Dive deeper

Open any topic for the full explanation, tables, clinical checkpoints, and references.

Full-length video Where can I learn more about follow-up and prevention after skin cancer?

A complete visual guide

Watch the full explanation on YouTube A complete visual review with the supporting clinical context.
What should a skin-cancer follow-up plan answer?

Direct Answer

Follow-up after skin cancer should have actual dates and a reason for each visit. For most basal cell carcinomas, visits begin every 6 to 12 months. Squamous cell carcinoma follow-up is usually closer during the first two years—often every 3 to 12 months for low-risk disease and every 3 to 6 months for high-risk disease. Melanoma follow-up is determined mainly by stage: yearly skin examination after melanoma in situ, every 6 to 12 months for the first five years after stage IA–IIA melanoma, and every 3 to 6 months at first after higher-stage melanoma with no evidence of disease.[1–6]

The interval is only one part of the plan. Each visit should answer:

  1. Could the treated cancer be returning?
  2. Is there a new, separate skin cancer?
  3. Do the scar, lymph nodes, symptoms, or treatment effects need attention?
  4. Would an examination be enough, or is imaging appropriate?
  5. What should make you call before the next scheduled visit?
What do recurrence, risk, stage, and NED mean?

The Minimum Vocabulary

Recurrence means the treated cancer has returned at the original site, nearby, in a regional lymph node, or elsewhere in the body.

A new primary is a new and separate cancer. A BCC on the forehead two years after a BCC on the shoulder is usually a new primary, not spread from the first tumor.

Risk group describes how likely a cancer is to return or spread based on features such as size, location, depth, growth pattern, nerve involvement, recurrence, and immune status.

Stage describes how far a cancer has progressed. It is especially important in melanoma and in cSCC that has spread beyond the skin.

No evidence of disease, often shortened to NED, means no cancer is detectable after treatment. It does not mean the future risk is zero.

Surveillance is planned follow-up intended to find recurrence, a new primary, or treatment effects early enough to change care.

How does cancer type and risk change follow-up?

Typical Follow-Up by Cancer and Risk

The table below translates current NCCN and American Academy of Dermatology guidance into patient-facing ranges.[1–6] “History and examination” means a focused conversation about symptoms plus an examination matched to the cancer; it does not automatically mean a scan.

Typical Follow-Up by Cancer and Risk
Diagnosis and riskFirst 2 yearsYears 3–5After 5 yearsWhat the visit should emphasizeRoutine imaging when you feel well?
BCCEvery 6–12 monthsEvery 6–12 monthsAt least yearlyTreated site and full skin examinationNo, except selected advanced disease or a specific concern
Low-risk cSCCEvery 3–12 monthsEvery 6–12 monthsYearlyTreated site, full skin; lymph nodes when clinically relevantNo
High-risk cSCCEvery 3–6 monthsEvery 6–12 monthsYearlyTreated site, full skin, regional lymph nodes, neurologic symptomsOnly when risk, findings, or symptoms justify it
Very-high-risk cSCCEvery 3–6 monthsEvery 6 monthsEvery 6–12 months for lifeTreated site, full skin, regional lymph nodes, neurologic symptomsOften individualized to risk, examination, and symptoms
Regional cSCCOften every 2–3 months in year 1, then every 2–4 months in year 2Every 4–6 monthsEvery 6–12 monthsSkin, nodal basin, treatment effects, multidisciplinary surveillanceOften part of an individualized oncology plan
Melanoma stage 0Yearly skin examinationYearly skin examinationYearly for lifeFull skin and regional nodes as indicatedNo
Melanoma stage IA–IIAEvery 6–12 monthsEvery 6–12 monthsYearly skin examination; other visits as indicatedSkin, scar, lymph nodes, symptomsNo routine imaging if asymptomatic
Melanoma stage IIB–IV, NEDEvery 3–6 monthsEvery 3–12 monthsYearly skin examination; other visits as indicatedSkin, scar, nodes, symptoms, treatment effectsMay be considered for a defined period, usually within the first 5 years

How to use this table

Think of each range as a lane, not a promise. A first low-risk cSCC may reasonably sit near the longer end. A recurrent cSCC on the ear in a transplant recipient belongs near the shorter end and may require a more intensive plan. Active advanced melanoma is not a “routine surveillance” situation; its schedule follows the treatment and oncology plan.

