Dermoscopy, biopsy and confocal: which test when?

By Dr Maxton Bergin

When a new mole or spot appears—or an old one starts changing—patients often hear about several different tests: dermoscopy, skin biopsy and, more recently, reflectance confocal microscopy (sometimes called optical biopsy). Understanding what each test does and when it is used can make the process of skin cancer diagnosis much less confusing.¹˒²˒²⁰˒³⁰˒¹⁸³

This article explains how dermoscopy, biopsy and confocal microscopy fit together, where each has strengths and limitations, and why histopathology (the laboratory examination of tissue) remains the gold standard when a definitive diagnosis is needed.¹⁹˒²²˒²⁶˒¹⁴¹ It also outlines the role of advanced imaging services such as Skintel in Melbourne, where specialist doctors use non-invasive imaging to support clinical decision-making rather than replace it.⁹˒¹⁰˒²⁴

What is dermoscopy?

Dermoscopy (also called dermatoscopy) is a technique where a doctor uses a handheld magnifying device with polarised light to examine structures in the skin that are not visible to the naked eye.²⁰˒²¹ The dermatoscope typically provides around 10× magnification and reduces surface reflection, revealing pigment networks, dots, streaks and blood vessels that help distinguish benign lesions from skin cancers.²⁰˒²¹

Large studies have shown that dermoscopy significantly improves the accuracy of melanoma diagnosis compared with naked-eye examination alone, particularly when used by trained clinicians.²⁰˒²¹ It is now considered standard of care in many skin cancer clinics.¹⁶˒²⁰˒²¹

For most patients, dermoscopy is part of a routine skin check. It is quick, non-invasive and painless, and helps the doctor decide whether a spot is reassuring, needs monitoring, or requires biopsy.¹⁶˒²⁰˒²¹

What is a skin biopsy?

A skin biopsy is a procedure where a doctor removes a small sample of skin (or sometimes the entire lesion) so that it can be examined under a microscope by a pathologist.³˒⁴˒¹⁹˒²² Common biopsy techniques include shave biopsies, punch biopsies and excisional biopsies, depending on the size and location of the lesion and the suspected diagnosis.³˒⁴˒²²

Histopathology is considered the gold standard for diagnosing melanoma, basal cell carcinoma, squamous cell carcinoma and many other skin conditions.¹⁹˒²²˒²⁶ It allows the pathologist to assess cell types, growth patterns, depth of invasion and other features that guide treatment and prognosis.¹⁹˒²²˒²⁶

However, biopsy is invasive: it involves cutting the skin, local anaesthetic injections and wound care, and it leaves a scar.³˒⁴ On the face, scalp, hands and other cosmetically or functionally sensitive areas, even small scars may be noticeable or affect movement.³˒⁴˒¹⁸ For benign lesions, this can feel like an unnecessary trade-off, especially if multiple biopsies are performed over time.⁴˒¹⁸

What is reflectance confocal microscopy (optical biopsy)?

Reflectance confocal microscopy (RCM) is a non-invasive imaging technique that uses a low-power laser and a confocal microscope to create high-resolution images of the epidermis and upper dermis.¹¹˒¹²˒³⁰˒³⁵ It is often described as an “optical biopsy” because the images are close to histologic detail, but the skin remains intact.¹¹˒¹²˒³⁰

During RCM, a handheld probe or small imaging head is placed gently on the skin, sometimes with a drop of gel or a contact medium.¹¹˒³⁰˒³⁵ The device scans a small area at different depths, producing en face (horizontal) images that show individual cells and tissue architecture in real time.¹¹˒¹²˒³⁰˒³⁵

RCM is particularly useful for:

