCIS), or cancerous cells within the milk duct.

“They had never seen that together,” Rodriguez said, adding that the mutation in Rodriguez’s tumor is so rare that very little research had existed.

“I was the youngest person there getting a mammogram and biopsies,” Rodriguez said. “It was tough. There was [support] groups of 40-year-old women, and I can’t relate to them.”

A week after the discovery, she underwent surgery to remove the lump. Since then she has received two other surgeries and multiple follow-up treatments and examinations at Memorial Sloan Kettering Cancer Center in Manhattan and oncology centers throughout Long Island With her cancer in remission since August 2015, Rodriguez will stay closely monitored as she enters Suffolk Community College with plans to study forensic psychology.

The time spent traveling and waiting in doctors’ offices caused her to miss class time, but Rodriguez said she’s found support from her high school community.

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“They’re really good to me here [at Copiague High School],” Rodriguez said. “When I came back to school, I had to make up work, but the stress level wasn’t really there because my teachers always worked with me.”

The senior prom, held Thursday night at Floral Terrace in Floral Park, was more than just a celebration of the culmination of high school for Rodriguez. She was celebrating her fellow students and teachers who helped her throughout this challenging year.

Fundraisers organized by senior advisers and Spanish teachers Flora Hernandez and Danielle Poletti raised money to go toward Rodriguez’s GoFundMe page, which helped supplement medical bills and transportation costs for treatments.

“Just to see the whole class and all the students be so supportive and so sensitive to her situation, it brought unity,” Hernandez said.