The table also separates office visits from imaging. More scans are not automatically better. A scan is useful when the probability of actionable disease is high enough to outweigh false alarms, radiation or contrast exposure, cost, and downstream testing.

Why do the first two years matter most?

Why the First Two Years Often Matter Most

Guidelines place closer visits early because many consequential recurrences appear during that period.

In a four-center study reporting five-year outcomes for 598 cSCC excisions, 40 local or nodal recurrences occurred. Ninety-six percent were detected within two years, and the median time to local recurrence was nine months.7 This study involved surgically treated tumors and does not define the risk for every cSCC. It explains why a high-risk cSCC should not receive a vague “come back sometime next year” plan.

A Danish national cohort followed 25,720 adults with stage IA–IV melanoma for a median of 5.9 years. Overall, 10.6% developed a recurrence; risk varied sharply by stage, and a large share of recurrence in higher-risk stages appeared early.8 This supports closer early follow-up after stage IIB–IV melanoma, not the same scan schedule for every melanoma survivor.

What this means for you: a closer early schedule is not pessimism. It concentrates attention during the period when finding a recurrence may be most likely to change the next step.

How does BCC follow-up usually work?

Basal Cell Carcinoma: Common, Usually Curable, Still Worth Following

Most BCCs are cured with appropriate treatment. Follow-up still matters for two different reasons.

First, BCC can recur, especially when it was recurrent, aggressive, poorly defined, incompletely treated, or located in a high-risk area. In a randomized trial of high-risk facial BCC, 56% of recurrences after treatment of primary tumors occurred more than five years later.11 That trial does not mean everyone needs six-month visits forever. It means a few clean years should not be mistaken for permanent immunity.

Second, a person who has developed one BCC has demonstrated susceptibility to additional keratinocyte cancers. In a prospective cohort that excluded immunocompromised patients, the five-year probability of another BCC or cSCC was 40.7% after a first lifetime tumor and 82.0% after a nonfirst tumor.9

What this means for you: after a routine BCC, 6- to 12-month visits are a reasonable starting point. A history of repeated tumors, an aggressive subtype, recurrence, or immune suppression can justify the shorter end.

How does SCC risk change the calendar?

Squamous Cell Carcinoma: Risk Changes the Calendar

cSCC spans a wide spectrum. A small, well-defined low-risk tumor and a recurrent tumor with deep invasion or nerve involvement should not share one schedule.

Factors that commonly move follow-up toward every three to six months include:

  • recurrence or incomplete prior treatment;
  • larger size, greater depth, poor differentiation, or aggressive growth;
  • perineural invasion, especially clinically significant nerve involvement;
  • high-risk location;
  • rapid growth or poorly defined borders;
  • immune suppression or organ transplantation; and
  • regional lymph-node disease.

The lymph-node examination matters more as risk rises. For a head or neck cSCC, that may include feeling the parotid and neck nodal basins. New numbness, weakness, persistent pain, a growing lump, or a change around the scar should prompt evaluation rather than waiting for the next calendar date.

People with regional cSCC need a multidisciplinary plan. Their schedule is usually measured in months, not years, and may include imaging. The oncology, dermatology, surgical, and radiation teams should make ownership explicit.

How does melanoma stage determine follow-up?

Melanoma: Stage Determines the Follow-Up Plan

Melanoma in situ is confined to the outermost skin layer. After treatment, a yearly lifelong skin examination is a typical starting point because the main ongoing issue is often a new primary melanoma.

For stage IA–IIA melanoma, current guidance generally uses history and examination every 6 to 12 months for five years, then at least yearly skin examination.5,6 Routine imaging is not recommended for a person without symptoms in these stages because false-positive findings and extra procedures can outweigh the chance of finding useful disease.