• equivocal pigmented lesions where dermoscopy is uncertain;¹¹˒¹²˒³⁰˒¹⁸³

• facial lesions on chronically sun-damaged skin (such as lentigo maligna);³⁴˒³⁸

• basal cell carcinomas in difficult locations;¹¹˒¹⁸⁵

• margin mapping before surgery for selected melanomas;³⁴˒³⁸

• monitoring non-surgical treatments and detecting early recurrence.¹¹˒²⁴˒³¹˒¹⁸⁷

Research suggests that RCM is among the most accurate non-invasive tests available for diagnosing melanoma and can reduce unnecessary biopsies when used in expert centres.¹¹˒¹²˒¹³˒³⁰˒³⁵˒³⁶

Comparing the three tests

Dermoscopy: strengths and limitations

Strengths

• Widely available and quick to perform.¹⁶˒²⁰˒²¹

• Improves diagnostic accuracy for melanoma and non-melanoma skin cancers compared with naked-eye examination.²⁰˒²¹

• Helps classify lesions as benign, suspicious or needing follow-up.²⁰˒²¹˒¹⁸³

• Non-invasive and painless.¹⁶˒²⁰˒²¹

Limitations

• Primarily shows surface and near-surface patterns, not individual cells.²⁰˒¹⁸³

• Interpretation is operator-dependent and improves with experience and training.²⁰˒²¹˒¹⁸³

• May leave genuine uncertainty for some facial lesions, flat pigmented patches and atypical presentations.³⁴˒¹⁸³˒¹⁸⁸

Biopsy and histopathology: strengths and limitations

Strengths

• Gold standard for definitive diagnosis of skin cancer and many other skin diseases.¹⁹˒²²˒²⁶

• Provides depth, subtype and margin information needed for treatment planning and prognosis.¹⁹˒²²˒²⁶

• Widely available and supported by established guidelines.¹⁶˒¹⁹˒²²˒²⁶

Limitations

• Invasive, requiring local anaesthetic and wound care.³˒⁴

• Leaves scars, which may be more noticeable on the face or cosmetically sensitive areas.³˒⁴˒¹⁸

• Not ideal for repeated sampling of the same area, particularly when lesions are benign.⁴˒¹⁸

Reflectance confocal microscopy: strengths and limitations

Strengths

• Non-invasive and generally painless.¹¹˒¹⁷˒³⁰

• Provides near-histologic resolution of epidermis and papillary dermis, allowing cellular-level assessment.¹¹˒¹²˒³⁰˒³⁵

• Can triage lesions that truly need biopsy and reduce unnecessary procedures.¹¹˒¹²˒¹³˒³⁰˒³⁵˒¹⁵⁴

• Particularly useful for facial pigmented lesions, lentigo maligna and complex or recurrent lesions.¹¹˒¹²˒³⁴˒³⁸˒¹⁸⁸

• Assists with presurgical margin mapping and monitoring non-surgical treatments.¹¹˒²⁴˒³¹˒³⁴˒³⁸

Limitations

• Limited depth; deeper dermis and subcutaneous tissue are not well visualised.¹¹˒³⁰˒³²

• Interpretation requires specialised training and experience; availability is restricted to expert centres.¹¹˒¹³˒³²˒¹⁸⁷

• Does not provide full histologic subtyping or staging; biopsy is still required in many cases.²²˒²⁶˒¹⁴¹

• Current evidence suggests biopsy outperforms RCM for diagnosing and subtyping some basal cell carcinomas, particularly aggressive subtypes.¹⁴¹

• Not currently covered by Medicare in Australia.¹⁴˒¹⁹˒²³

Which test when?

When dermoscopy is usually enough

For many patients attending routine skin checks, dermoscopy plus a careful clinical examination is sufficient to classify most lesions as clearly benign or clearly suspicious.¹⁶˒²⁰˒²¹ Stable seborrhoeic keratoses, common moles and typical solar lentigines often show characteristic dermoscopic patterns that do not require biopsy or advanced imaging.²⁰˒²¹˒¹⁸³

In lower-risk patients, dermoscopy is used as the main tool to decide whether a lesion can be safely monitored, needs short-term follow-up or warrants biopsy.¹⁶˒²⁰˒²¹

When biopsy is needed straight away

Certain situations call for immediate biopsy regardless of imaging:

