Source: Circulation  |  Posted 5 years ago

By Alison Palkhivala

MONTREAL, CANADA -- September 21, 2006 -- A prognostic index developed from 4 molecular markers can, when used together, help determine which patients with serous papillary ovarian carcinoma will respond best and worst to chemotherapy. On their own, each of these markers is only of weak prognostic value.

To date, the prognosis for serous papillary ovarian carcinoma has been unpredictable. "We know that some cases have a complete response and then a long period of progression-free survival and other cases even progress during chemotherapy," said lead investigator Ion Popa, MD, medical resident, department of pathology, Laval University, Quebec City, Canada.

In a previous study, Dr. Popa and colleagues compared gene expression in tumours that responded to therapy and tumours that did not. They found a weak correlation between prognosis and expression of 4 antibodies: MMPI, HSP10, p53, and Ki67. They subsequently hypothesized that, used together, these 4 markers might perform as a strong marker of prognosis.

Dr. Popa presented the results here yesterday in a poster at the 26[^]th[] International Congress of the International Academy of Pathology (IAP) in a poster presentation on September 19[^]th[].

The researchers compared gene expression of chemoresistant and chemosensitive serous papillary ovarian carcinoma tumours using frozen tumour tissue samples from 166 women with advanced disease. Most had undergone treatment with taxol and a platinum compound. They performed immunohistochemical analysis on the samples to determine the expression of MMPI, HSP10, p53, and Ki6.

Good prognosis was associated with positive staining for HSP10, p53, and Ki6 (high intensity) but negative for MMPI. Poor prognosis was associated with negative staining for HSP10, p53, and Ki6 but positive for MMPI.

The investigators then developed a prognostic index in which patients received 1 point for every HSP10, p53, and Ki6 (high intensity) stain that was positive and -1 point for every MMPI stain that was positive.

Overall, 2% of patients had a prognostic index of 0; 18% had an index of 1; 35% an index of 2; 34% and index of 3; and 11% an index of 4.

"We compared groups with a low prognostic index [2 or less] with those who had a high prognostic index [3 or more], and the log rank test showed that there was a difference between the groups," Dr. Popa said. The 2 groups had different Kaplan-Meyer curves for progression-free survival ([]P[] = .0012)

According to Dr. Popa, this index can help clinicians determine in advance which patients are most and least likely to respond to chemotherapy, which can be used to tailor treatment.

[Presentation title: "A Prognostic Index of Advanced Ovarian Carcinoma Based on 4 Markers. Poster 465]