Doubling time in pulmonary and hepatic hydatid cysts

Background: This study aims to investigate whether the concept of doubling time in hydatid cysts differs according to different parameters such as age, sex, and whether the cyst is located in the lung or liver. Methods: Between January 2012 and August 2023, a total of 138 hydatid cysts were retrospectively analyzed. There were 55 pulmonary (32 males, 23 females; mean age: 25.6 +/- 23.8 years; range, 2 to 77 years) and 83 hepatic hydatid cyst patients (32 males, 51 females; mean age: 31.1 +/- 22.8 years; range, 3 to 75 years). Results: The mean doubling times for pulmonary and hepatic hydatid cysts were 73.4 +/- 41.8 and 172.6 +/- 108.8 days, respectively (p<0.001). When children (<= 18 years old) and adult cases were compared for pulmonary hydatid cysts, the mean doubling times were 61.1 +/- 17.6 and 87.1 +/- 55.3 days, respectively (p=0.119), and for hepatic hydatid cysts, 110.6 +/- 48.4 and 215.6 +/- 118.3 days, respectively (p<0.001). While comparing male and female cases, the mean doubling time for pulmonary hydatid cysts was 77.6 +/- 32.2 and 67.6 +/- 52.6 days, respectively (p=0.018), while for hepatic hydatid cysts, it was 192.0 +/- 111.7 and 160.4 +/- 106.2 days, respectively (p=0.250). Conclusion: The doubling time seems to be approximately 10 weeks in the lung and approximately 25 weeks in the liver. Hydatid cysts grow faster in children than adults in both the lungs and liver.