What Exactly Is Active Surveillance?

Think of active surveillance as the quiet guardian of prostate cancer care. No alarms, no rushing about, just a steady cycle of checks to ensure the cancer remains exactly where it has promised to stay: localised, low-risk and uninterested in adventure.

It is recommended for men whose PSA levels sit politely within the “not-too-worrying” range (<10ng/ml), whose Gleason scores whisper “low grade” (Gleason score = 6), and whose MRIs reveal no plans of mischief beyond the prostate’s borders. In other words: men whose cancer is present, but not causing trouble¹.

This approach stands in contrast to immediate treatment, with all its potential side-effects, and also to watchful waiting, which is gentler still and aimed at men for whom curative treatment is unlikely to be necessary.¹

Active surveillance occupies the delicate middle ground. It keeps curative treatment on standby while sparing patients the side-effects of surgery, chemotherapy or radiotherapy unless truly needed. A considered compromise, if you will, though one backed by compelling science.

Why Risk Groups, CPG and Gleason Matter

Low-risk prostate cancers earn their reputation not by charm, but by biology. A Gleason score of 6, for instance, signals that the cancer cells still resemble their well-behaved prostate neighbours; they lack the chaotic architecture that marks more aggressive disease.² Similarly, the Cambridge Prognostic Groups (CPG) help classify cancers according to how likely they are to grow or spread, with CPG 1 and 2 tumours being the least inclined toward misadventure.³ And then there is PSA, that quietly informative blood marker whose gentle rise (or reassuring stability) provides clinicians with an ongoing clue about the cancer’s behaviour.⁴ Together, these tools allow clinicians to distinguish the slow, orderly cancers — the ones quite happy to stay put — from their more unruly counterparts. 

Watchful Waiting vs Active Surveillance

While active surveillance is the diligent, note-taking sentinel of prostate cancer care, watchful waiting is its more relaxed, feet-up-on-the-sofa cousin. The two are often mentioned in the same breath, yet they serve quite different purposes. Watchful waiting is typically reserved for older men or those with other health conditions, where the aim is comfort rather than cure. It involves fewer tests, far less medical choreography and only steps in with treatment if troublesome symptoms appear. Where active surveillance keeps an attentive eye on even the subtlest cellular mischief, watchful waiting simply checks in now and then to ensure the cancer isn't causing bother. Both approaches have their place, but they operate at very different tempos.^1,5,6

The Science Behind the Stillness

Why, one might ask, is this calm so clinically acceptable?

Because many low-risk prostate cancers are slow. Very slow.⁷ The sort of tumours that saunter rather than sprint, and may never cause symptoms at all. With regular monitoring, clinicians can detect any sign of change long before danger arrives, and step in with curative treatment.¹

In fact, studies have shown that outcomes for men on active surveillance are remarkably similar to those who undergo immediate treatment, provided the monitoring is diligent.^8,9 

What Does Active Surveillance Actually Involve?

The approach involves a number of tests, all working together to ensure the cancer stays exactly where it ought to:^1,6

• PSA tests every 3–4 months 
• MRI scans providing exquisite detail on whether the tumour remains honourably behaved
• Digital rectal exams although these are not always required
• Repeat biopsies when scans or PSA suggest a change

Should anything begin to stir, a rising PSA, a shift in Gleason pattern, an MRI that suggests a change, treatment is promptly brought into play. The patient is never abandoned to chance.

This is, in every way, active surveillance. Emphasis on active.

The Emotional Weight of “We’re Watching”

Of course, even the most elegantly designed clinical plan must contend with the human mind, an organ brilliant at catastrophising when given half a chance.

To be told “you have cancer” and then, in the next breath, “but we won’t treat it yet” can feel contradictory. Some men may embrace the reprieve; others may feel a subtle pressure of waiting, watching, wondering.

This is where communication becomes medicine in its own right. Patients need to understand why they are perfect candidates for surveillance, what will trigger a change of plan, and that curative treatment is ready and available should the cancer awaken from its slumber. Many find comfort in counselling, peer support or simply a clinician who explains things with unhurried clarity.

Re-Framing Success in Cancer Care

Cancer care has a long history of equating success with aggressive action: bold treatments, immediate interventions, visible warfare. Active surveillance disrupts that narrative entirely.

Here, success is measured differently:^1,6

• Avoiding side-effects until (and if) treatment is truly needed
• Preserving sexual, urinary and bowel function for as long as possible
• Enabling men to live well now
• Intervening only when the clinical evidence raises its hand

But to help patients and families embrace this more nuanced definition, we must communicate carefully.

That means:

• Reinforcing that monitoring is not “giving up” but the refined option
• Explaining benefits without minimising risks
• Using language that respects diversity, values, fear and dignity
• Championing a “right treatment, right time” philosophy

When done well, such communication restores confidence, reduces anxiety and reframes surveillance as a modern hallmark of high-quality care, not a consolation prize.

Conclusion: The Confidence of Careful Surveillance

Active surveillance is not indecision. It is not delay. It is a confident, compassionate response to a cancer that demands thoughtfulness rather than haste.

For suitable men, it offers the chance to live fully today, tomorrow and for many years without the immediate burdens of surgery or radiotherapy. For those of us tasked with communicating these pathways, it offers a rich and necessary narrative: one that values nuance, honours patient autonomy and champions care tailored to the individual rather than the tumour alone.

A gentler form of cancer care, perhaps — but no less powerful for its restraint.

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References: 

1. Greater Manchester Combined Authority. Proposed Revision to Active Surveillance Guidelines. Available at: https://gmcancer.org.uk/wp-content/uploads/2021/10/paper-3_gm-active-surveillance-protcol-v7.pdf 
2. Cancer Research UK. Grade Groups for Prostate Cancer. Available at: https://www.cancerresearchuk.org/about-cancer/prostate-cancer/stages/grades 
3. Gnanapragasam VJ, Bratt O, Muir K, et al. The Cambridge Prognostic Groups for improved prediction of disease mortality at diagnosis in primary non-metastatic prostate cancer: a validation study. BMC Med. 2018;16(1):31.
4. National Cancer Institute. Prostate-Specific Antigen (PSA) Test. Available at: https://www.cancer.gov/types/prostate/psa-fact-sheet 
5. Parker C, Castro E, Fizazi K, et al. Prostate cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol. 2020;31(9):1119-1134. 
6. National Institute for Health and Care Excellence. Prostate cancer: diagnosis and management. Available at: https://www.nice.org.uk/guidance/ng131/chapter/Recommendations 
7. National Library of Medicine. Localized prostate cancer: Learn More – Low-risk prostate cancer: Active surveillance or treatment? Available at: https://www.ncbi.nlm.nih.gov/books/NBK487255/ 
8. Newcomb LF, Schenk JM, Zheng Y, et al. Long-Term Outcomes in Patients Using Protocol-Directed Active Surveillance for Prostate Cancer. JAMA. 2024;331(24):2084-2093. 
9. Hayes JH, Ollendorf DA, Pearson SD, et al. Active surveillance compared with initial treatment for men with low-risk prostate cancer: a decision analysis. JAMA. 2010;304(21):2373-2380.