For stage IIB–IV melanoma with no evidence of disease, closer visits—every 3 to 6 months for two years, then every 3 to 12 months through year five—reflect the higher recurrence risk.5 Selected patients may have cross-sectional imaging and sometimes brain imaging for a defined period. The exact modality and interval depend on stage, treatment, symptoms, and the oncology plan.

Skin surveillance remains important after recurrence-focused imaging stops. In a population-based cohort of 152,811 people treated surgically for a first nonmetastatic melanoma, a second primary melanoma was diagnosed in 3.9% by five years and 6.7% by ten years.10

What this means for you: melanoma follow-up has two clocks. One watches for recurrence according to stage. The other watches for a new melanoma for life.

How should selected rare cancers be followed?

Selected Rare Skin Cancers

Rare tumors should not be forced into the BCC, cSCC, or melanoma schedule. Their biology and evidence base differ, and the published recommendations are often based on expert consensus and retrospective studies rather than randomized trials.

Atypical fibroxanthoma and pleomorphic dermal sarcoma

Atypical fibroxanthoma (AFX) is usually a superficial tumor of chronically sun-damaged skin. Pleomorphic dermal sarcoma (PDS) is related but behaves more aggressively because it extends deeper or shows features such as tumor necrosis, lymphovascular invasion, or nerve invasion.

One specialist guideline recommends clinical follow-up for AFX every 6 months for the first 2 years, then yearly through year 5. PDS generally deserves closer follow-up—often every 3 months for 2 years, then every 6 months through year 5—with examination of regional lymph nodes and selective imaging based on risk.12,13

Patient meaning: make sure your report says AFX or PDS. The names are related, but they should not produce the same follow-up intensity.

Dermatofibrosarcoma protuberans

Dermatofibrosarcoma protuberans (DFSP) is usually slow-growing but can recur locally, sometimes years later. A recent European guideline recommends examination of the primary site every 6 months for the first 3 years, then yearly through year 5 after complete treatment of typical DFSP. Recurrent tumors, narrow margins, fibrosarcomatous change, or other high-risk features can justify local MRI every six months at first and longer surveillance, sometimes through year 10.14

Patient meaning: the follow-up is centered on careful palpation of the treated area. A firm change under or beside the scar deserves review even when the surface looks normal.

Extramammary Paget disease

Extramammary Paget disease (EMPD) often involves genital, perianal, or axillary skin. It can extend beyond what is visible and can be associated with an underlying internal cancer depending on location and tumor type.

Evidence-based guidance recommends close surveillance for at least the first 5 years.15 A common specialist pattern is every 3 to 6 months for the first 3 years, then every 6 to 12 months through year 5, adjusted for invasive disease, margins, nodes, associated internal cancer, and treatment. The visit may involve dermatology, gynecology, urology, colorectal surgery, or oncology.

Patient meaning: a new itch, erosion, thickening, bleeding area, or lump in or near the treated field should not wait for the next routine visit.

Adnexal carcinomas are not one disease

“Adnexal carcinoma” describes cancers arising from sweat, sebaceous, or follicular structures. There is no honest universal interval.

  • Microcystic adnexal carcinoma: expert guidance recommends a clinician familiar with the disease every 6 to 12 months for the first 5 years. Examination should include careful palpation because the tumor can track deeply or along nerves.16
  • Sebaceous carcinoma: the current S1 guideline proposes a risk-adapted schedule of about every 3 months for the first 2 years, every 6 months through year 5, then yearly through year 10, with attention to regional nodes and possible Lynch syndrome when the clinical history suggests it.17
  • Other sweat-gland or follicular carcinomas: the histologic subtype, grade, margins, nerve or vessel involvement, nodal risk, and treatment determine the plan. A dermatologic oncologist, Mohs surgeon, surgical oncologist, or multidisciplinary tumor board may be needed.

Patient meaning: ask for the exact pathology name. “Adnexal carcinoma” by itself is not specific enough to build a surveillance calendar.

