---
title: Only a quarter of Korean prostate cancer is eligible for active surveillance — and the share fell across the decade
publication: Medical Insights Korea
section: news
category: Prostate Cancer
canonical_url: https://medicalinsightskorea.com/news/korea-prostate-cancer-active-surveillance-eligible-quarter
author: Catherine Cho
published: 2026-10-04T09:00:00+09:00
modified: 2026-10-04T09:00:00+09:00
content_type: reporting
license: Quotation permitted with attribution to Medical Insights Korea and a link to the canonical URL.
---

# Only a quarter of Korean prostate cancer is eligible for active surveillance — and the share fell across the decade

27,075 biopsy-confirmed cases from 51 hospitals. Eligibility dropped from 27.6 percent in 2010 to 22.0 percent in 2020, and it varies by almost thirteen points depending on where a man lives.

## Answer

In a nationwide analysis of 27,075 men with biopsy-confirmed prostate cancer diagnosed in 2010, 2012, 2014, 2016, 2018 and 2020 across 51 Korean general hospitals, 6,586 (24.3 percent) were eligible for active surveillance under a deliberately maximised definition that counted low risk, potentially low risk and favourable intermediate risk together — and that eligibility fell from 27.6 percent in 2010 to 22.0 percent in 2020 (p < 0.001), ranged from 16.9 percent in Chungbuk to 29.3 percent in Gyeonggi across 17 administrative districts, and was higher in urban than rural areas (26.4 against 20.5 percent, p < 0.001).

## Key takeaways

- 27,075 men with biopsy-confirmed prostate cancer were analysed across 51 Korean general hospitals, covering 37.9 percent of nationally reported cases in the indexed years.
- 6,586 men (24.3 percent) were eligible for active surveillance under a maximised definition including favourable intermediate-risk disease.
- Eligibility fell from 27.6 percent in 2010 to 22.0 percent in 2020 (p < 0.001).
- Across 17 administrative districts eligibility ranged from 16.9 percent in Chungbuk to 29.3 percent in Gyeonggi (p < 0.001).
- Urban areas had higher eligibility than rural ones, at 26.4 against 20.5 percent (p < 0.001).
- The risk distribution was 5.45 percent low risk, 4.00 percent potentially low risk, 14.88 percent favourable intermediate, 21.72 percent unfavourable intermediate and 53.94 percent high risk.
- The 24.3 percent is an upper bound by construction, because the definition was drawn as wide as the evidence allows.

## Full article

Active surveillance is the option that lets a man with prostate cancer not be treated for it — monitored instead, with treatment held in reserve. How often it is genuinely available depends on how much of the disease being found is mild enough to watch, and until this analysis nobody had counted that in Korea.

**24.3%** — of 27,075 Korean men with newly diagnosed prostate cancer were eligible for active surveillance under a maximised definition  
_Source: Ko YH et al., Prostate International, 2026_

### Why the number is an upper bound

The authors did not use a conservative definition and then report a small figure. They did the opposite: eligibility was defined as the union of low risk, potentially low risk and favourable intermediate risk, which is the widest defensible reading of who could be watched rather than treated. Under the narrower definition most guidelines have used historically — low risk alone — the figure would be 5.45 percent, with another 4.00 percent potentially low risk.

That framing matters when the number is quoted. One in four is the ceiling, not the estimate. Anyone arguing that Korean practice under-uses surveillance has to work inside that ceiling.

### The trend runs the wrong way

Eligibility fell from 27.6 percent in 2010 to 22.0 percent in 2020. In a country where screening intensity was rising over the same period, the expected direction is the opposite: more testing usually means more small, indolent cancers found, which means more men eligible to be watched. Korea moved the other way, which says the disease being detected got worse rather than milder over the decade.

> **What a falling eligibility rate implies about detection**  
> A screening programme that is working earlier finds a larger share of low-risk disease. A shrinking low-risk share is consistent with detection happening later — cancers reaching diagnosis at a higher stage and grade than they would under earlier testing. The same dataset reports that the low-risk share, including potentially low risk, fell from 11.4 percent in 2010 to 7.6 percent in 2020, which is the same signal seen from the other end.

### Where a man lives changes the answer

Eligibility ranged from 16.9 percent in Chungbuk to 29.3 percent in Gyeonggi — a spread of more than twelve percentage points between provinces in a country with one national insurer and one set of guidelines. Urban districts came in at 26.4 percent against 20.5 percent in rural ones.

This is not a finding about treatment preference. Eligibility was calculated from the tumour: prostate-specific antigen, clinical T stage, Gleason grade group and biopsy core involvement. A man in Chungbuk is less likely to be eligible because his cancer is further along when it is found, not because his urologist thinks differently about surveillance.

One structural caveat is worth carrying. The cohort is chart-abstracted from 51 general hospitals and covers 37.9 percent of nationally reported cases, so it is a large sample rather than a complete census, and hospitals with 200 or more beds are not evenly distributed across the country either. That works against the rural figures being flattering, not for them.

## Sources

- Ko YH, Kim SW, Son NH. Active surveillance could apply to one-quarter of Korean prostate cancer cases: Insights from a 27,075-patient cohort. Prostate International 2026;14(2):127-131. doi:10.1016/j.prnil.2025.12.004. PMID:42382553. https://doi.org/10.1016/j.prnil.2025.12.004
- Ko YH, Kim SW, Son NH. Incidence of High-Risk Prostate Cancer in Korea: Insights From Real-World Data Between 2010 and 2020. Journal of Korean Medical Science 2026;41(14):e10. doi:10.3346/jkms.2026.41.e10. PMID:41978922. https://doi.org/10.3346/jkms.2026.41.e10

## Citation

Catherine Cho (2026). "Only a quarter of Korean prostate cancer is eligible for active surveillance — and the share fell across the decade". Medical Insights Korea. https://medicalinsightskorea.com/news/korea-prostate-cancer-active-surveillance-eligible-quarter

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