The parents of a 23-year-old killed by cancer are not entitled to use their dead son's preserved sperm so they can have a grandchild, an appeals court ruled Tuesday.

The New York state appeals panel issued a unanimous and unprecedented ruling in the case of Mark Speranza, 23, who left semen samples at the Repro Lab Inc. in July 1997 and signed a form directing that they be destroyed if he died. He wanted to be able to father a child if he survived his battle with cancer.

Following their son's death in January 1998, Mary and Antonio Speranza of Edison, N.J., told Repro's operator that they wanted a grandchild and wanted to save the sperm so a surrogate mother could be artificially inseminated.

The lab operator, Awilda Grillo, told the Speranzas their son deposited the specimens for his use only and the specimens had not been screened for donation to a member of the public, as required by state law.

The Speranzas paid Grillo storage fees and asked her to preserve the sperm specimens until a court could decide on custody.

State Supreme Court Justice Jane Solomon ruled that the law barred use of the sperm. She noted that the required screening, specifically a blood test of the donor, was now impossible since Mark Speranza was dead.