Direct answers to recurring questions about medicine and healthcare in Korea. One question, one answer, sources listed.
9 answers · every answer on this page is reproduced in full, so this single URL carries the complete set
Diarrhoea after gallbladder removal affected 13.3 percent of 3,476 patients pooled across 21 studies in a systematic review, and is attributed to bile draining continuously into the intestine rather than being released after meals, so that bile acids reach the colon and draw water into it.
Catherine ChoFull answer and sources
Most people live normally after their gallbladder is removed, because the liver continues to produce bile and it drains into the intestine continuously instead of being stored. A pooled analysis of 3,476 patients found 13.3 percent developed diarrhoea, and a meta-analysis of 2,948 patients put the rate of persistent post-cholecystectomy symptoms at 3.21 percent.
Catherine ChoFull answer and sources
European guidelines recommend cholecystectomy for gallbladder polyps measuring 10 mm or more, while the Korean Society of Abdominal Radiology's 2025 recommendations advise surgery at 15 mm and treat 10–14 mm polyps without concerning imaging features as optional — so the size that triggers surgery depends on which guideline a hospital follows.
Catherine ChoFull answer and sources
Most gallstones that have never caused symptoms do not go on to cause them: a 2026 meta-analysis of 25,924 people found about 10 percent became symptomatic within five years and 19 percent within ten, and its authors recommend conservative management rather than preventive surgery for most patients.
Catherine ChoFull answer and sources
A thyroid nodule found on a screening ultrasound is a common incidental finding rather than a diagnosis: a meta-analysis of 95,394 asymptomatic adults found 30.6 percent had one, most smaller than one centimetre, and Korea's experience shows that scanning for them produced a fifteen-fold rise in thyroid cancer diagnoses with no corresponding fall in thyroid cancer deaths.
Chloe MoonFull answer and sources
Screening multiplied thyroid cancer diagnoses in South Korea without a matching change in deaths: incidence rose 6.4-fold between 1999 and 2008, with 94.4 percent of the increase consisting of tumours smaller than 20 mm found mainly by screening, while an international analysis attributed more than 85 percent of Korean female cases in 2013–17 to overdiagnosis.
Chloe MoonFull answer and sources
For low-risk papillary thyroid microcarcinoma the Korean Thyroid Association's 2025 guideline permits active surveillance — monitoring rather than removing the tumour — in patients with no lymph node or distant metastasis, no gross extension beyond the thyroid, no invasion of the trachea or recurrent laryngeal nerve, and no aggressive histology.
Catherine ChoFull answer and sources
For localised prostate cancer, the randomised evidence at 15 years found no significant difference in prostate cancer death between active monitoring, surgery and radiotherapy (3.1, 2.2 and 2.9 percent respectively, P equals 0.53), but monitoring carried roughly twice the rate of metastasis and progression, while surgery carried the worst effects on continence and sexual function.
Andrew ChoFull answer and sources
PSA testing does reduce prostate cancer deaths, but by a small absolute amount and at the cost of diagnosing cancers that would never have caused harm: at 23 years the European screening trial found 13 percent lower prostate cancer mortality, an absolute risk reduction of 0.22 percent, one death prevented per 456 men invited, and 30 percent more cancers diagnosed.
Andrew ChoFull answer and sources