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CancerTherapyAdvisor.com

Metastasis-directed therapy alone may delay initiation of systemic therapy in select men with a solitary metastasis after hormone-sensitive prostate cancer recurrence, according to a study published in The Journal of Urology.

Among 124 patients with solitary oligorecurrent metastases observed on C-11 choline PET, 67 underwent surgical excision and 57 received stereotactic body radiation therapy (SBRT) as metastasis-directed therapy (MDT), without concurrent androgen deprivation therapy (ADT) or systemic therapy. Surgery was mostly recommended for lymph node metastasis. Radiation therapy was mostly recommended for bone metastasis.

A prostate-specific antigen decline of more than 50% occurred in 80.5% of the surgery group and 40.3% of the SBRT group. The 3-year radiographic progression-free survival rate was 29% in the surgery group and 16.5% in the SBRT group.

In a subset of patients, surgery was associated with a median 14.9-month delay in radiographic progression and a median 18.5-month delay in initiation of systemic therapy. SBRT was associated with a median 12-month delay in radiographic progression and a median 17.8-month delay in initiation of systematic therapy.

“This study represents the first reported series of MDT without ADT in patients with solitary metastatic prostate cancer,” the researchers wrote. “These results suggest that MDT without ADT can delay systemic therapy and likely has a role in the treatment algorithm for oligometastatic prostate cancer.”

The researchers noted that neither the American Urological Association nor the National Comprehensive Cancer Network (NCCN) recommends MDT as part of guideline-based care. However, the NCCN “has recently allowed for consideration of MDT to improve progression-free survival.”

The researchers added that their report suggests the need for “a revision of the guidelines to allow for MDT in carefully selected patients.”