What happens at a useful follow-up visit?

What Happens at a Useful Follow-Up Visit?

A useful visit is not just a glance at the scar.

  1. Review the original cancer. The clinician should know the diagnosis, stage or risk group, treatment, margin result, and date.
  2. Examine the treated site. Visual inspection and palpation may identify a surface change or a deeper nodule.
  3. Examine regional lymph nodes when relevant. This is especially important for higher-risk cSCC, melanoma, PDS, sebaceous carcinoma, and selected other rare tumors.
  4. Examine the rest of the skin. A new primary cancer is often more likely than recurrence of a successfully treated low-risk tumor.
  5. Ask about symptoms. Persistent pain, numbness, weakness, a new lump, bleeding, unexplained weight change, cough, headache, or neurologic symptoms are interpreted in context.
  6. Review treatment effects. Eyelid closure, nostril shape, lip movement, sensation, lymphedema, radiation change, graft or flap contour, and systemic-therapy toxicity can all matter.
  7. Update prevention. Ultraviolet exposure, indoor tanning, protective habits, immune suppression, and selected chemoprevention should be reviewed.

Bring a simple cancer timeline. Include the body site, pathology name, treatment, date, and treating clinician. This prevents a repeated tumor from being mistaken for a first tumor and helps different specialists coordinate.

What should I do between visits?

What to Do Between Visits

Professional visits are snapshots. You and a partner can contribute the missing element of time.

Use a consistent self-check routine—often monthly for a person at increased risk—and look for:

  • a new or clearly changing lesion;
  • a spot unlike the rest;
  • recurrent bleeding, crusting, or failure to heal;
  • a new nodule in or beside a scar;
  • persistent pain, tenderness, numbness, or weakness;
  • a rapidly growing lesion; or
  • a new lump in a nearby lymph-node area.

The American Society for Dermatologic Surgery encourages regular self-examination and at least annual professional skin assessment as broad prevention guidance.23 Your cancer-specific schedule may be more frequent.

A phone photograph can document change, but a photograph cannot prove that a lesion is benign. If a change matters, send it through the channel your clinician recommends or arrange an in-person examination. Do not wait for every ABCDE feature, a certain diameter, or the next scheduled visit.

Which prevention steps have evidence?

Prevention That Has Evidence Behind It

Layer ultraviolet protection

Use shade, protective clothing, a broad-brimmed hat, UV-protective sunglasses, and broad-spectrum water-resistant SPF 30 or higher on uncovered skin. Reapply sunscreen as directed and avoid indoor tanning.24

In the randomized Nambour trial, daily sunscreen reduced the number of cSCC tumors over 4.5 years, with a rate ratio of 0.61 compared with discretionary use; the trial did not show a significant BCC reduction.18 Extended follow-up recorded 11 melanomas in the daily-use group and 22 in the discretionary-use group, but the total melanoma numbers were small.19

What this means for you: sunscreen is one proven layer, not permission to extend exposure and not a guarantee against every cancer.

Nicotinamide is a selected option, not a universal vitamin

In the ONTRAC randomized trial, 386 immunocompetent adults with at least two keratinocyte cancers in the previous five years received nicotinamide 500 mg twice daily or placebo for 12 months. New keratinocyte cancers were 23% lower during treatment, but benefit did not persist after the medicine stopped.20

A separate randomized trial in solid-organ transplant recipients did not show the same benefit.21 Nicotinamide does not replace ultraviolet protection, surveillance, or treatment. Discuss whether your history resembles the studied group and whether kidney or liver disease, pregnancy, medicines, or pill burden changes the choice. Nicotinamide is not the same as niacin.

Immune suppression changes risk

Organ-transplant recipients and other immunosuppressed patients can develop more frequent and more aggressive cSCC. A high-burden plan may include closer surveillance, coordinated field treatment, selected systemic chemoprevention, and transplant-team review of immunosuppression.22

Never stop or change antirejection or immune-modifying medicine on your own. Dermatology and the transplant or prescribing team should make that decision together.