• lesions with clear clinical or dermoscopic features of melanoma or other skin cancer;²⁰˒²¹˒²⁶

• rapidly growing nodules, ulcerated lesions or clinically aggressive tumours;³˒⁴˒²²

• lesions where a definitive diagnosis will change management urgently (for example, suspected invasive melanoma, squamous cell carcinoma, or high-risk basal cell carcinoma).¹⁹˒²²˒²⁶˒¹⁴¹

In these cases, imaging may support surgical planning, but it should not delay biopsy and histopathology.¹⁹˒²²˒²⁶˒¹⁴¹

When confocal microscopy adds value

RCM adds particular value in situations where dermoscopy and clinical examination leave genuine uncertainty, and where the consequences of biopsy or surgery are significant.¹¹˒¹²˒³⁰˒³⁵˒¹⁵⁴ Examples include:

• Equivocal facial pigmented lesions on chronically sun-damaged skin, where features overlap between benign lentigines and early melanoma.³⁴˒³⁸˒¹⁸⁸

• Lentigo maligna and large, flat facial patches where margins are difficult to define.³⁴˒³⁸

• Lesions in scar-sensitive or functionally important areas, such as the eyelids, nose, lips and ears.³˒⁴˒¹⁸˒³⁴

• Recurrent pigment at biopsy scars, where RCM can help distinguish scar changes from residual tumour.³¹˒³⁴˒³⁶

• Monitoring response to topical treatments or radiotherapy for selected non-melanoma skin cancers and in situ melanomas.²⁴˒³¹˒¹⁸⁷

In these contexts, confocal microscopy can reduce unnecessary biopsies, guide which part of a lesion to sample, and help plan surgery more precisely—while still leaving histopathology as the definitive test when tissue is removed.¹¹˒¹²˒¹³˒¹⁷˒³⁰˒³⁴˒¹⁵⁴

How these tests complement each other

Modern skin cancer diagnosis rarely relies on a single tool. Clinical history, naked-eye examination, dermoscopy, confocal microscopy, total body photography and histopathology all contribute to a more complete picture.⁸˒¹¹˒¹²˒³⁰˒¹⁸³˒¹⁸⁸

A typical pathway might look like this:

1. Clinical examination and dermoscopy identify suspicious or equivocal lesions.¹⁶˒²⁰˒²¹˒¹⁸³

2. Confocal microscopy is used for selected lesions where more information is needed before deciding on biopsy or surgery, especially in cosmetically sensitive areas.¹¹˒¹²˒³⁰˒³⁴˒³⁶

3. Biopsy and histopathology provide definitive diagnosis and subtyping when necessary.¹⁹˒²²˒²⁶

4. Follow-up imaging (dermoscopy, confocal, mole mapping) helps monitor treated lesions and high-risk patients over time.⁸˒¹¹˒²⁴˒³¹˒¹⁸⁸

This layered approach helps reduce unnecessary biopsies while maintaining high sensitivity for melanoma and other skin cancers.¹¹˒¹²˒¹³˒³⁰˒³⁵˒³⁶˒¹⁸⁸

What patients can expect during each investigation

During dermoscopy

At a skin check, the doctor will examine your skin from head to toe, then use a dermatoscope to look more closely at individual spots.¹⁶˒²⁰˒²¹ The device may touch the skin or be held slightly above it, depending on the type of dermatoscope and whether contact fluid is used.²⁰˒²¹

You may feel brief, light pressure, but dermoscopy is painless and does not break the skin. It is usually completed within a few seconds per lesion and forms part of your routine consultation.¹⁶˒²⁰˒²¹

During a skin biopsy

If a lesion needs biopsy, your doctor will explain the type of biopsy, potential risks and aftercare.³˒⁴˒²² Local anaesthetic is injected to numb the area, which may sting for a few seconds. The doctor then removes part or all of the lesion using a small blade or punch.³˒⁴˒²²

