[Comparison of Response to Chemotherapy between Ovarian and Extraovarian Metastasis of Gastric Cancer].

BACKGROUND: Ovarian metastasis of gastric cancer is thought to be less sensitive to chemotherapy.

METHODS: The subjects of this retrospective study were 15 gastric cancer patients with ovarian metastasis treated with first-line chemotherapy between January 1998 and April 2015. Response to chemotherapy was compared between ovarian metastasis and other measurable lesions; progression free survival(PFS), post progression survival(PPS), and overall survival(OS)were compared among the patients showing disease progression only at the ovary(group A), only at lesions other than the ovary(group B), and at both sites(group C).

RESULTS: The patient characteristics were as follows: median age 58 years(range 34-79); performance status 0/1, 4/11; histology of diffuse/intestinal type, 15/0; unilateral/bilateral ovarian metastasis, 5/10; metastasis to the perito- neum/lymph node/bone/pleura, 15/5/2/1; and chemotherapy regimen with S-1+cisplatin/S-1/methotrexate+5-fluorour- acil(5-FU)/5-FU, 9/3/2/1. Partial response/stable disease/progressive disease were obtained in 1/11/3 patients, respectively. In 5 patients having measurable lesions in the ovary and lymph nodes, the median of the largest decrease in size after chemotherapy was 2.8%(range -8.2 to 31.7)at the ovary and 39.4%(range 5.4 to 75.4)at the lymph nodes(p=0.018). The number of patients in the groups A/B/C who experienced disease progression were 6/5/4, respectively; there were no differences in PFS(median 8.6/6.3/7.3months, respectively). Group A showed the longest PPS and OS compared to group B and C(median OS 19.0/9.1/13.8 months and PPS 11.4/4.3/2.5 months, respectively).

CONCLUSION: Compared with other metastatic sites, our findings suggest that ovarian metastasis of gastric cancer may show less chemo-response; however, its progression may have a smaller impact on survival.