How can I build a one-page plan?

Build a One-Page Follow-Up Plan

Before leaving the treatment phase, fill in:

Build a One-Page Follow-Up Plan
Plan itemWrite down the answer
Exact cancer and riskDiagnosis, stage or risk group, and key pathology features
Treatment and clearanceWhat was done and how margins or response were assessed
Next visitDate, clinician, and why that interval was chosen
What the visit includesTreated site, full skin, lymph nodes, imaging, oncology, treatment effects
What should not waitSpecific skin, scar, node, neurologic, or systemic changes
Prevention planShade, clothing, sunscreen, no tanning, and any selected medication discussion
Who owns the planDermatologist, Mohs surgeon, oncologist, surgeon, transplant team, or shared care

If your instructions say only “follow up as needed,” ask for the time frame and the clinician responsible.

What does the follow-up evidence say?

Evidence by the Numbers

Evidence by the NumbersMost observed cSCC recurrences appeared early

Most observed cSCC recurrences appeared early

96% within 2 years

Population
Four-center retrospective study with five-year outcomes for 598 surgically excised cutaneous squamous cell carcinomas
Outcome
Timing of 40 local recurrences or lymph-node metastases
Time horizon
Five-year follow-up; timing concentrated in the first two years

What it means: The first two years deserve a defined follow-up plan, especially when the original cSCC was high risk.

Limitations: Retrospective surgical cohort; it does not define the recurrence probability or ideal visit interval for every cSCC.

References: 7

Evidence by the NumbersRepeated keratinocyte cancers predict more new tumors

Repeated keratinocyte cancers predict more new tumors

40.7% vs 82.0%

Population
Prospective cohort excluding immunocompromised patients
Outcome
Five-year probability of another basal or squamous cell carcinoma after a first lifetime tumor versus after a nonfirst tumor
Time horizon
Five years

What it means: One tumor justifies surveillance; a pattern of repeated tumors makes a deliberate prevention and follow-up plan even more important.

Limitations: University and Veterans Affairs cohort; the percentages are not an individual forecast.

References: 9

Evidence by the NumbersA second melanoma can appear years later

A second melanoma can appear years later

3.9% at 5 years; 6.7% at 10 years

Population
Population-based cohort of 152,811 people treated surgically for a first nonmetastatic cutaneous melanoma
Outcome
Cumulative incidence of a second primary melanoma
Time horizon
Five and ten years

What it means: Recurrence-focused follow-up may become less frequent, but lifelong skin surveillance still matters.

Limitations: Registry-based estimates; risk varies with age, phenotype, family history, and surveillance intensity.

References: 10

Evidence by the NumbersHigh-risk facial BCC can recur late

High-risk facial BCC can recur late

56% after year 5

Population
Randomized trial with ten-year follow-up of high-risk primary facial basal cell carcinomas treated with Mohs surgery or standard excision
Outcome
Proportion of observed primary-tumor recurrences occurring more than five years after treatment
Time horizon
Ten years

What it means: A clean first few years are reassuring, but they do not make long-term skin surveillance irrelevant after high-risk BCC.

Limitations: High-risk facial BCC trial; this timing should not be transferred to every low-risk BCC.

References: 11

Evidence by the NumbersDaily sunscreen reduced cSCC burden

Daily sunscreen reduced cSCC burden

Rate ratio 0.61

Population
Randomized Nambour trial in Australian adults
Outcome
Number of cutaneous squamous cell carcinoma tumors with daily versus discretionary sunscreen
Time horizon
4.5 years

What it means: Regular sunscreen is one proven prevention layer, best combined with shade, clothing, and avoidance of indoor tanning.

Limitations: The trial used SPF 15-plus on specified sites and did not show a significant BCC reduction.