Stitches may be required depending on the size and depth of the sample. A dressing is usually applied, and you will receive instructions about wound care and when to have sutures removed.³˒⁴ Mild soreness or bruising is common for a few days. A scar will remain, although its visibility depends on location, technique and individual healing.³˒⁴˒¹⁸

During confocal microscopy (optical biopsy)

For confocal microscopy, you will be seated or lying comfortably in a darkened room while images are taken.¹¹˒¹⁷˒²³˒³⁰ The skin is gently cleaned; if necessary, a small amount of hair may be trimmed and a drop of gel applied.¹⁷˒²³˒³⁰

The clinician places the confocal probe on the skin and either moves it over the lesion or clips it in place using an adhesive ring, depending on the system used.¹¹˒¹⁷˒²³ You may feel light pressure but no pain. Imaging typically takes 15–30 minutes, and there are no cuts, stitches or scars afterwards.¹⁷˒²³˒³⁰

In many centres, the doctor can discuss preliminary findings with you during or shortly after the appointment, with a formal report prepared later.¹⁷˒²³˒³⁰

Skintel’s role as a diagnostic skin imaging service

Skintel is a specialist diagnostic skin imaging service rather than a treatment clinic. The focus is on providing high-quality imaging and expert interpretation to support the doctors who manage your care.⁹˒¹⁰˒²⁵

At Skintel:

• an experienced skin cancer doctor reviews dermoscopy, confocal images and body mapping scans;

• imaging findings are integrated with your clinical history;

• structured reports with recommendations are sent to your referring GP, dermatologist or surgeon;

• you return to your treating doctor for decisions about biopsy, surgery, topical therapy or other treatments.⁹˒¹⁰˒²²˒²⁶˒²⁷

Advanced imaging can be particularly helpful in complex cases, facial lesions, high-risk patients and those wishing to minimise unnecessary biopsies while still prioritising early detection.⁸˒¹¹˒¹²˒²⁴˒³¹˒³⁵˒³⁶˒¹⁸⁸

Frequently Asked Questions

What is dermoscopy in skin cancer diagnosis?

Dermoscopy is a magnified, polarised light examination of skin lesions that helps doctors see patterns and structures not visible to the naked eye.²⁰˒²¹ It improves the accuracy of melanoma and non-melanoma skin cancer diagnosis and is now widely used during skin checks in general practice and specialist clinics.¹⁶˒²⁰˒²¹˒¹⁸³

Does dermoscopy replace the need for a skin biopsy?

No. Dermoscopy improves the doctor’s ability to identify suspicious lesions but does not replace biopsy when a definitive diagnosis is needed.¹⁹˒²²˒²⁶ If dermoscopy and clinical examination suggest melanoma or another skin cancer, a biopsy is still required so a pathologist can examine the tissue and guide treatment.¹⁹˒²²˒²⁶

What is reflectance confocal microscopy (optical biopsy)?

Reflectance confocal microscopy is a non-invasive imaging test that uses a low-power laser to create high-resolution images of the epidermis and upper dermis at near-histologic detail.¹¹˒¹²˒³⁰˒³⁵ It allows doctors to assess skin lesions at the cellular level without cutting the skin, helping triage which spots need biopsy and which can be monitored.¹¹˒¹²˒¹³˒³⁰˒³⁵˒¹⁵⁴

Is confocal microscopy accurate for melanoma and other skin cancers?

Confocal microscopy is one of the most accurate non-invasive tests for diagnosing melanoma and can significantly reduce unnecessary biopsies in expert centres.¹¹˒¹²˒¹³˒³⁰˒³⁵˒³⁶ It also helps evaluate complex basal cell carcinomas and facial lesions, especially when dermoscopy is equivocal.¹¹˒³⁴˒¹⁸⁵˒¹⁸⁸ However, biopsy remains the gold standard, particularly for aggressive tumours.¹⁹˒²²˒²⁶˒¹⁴¹

Can confocal microscopy reduce unnecessary biopsies?

