Purpose: To study the frequency, timing, and associations of thoracic metastases in advanced (stage III and IV) high-grade serous ovarian cancer (HGSC) to help optimize the use of cross-sectional chest imaging.
Materials and methods: This institutional review board-approved retrospective study with waived informed consent included 186 consecutive patients with pathologically proven advanced HGSC after primary cytoreduction (mean age ± standard deviation, 60 years ± 9.7) who underwent imaging at our tertiary cancer institution from January 2012 to December 2012 with at least 1 year of follow-up, unless there was thoracic metastasis or death. Electronic medical records and all available imaging studies were reviewed to record patient and tumor characteristics, frequency and timing of abdominal and thoracic metastases, and visibility of the first thoracoabdominal metastasis on abdominal images. Patient and tumor characteristics associated with thoracic metastases were studied by using univariate and multivariate Cox proportional analysis.
Results: After median follow-up of 57 months (interquartile range [IQR], 38-93), 175 patients (94%) developed metastatic disease; each had abdominal disease, and 76 (41%) had thoracic metastases. The first thoracoabdominal metastasis was visible on abdominal images in all 175 patients. The thoracic metastasis-free interval was longer than the abdominal disease-free interval (median, 85 months [IQR, 28-131] vs 14 months [IQR, 7-27], respectively; P < .0001). Presence of disease on abdominal images (hazard ratio, 2.56; 95% confidence interval: 1.35, 4.76) was the only factor independently associated with thoracic metastases.
Conclusion: Thoracic metastases in advanced HGSC rarely occur before abdominal disease, and first thoracoabdominal metastases are invariably visible on abdominal images. Therefore, cross-sectional chest imaging may be deferred until development of abdominal disease, with minimal risk of missing thoracic metastases.