References: 18, 19

Evidence by the NumbersNicotinamide helped one narrowly defined high-risk group

Nicotinamide helped one narrowly defined high-risk group

23% fewer during treatment

Population
Randomized trial of 386 immunocompetent adults with at least two keratinocyte cancers in the previous five years
Outcome
New keratinocyte cancers with nicotinamide 500 mg twice daily versus placebo
Time horizon
Twelve months of treatment

What it means: Nicotinamide can be discussed for selected high-risk patients; it is not a substitute for surveillance or ultraviolet protection.

Limitations: Benefit did not persist after treatment stopped, and a transplant-recipient trial did not show the same benefit.

References: 20, 21

Frequently asked questions about follow-up

Frequently Asked Questions

Which schedule should I follow if two clinicians give different intervals?

Ask which diagnosis, stage, or risk factor drives each recommendation. Often one clinician is watching the skin while another is watching for regional or distant disease. The plan should say who owns each task and when the next visit occurs.

Am I cured after treatment?

Many skin cancers are cured with appropriate treatment. “Cured” does not mean zero chance of recurrence or a new primary. Your pathology, treatment, and time since treatment determine how reassuring a clean examination is.

Do I need routine scans after BCC?

Usually not. Imaging is reserved for a specific concern or selected locally advanced or metastatic disease.

Do I need routine scans after cSCC?

Most low-risk cSCC survivors do not. Imaging may fit regional disease, clinically significant nerve involvement, very-high-risk tumors, symptoms, or an abnormal examination.

Do I need routine scans after melanoma?

Not for asymptomatic stage IA–IIA melanoma. Selected stage IIB–IV patients with no evidence of disease may receive imaging for a defined period, usually concentrated within the first five years.5,6

Is a new spot a recurrence?

A new spot elsewhere is often a new lesion, not spread from the old cancer. It still deserves assessment when it is changing, symptomatic, bleeding, or not healing.

How often should I examine my own skin?

A monthly routine is practical for many survivors, especially when a partner helps with the scalp and back. The most important action is not the exact date; it is reporting a meaningful change instead of waiting for the next office visit.

Should I have blood tests for skin cancer?

There is no routine blood test that replaces examination after BCC, cSCC, or early melanoma. Blood work may be used for systemic-treatment monitoring or a specific higher-stage question.

Does SPF 100 let me stay outside twice as long as SPF 50?

No. Shade, clothing, adequate application, and reapplication still matter. Sunscreen should not be used to extend exposure.

Should everyone who has had a skin cancer take nicotinamide?

No. The strongest randomized benefit was shown during treatment in immunocompetent adults with at least two keratinocyte cancers in five years.20 It did not show the same result in transplant recipients.21

When should genetic counseling be discussed?

Most skin-cancer survivors do not need genetic testing. It becomes more relevant with several primary melanomas, melanoma plus pancreatic cancer or astrocytoma in the family, very young onset, unusual tumor combinations, or a sebaceous carcinoma pattern concerning for Lynch syndrome.17,25

Who reviewed and authored this follow-up guide?
Portrait of Dr. Thomas L.H. Hocker

About the Author

Dr. Thomas L.H. Hocker is a Harvard- and Mayo Clinic-trained, triple board-certified dermatologist, Mohs surgeon, and dermatopathologist. He is the Founding Director of Dermatologic Surgery at the UMKC School of Medicine and University Health and an Iron Surgeon lecturer at the American Society for Dermatologic Surgery. His work focuses on Mohs surgery for melanoma, complex and rare skin tumors, and aesthetic reconstruction after skin-cancer treatment. He co-authored the best-selling textbook Review of Dermatology and created Skin Trust to give patients and clinicians free access to clear, current, evidence-based education.

Read Dr. Hocker's background and mission

Dr. Hocker earned his bachelor's degree with honors from Yale University, where he was inducted into Phi Beta Kappa. As a Winston Churchill Scholar, he then studied at the University of Cambridge and earned an M.Phil. in Organic Chemistry. He received his M.D. with honors from Harvard Medical School, where his research focused on melanoma genetics. He completed dermatology residency at Mayo Clinic, a dermatopathology fellowship at the University of Michigan, and a Mohs micrographic and reconstructive surgery fellowship at Mayo Clinic. He is board-certified in Dermatology, Dermatopathology, and Mohs Micrographic Surgery.