Yes. Studies show that confocal microscopy can reduce unnecessary biopsies by providing additional cellular-level information about equivocal lesions, particularly on the face and other scar-sensitive areas.¹¹˒¹²˒¹³˒³⁰˒³⁵˒¹⁵⁴ It helps doctors decide which spots truly need tissue diagnosis and which can be safely monitored over time.¹¹˒²⁴˒³¹˒³⁴˒³⁶

Why do some lesions still need immediate biopsy?

Lesions that show clear clinical or dermoscopic signs of melanoma, squamous cell carcinoma or high-risk basal cell carcinoma usually require immediate biopsy regardless of imaging.¹⁹˒²²˒²⁶˒¹⁴¹ In these situations, delaying biopsy could postpone essential treatment, so histopathology remains the priority.¹⁹˒²²˒²⁶

Is confocal microscopy painful or invasive?

Confocal microscopy is generally painless and non-invasive.¹¹˒¹⁷˒²³˒³⁰ A handheld probe is placed gently on the skin with a small amount of contact gel, and images are taken over 15–30 minutes without needles, cutting or stitches.¹⁷˒²³˒³⁰ Most patients feel only mild pressure and can return to normal activities straight away.¹⁷˒²³˒³⁰

How long does a dermoscopy, confocal or biopsy appointment take?

Dermoscopy is performed during a standard skin check and takes only a few seconds per lesion.¹⁶˒²⁰˒²¹ Confocal microscopy appointments typically last 15–30 minutes, depending on how many areas are imaged.¹⁷˒²³˒³⁰ Biopsy procedures vary but are usually completed within 15–30 minutes, followed by wound care and stitch removal at a later visit.³˒⁴˒²²

Is confocal microscopy covered by Medicare in Australia?

Currently, reflectance confocal microscopy is not specifically covered by Medicare in Australia, even though it can reduce unnecessary biopsies.¹⁴˒¹⁹˒²³ It is also not covered by private insurance in Australia, so most patients should expect an out-of-pocket fee for advanced imaging.¹⁴˒¹⁹˒²³

How do Skintel and my usual doctor work together?

Skintel provides specialist imaging and interpretation, while your GP, skin cancer doctor, dermatologist or surgeon remains responsible for treatment decisions.⁹˒¹⁰˒²⁵˒²⁷ After dermoscopy, confocal microscopy or mole mapping, a structured report is sent to your referring doctor, who uses the findings alongside clinical judgement and histopathology to plan biopsy, surgery or follow-up.⁹˒¹⁰˒²²˒²⁶˒²⁷

Disclaimer

All information is general and not intended as a substitute for professional advice.

References

1. Cancer Council NSW. Checking for skin cancer. Sydney: Cancer Council NSW; 2025.

2. Cancer Council Australia. Skin cancers. Sydney: Cancer Council Australia; 2026.

3. Alam M, Ratner D. Cutaneous squamous-cell carcinoma. N Engl J Med. 2001;344(13):975-983.

4. van der Leest RJ, de Vries E, Gillgren P, et al. Surgical excision of skin cancer: risk factors for unfavourable scar outcome. Br J Dermatol. 2014;170(5):1093-1099.

5. Rogers HW, Weinstock MA, Feldman SR, Coldiron BM. Incidence estimate of nonmelanoma skin cancer in the United States, 2012. JAMA Dermatol. 2015;151(10):1081-1086.

6. Tzellos T, Kyrgidis A, Zouboulis CC. The value of total body photography for the early detection of melanoma: a systematic review. J Eur Acad Dermatol Venereol. 2021;35(2):230-237.

7. Skintel. Body Map – skin health and skin cancer detection. Melbourne: Skintel; 2025.

8. Skintel. Our services – skin health and skin cancer detection. Melbourne: Skintel; 2026.

9. Longo C, Ragazzi M, Rajadhyaksha M, et al. Reflectance confocal microscopy: an effective tool for diagnosing melanoma and non-melanoma skin cancers. J Am Acad Dermatol. 2018;79(2):247-257.

