In February 2024, while being treated for pneumonia, doctors noticed that Rebecca Santorelli’s spleen was enlarged.
“No one was concerned at first,” recalls Santorelli, 61, who lives outside of Albany, New York.
Doctors estimate spleen size with fingerbreadths — or approximate widths of a finger — below the rib cage, with normal being about zero. At first, Santorelli’s spleen measured three fingers. As months passed, it grew to more than five and then to 16 centimeters below the rib cage. Santorelli’s blood counts were also low, though for her, that was unsurprising. Santorelli takes an immunosuppressive drug to treat an autoimmune disorder. Eventually, her medical team referred her to a local hematology/oncology specialist.
“I wasn’t alarmed until he said, ‘I think you have MDS,’” says Santorelli.
Myelodysplastic syndrome (MDS) is a type of blood cancer that can progress to acute myeloid leukemia (AML). Santorelli and her husband, Bob, were familiar with AML as her father had died from the disease 39 years earlier.
A second opinion
The oncologist who suspected Santorelli had MDS urged her to get a second opinion.
“He asked, ‘Do you want to go to New York, or do you want to go to Boston?’” Santorelli recalls. “I didn’t miss a beat. I wanted to go to Dana-Farber.”
She visited Dana-Farber’s Center for Early Detection and Interception of Blood Cancers in May 2025. The Center is the first-of-its-kind clinic to specialize in evaluating patients with abnormal blood counts to determine if they have a precursor condition that raises their risk of developing a blood cancer.
Virginia O. Volpe, MD, confirmed that Santorelli’s blood stem cells carried a gene mutation related to leukemia. However, that finding, along with her bone marrow findings, did not clearly indicate MDS or AML. Instead, she appeared to have clonal hematopoiesis of indeterminate potential (CHIP) or CCUS (clonal cytopenia of undetermined significance) — precursor states that can increase the risk of MDS or AML, though the degree of risk varies by individual.
Santorelli’s combination of abnormal blood work and enlarged spleen raised significant concern for Volpe.
“Becky’s data wasn’t fitting together into a clear diagnosis,” she recalls. “We just kept digging.”
Volpe initiated a series of laboratory tests, including a test to look for tick-borne diseases. In July 2025, Volpe called with news: Santorelli had babesiosis, a rare illness caused by a parasite spread by ticks in immunocompromised patients, such as Santorelli, the disorder can progress to a chronic, potentially life-threatening illness, frequently presenting with abnormal blood work and an enlarged spleen.
Santorelli was astonished. She didn’t have cancer, and she couldn’t wait to tell her husband.
“I just had to tell him in person,” she says. “I’m going to be okay.”
Return to health
After a six-week course of antibiotics, Santorelli’s spleen returned to its normal size. By September 2025, her blood counts were within the normal ranges, and the abnormality in her bone marrow had resolved.
“It feels like a cloud has been lifted,” says Santorelli. “I feel better than I have in a very long time.”
Going forward, Santorelli can no longer use the immunosuppressive medication previously prescribed for her autoimmune disorder. She is optimistic that, with Volpe’s guidance in consultation with her rheumatologist, her care team will identify alternative treatments to manage the condition. Santorelli will also continue annual follow-ups with Volpe to monitor her CHIP. Based on Volpe’s assessment, her risk of progressing to MDS or AML is very low — approximately 1% over the next 5–10 years.
“I’m so grateful to my original oncologist for encouraging the second opinion,” says Santorelli. “Dr. Volpe left no stone unturned to make sure that her diagnosis was accurate and that I wasn’t treated for something that I didn’t have.”