Tumor Vaccine Causes Regression, Reduces Metastasis In Incurable Melanoma.(Brief Article)

2001 NOV 7 - (NewsRx.com & NewsRx.net) -- by Sonia Nichols, senior medical writer - Using a new vaccine consisting of autologous tumor cells complexed with a hapten, investigators at Thomas Jefferson University's Kimmel Cancer Center have seen marked regression of metastatic tumors in patients with surgically incurable metastatic melanoma.

In previous studies, vaccines containing autologous tumor cells that had been amended with dinitrofluorobenzene (DNP) were effective for producing cell-mediated immune responses leading to inflammatory activity at areas of metastases, according to David Berd and colleagues.

"In this study we determined whether DNP vaccine could induce regression of established metastases," commented study authors David Berd and colleagues.

Over 90 patients with incurable metastatic melanoma participated in the study, which evaluated delayed-type hypersensitivity (DTH) to melanoma antigen before and after vaccination, assessed tumor regression following immunization, and analyzed survival outcomes. Each patient received low-dose regimens of cyclophosphamide prior to vaccination.

Of the 83 patients able to be evaluated, "There were 11 antitumor responses: two complete, four partial and five mixed," Berd and coworkers said. "Both complete responses and two of the four partial responses occurred in patients with lung metastases."

Partial responses were observed from as short as 5 months after treatment to as long as 47 months or later, while the two complete responses occurred at 12 and 29 months post-therapy.

"Tumor regression required at least four months to become evident and in two cases maximum regression was not observed until one year after beginning treatment," ...