Dr. Hocker serves as the Founding Director of Dermatologic Surgery at the UMKC School of Medicine and University Health. He is an internationally invited lecturer and speaker who teaches about Mohs surgery for melanoma, complex and rare tumors, dermatopathology, and aesthetic reconstruction after skin-cancer treatment. He has also been selected as an Iron Surgeon lecturer by the American Society for Dermatologic Surgery. He is the co-author of Review of Dermatology, a best-selling dermatology review textbook, and he continues to teach and mentor medical students, residents, and physicians.

Skin Trust exists because Dr. Hocker believes access to excellent medical knowledge should not depend on geography, wealth, or proximity to a major academic center. After training at several of the world's leading institutions, he sees that education as both a gift and a responsibility: to translate current evidence, expert judgment, and hard-won clinical experience into guidance that patients, families, and clinicians can actually use.

The mission is to increase awareness, reduce avoidable suffering, and give every person equal access to trustworthy, up-to-date information that can help them make the best decisions for their life. Skin Trust also extends Dr. Hocker's lifelong commitment to teaching, writing, and mentoring medical students and residents as they build lives and careers of purpose and service.

For Dr. Hocker, this work is also an expression of faith. He regards the opportunities to learn at Yale, Cambridge, Harvard, Mayo Clinic, and the University of Michigan as blessings from God. Teaching, writing, mentoring, and building Skin Trust are ways to pay those blessings forward in service to patients, learners, and the broader community. His faith is the personal motivation to do this work carefully, generously, and with integrity; it is not a condition of using or benefiting from this free resource.

View Review of Dermatology Read Dr. Hocker's full biography
References for this follow-up guide