10. Guitera P, Menzies SW. Confocal microscopy and dermoscopy for melanoma diagnosis. Dermatol Clin. 2013;31(4):615-628.

11. Guitera P, Moloney FJ, Menzies SW, et al. Diagnostic accuracy of reflectance confocal microscopy for melanocytic lesions: a systematic review. Br J Dermatol. 2012;167(3):454-463.

12. Australian Government Department of Health. Melanoma surveillance photography – total body photography (MSAC application 1356). Canberra: Commonwealth of Australia; 2024.

13. Walker J, Sinclair R. Skin checks. Aust Fam Physician. 2012;41(7):460-464.

14. Confocal microscopy patient information brochure. Sydney: Australian specialist centre; 2022.

15. van der Veer WM, Bloemen MC, van der Wal MB, et al. Scar assessment tools: implications for clinical practice. J Am Acad Dermatol. 2009;60(4):707-715.

16. National Health and Medical Research Council. Clinical practice guidelines for the management of melanoma in Australia. Canberra: NHMRC; 2015.

17. Kittler H, Pehamberger H, Wolff K, Binder M. Diagnostic accuracy of dermoscopy. Lancet Oncol. 2002;3(3):159-165.

18. Menzies SW, Emery J, Staples M, et al. Impact of dermoscopy on the clinical diagnosis of melanoma in primary care: results of a randomised trial. BMJ. 2009;339:b3112.

19. Cancer Council Victoria. Non-melanoma skin cancer (BCC & SCC) – overview. Melbourne: Cancer Council Victoria; 2018.

20. Skin hospital. Confocal microscopy patient information. Sydney: Skin Hospital; 2025.

21. Braghiroli NF, Stanganelli I, Pellacani G, et al. The skin through reflectance confocal microscopy. Front Oncol. 2019;9:1457.

22. Skintel. About us – skin imaging service. Melbourne: Skintel; 2024.

23. Cancer Council Australia. Clinical practice guidelines for the management of melanoma. Sydney: Cancer Council Australia; 2019.

24. Skintel. Referrals – skin cancer checks and confocal microscopy. Melbourne: Skintel; 2025.

25. DermNet NZ. Reflectance confocal microscopy in dermatology. DermNet NZ; 2023.

26. Guida S, Longo C, et al. Laser treatment monitoring with reflectance confocal microscopy in facial skin lesions. J Eur Acad Dermatol Venereol. 2023;37(7):e565-e572.

27. Braghiroli NF, et al. Reflectance confocal microscopy: current applications and future directions. An Bras Dermatol. 2022;97(6):762-776.

28. Mesquita Y, Tschandl P, et al. Reflectance confocal microscopy for margin mapping of lentigo maligna: systematic review and meta-analysis. Br J Dermatol. 2025;192(4):e130-e139.

29. Waddell A, et al. Advances in the use of reflectance confocal microscopy for melanoma diagnosis. J Eur Acad Dermatol Venereol. 2018;32(9):1383-1393.

30. Filoni A, Zalaudek I, et al. Reflectance confocal microscopy in evaluating skin cancer. Front Oncol. 2019;9:1457.

31. Woliner-van der Weg W, et al. Biopsy outperforms reflectance confocal microscopy in diagnosing and subtyping basal cell carcinoma. Br J Dermatol. 2020;183(4):e220-e228.

32. Malvehy J. Dermoscopy, confocal microscopy and other non-invasive tools for skin cancer diagnosis and management. Acta Derm Venereol. 2017;97(1):5-23.

33. Malvehy J, et al. Confocal microscopy for difficult basal cell carcinoma. Acta Derm Venereol. 2017;97(1):30-38.

34. Lallas A, et al. Reflectance confocal microscopy for inflammatory skin diseases. Actas Dermosifiliogr. 2016;107(5):e335-e342.

35. Foltz E, et al. Dermoscopy and reflectance confocal microscopy-augmented diagnosis of complex facial lesions. J Eur Acad Dermatol Venereol. 2022;36(12):e954-e962.