References

  1. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Basal Cell Skin Cancer. Version 2.2026.
  2. Kim JYS, Kozlow JH, Mittal B, Moyer J, Olenecki T, Rodgers P. Guidelines of care for the management of basal cell carcinoma. J Am Acad Dermatol. 2018;78(3):540-559. PMID: 29331385. DOI: 10.1016/j.jaad.2017.10.006.
  3. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Squamous Cell Skin Cancer. Version 2.2026.
  4. Kim JYS, Kozlow JH, Mittal B, et al. Guidelines of care for the management of cutaneous squamous cell carcinoma. J Am Acad Dermatol. 2018;78(3):560-578. PMID: 29331386. DOI: 10.1016/j.jaad.2017.10.007.
  5. National Comprehensive Cancer Network. NCCN Clinical Practice Guidelines in Oncology: Melanoma: Cutaneous. Version 2.2026.
  6. Swetter SM, Tsao H, Bichakjian CK, et al. Guidelines of care for the management of primary cutaneous melanoma. J Am Acad Dermatol. 2019;80(1):208-250. PMID: 30392755. DOI: 10.1016/j.jaad.2018.08.055.
  7. Khan K, Mykula R, Kerstein R, et al. A 5-year follow-up study of 633 cutaneous SCC excisions: rates of local recurrence and lymph node metastasis. J Plast Reconstr Aesthet Surg. 2018;71(8):1153-1158. PMID: 29803777. DOI: 10.1016/j.bjps.2018.03.019.
  8. Helvind NM, Weitemeyer MBM, Chakera AH, et al. Stage-specific risk of recurrence and death from melanoma in Denmark, 2008-2021: a national observational cohort study of 25,720 patients with stage IA to IV melanoma. JAMA Dermatol. 2023;159(11):1213-1222. PMID: 37650576. DOI: 10.1001/jamadermatol.2023.3256.
  9. Wehner MR, Linos E, Parvataneni R, et al. Timing of subsequent new tumors in patients who present with basal cell carcinoma or cutaneous squamous cell carcinoma. JAMA Dermatol. 2015;151(4):382-388. PMID: 25588079. DOI: 10.1001/jamadermatol.2014.3307.
  10. Wiener AA, Schumacher JR, Racz JM, et al. Incidence of second primary melanoma in cutaneous melanoma survivors. Ann Surg Oncol. 2022;29(8):5125-5132. PMID: 35505144. DOI: 10.1245/s10434-022-11725-8.
  11. van Loo E, Mosterd K, Krekels GAM, et al. Surgical excision versus Mohs micrographic surgery for basal cell carcinoma of the face: a randomized clinical trial with 10-year follow-up. Eur J Cancer. 2014;50(17):3011-3020. PMID: 25262378. DOI: 10.1016/j.ejca.2014.08.018.
  12. Helbig D, Ziemer M, Dippel E, et al. S1-guideline atypical fibroxanthoma and pleomorphic dermal sarcoma. J Dtsch Dermatol Ges. 2022;20(2):235-243. PMID: 35099104. DOI: 10.1111/ddg.14700.
  13. Ørholt M, Aaberg FL, Abebe K, et al. Risk factors for local atypical fibroxanthoma recurrence and progression to pleomorphic dermal sarcoma: a meta-analysis of individualized participant data. J Surg Oncol. 2022;126(3):555-562. PMID: 35441377. DOI: 10.1002/jso.26898.
  14. Saiag P, Lebbe C, Brochez L, et al. Diagnosis and treatment of dermatofibrosarcoma protuberans: European interdisciplinary guideline—update 2024. Eur J Cancer. 2025;218:115265. PMID: 39904126. DOI: 10.1016/j.ejca.2025.115265.
  15. Kibbi N, Owen JL, Worley B, et al. Evidence-based clinical practice guidelines for extramammary Paget disease. JAMA Oncol. 2022;8(4):618-628. PMID: 35050310. DOI: 10.1001/jamaoncol.2021.7148.
  16. Worley B, Owen JL, Barker CA, et al. Evidence-based clinical practice guidelines for microcystic adnexal carcinoma: informed by a systematic review. JAMA Dermatol. 2019;155(9):1059-1068. PMID: 31268498. DOI: 10.1001/jamadermatol.2019.1251.
  17. Utikal J, Nagel P, Müller V, et al. S1-guideline sebaceous carcinoma. J Dtsch Dermatol Ges. 2024;22(5):730-747. PMID: 38679790. DOI: 10.1111/ddg.15405.
  18. Green A, Williams G, Neale R, et al. Daily sunscreen application and beta-carotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomized controlled trial. Lancet. 1999;354(9180):723-729. PMID: 10475183. DOI: 10.1016/S0140-6736(98)12168-2.
  19. Green AC, Williams GM, Logan V, Strutton GM. Reduced melanoma after regular sunscreen use: randomized trial follow-up. J Clin Oncol. 2011;29(3):257-263. PMID: 21135266. DOI: 10.1200/JCO.2010.28.7078.
  20. Chen AC, Martin AJ, Choy B, et al. A phase 3 randomized trial of nicotinamide for skin-cancer chemoprevention. N Engl J Med. 2015;373(17):1618-1626. PMID: 26488693. DOI: 10.1056/NEJMoa1506197.
  21. Allen NC, Martin AJ, Snaidr VA, et al. Nicotinamide for skin-cancer chemoprevention in transplant recipients. N Engl J Med. 2023;388(9):804-812. PMID: 36856616. DOI: 10.1056/NEJMoa2203086.
  22. Massey PR, Schmults CD, Li SJ, et al. Consensus-based recommendations on prevention of squamous cell carcinoma in solid-organ transplant recipients. JAMA Dermatol. 2021;157(10):1219-1226. PMID: 34468690. DOI: 10.1001/jamadermatol.2021.3180.
  23. American Society for Dermatologic Surgery. What Is a Skin Cancer Screening? Accessed July 23, 2026.
  24. American Academy of Dermatology. How to Prevent Skin Cancer. Accessed July 23, 2026.
  25. National Cancer Institute. Genetics of Skin Cancer (PDQ), Health Professional Version. Updated 2025.