• Creams, light and cold for basal cell carcinoma: For a thin basal cell carcinoma there are four treatments that avoid an operation: two creams, a light treatment and freezing.
• Cancer stem cell theory and phenotypic plasticity: The idea that a tumour is organised like a tissue, with a small pool of stem-like cells that renew it and a bulk that cannot, so killing the bulk shrinks the tumour but the stem-like cells regrow it.
• Why people stop taking hedgehog inhibitors: The pills that shrink advanced basal cell carcinoma cause muscle cramps, loss of taste, hair loss and weight loss in almost everyone who takes them.
• Curettage and cautery: Scraping a small, low-risk skin cancer away with a spoon-shaped blade under local anaesthetic and then sealing the surface with heat, usually repeated two or three times in the same sitting.
• The next skin cancer: second primaries after a keratinocyte cancer: The likeliest thing to happen after a basal cell or squamous cell carcinoma is not that this one comes back.
• The growth pattern on a basal cell carcinoma report: nodular, superficial, infiltrative, basosquamous: Basal cell carcinomas are sorted by the shape they grow in, and the shape decides how much skin has to be taken and who does it.
• Sun protection after a skin cancer diagnosis: Not a lecture but a short list: shade between 11am and 3pm, clothes and a wide-brimmed hat, SPF 30 or more with four or five UVA stars used generously and reapplied, never a sunbed, and a vitamin D supplement in winter because the rest of the list reduces it.
• Skin grafts and flaps after skin cancer surgery: Two ways of closing a hole in the skin that is too big to stitch.
• The scar on the face after skin cancer surgery: Every skin cancer operation leaves a scar, and on a face it is the part people mind most.
• The margin in skin cancer surgery: When a skin cancer is cut out, the surgeon takes a rim of normal-looking skin around it, because the cancer reaches further than the eye can see.

Biomarker results to ask for: Histologic subtype and high-risk location (H-zone of face), PTCH1 / SMO / SUFU alterations (research; SMO mutations predict hedgehog-inhibitor resistance), Perineural invasion, Germline PTCH1 (Gorlin), Growth pattern, low or high risk, which is the single most consequential line on the report (RCPath G123), Squamous differentiation, reported when moderate or severe, because basosquamous tumours recur and metastasise more often, Level of invasion and thickness: beyond subcutaneous fat, or more than 6 mm, are high-risk features and upstage to pT3, Perineural invasion, which is collected for nodular but not for superficial tumours because superficial tumours cannot show it, Margins: involved at 0 mm, or clear but under 1 mm, both count as high risk, PTCH1, SMO and SUFU alterations, which are the biology rather than a routine test; germline PTCH1 or SUFU indicates Gorlin syndrome.

Scans and tests linked to this cancer: Multidisciplinary tumour boards, Confocal microscopy and optical coherence tomography for skin (VivaScope, VivoSight, deepLive), Dermoscopy, total-body photography & AI skin analysis, Skin cancer screening (visual skin examination).

Bring copies of scan reports, pathology and blood results, and a list of every medicine and supplement.

• Choosing between surgery, curettage, freezing, a cream and photodynamic therapy: For a superficial or low-risk nodular basal cell carcinoma this is a real choice and not a formality, so here are the numbers instead of the phrase several options are available. Surgery has the highest cure rate: the Cochrane review of 52 randomised trials and 6,690 participants concluded that surgical interventions have the lowest recurrence rates. In the UK SINS trial, 501 people with primary nodular or superficial disease at low-risk sites were randomised between imiquimod cream (once daily, six weeks for superficial and twelve for nodular) and excision with a 4 mm margin: treatment succeeded in 83.6 percent against 98.4 percent at three years and 82.5 percent against 97.7 percent at five, and most cream failures happened in the first year. Among the non-surgical options, a Dutch trial of 601 people with superficial disease gives the ranking at five years: imiquimod 80.5 percent tumour-free, fluorouracil cream 70.0 percent, photodynamic therapy 62.7 percent. Curettage and cautery, scraping the lesion away and sealing the surface with heat, usually repeated two or three times in one sitting, is a surgical option for low-risk disease; the BAD notes that unlike an excision it leaves no margins for a pathologist to check but is generally considered effective for a low-risk basal cell carcinoma. Cryotherapy is offered for superficial lesions and the BAD says it generates a wound that usually heals with a scar. Now the other side, because cure rate is not the only axis. Creams take weeks of a visibly inflamed, itching, weeping face (in SINS, itching in 211 of the imiquimod group against 129 of the surgery group); photodynamic therapy causes moderate to severe pain and burning during the treatment itself; and the cosmetic result of the non-surgical options is better, not worse. The Cochrane review found observers rated the outcome good or excellent in 60.6 percent after imiquimod against 35.6 percent after excision, and after photodynamic therapy against excision 87.1 percent against 46.6 percent, while patients rated imiquimod and surgery the same. So: surgery is one appointment and the highest cure rate and a scar; a cream is six to twelve weeks of a sore face, a one-in-six chance of failure, and usually a better-looking result. Both are defensible. Not treating at all is a third option the BAD names for a slow-growing lesion on a non-critical site or where someone could not tolerate treatment. (Wide local excision, Curettage and cautery, Mohs surgery, Imiquimod, Fluorouracil (5-FU), Methyl aminolevulinate, Aminolevulinic acid (topical, for photodynamic therapy), Cryoablation, Photodynamic therapy lasers and light sources, Curative intent vs palliative intent, Multidisciplinary tumour boards)
• High-risk or recurrent: Mohs micrographic surgery or excision with complete margin assessment; radiotherapy if surgery not feasible. (IMRT / IGRT (modern external beam))
• Locally advanced or metastatic: Vismodegib or sonidegib; cemiplimab after hedgehog-inhibitor failure or intolerance; multidisciplinary review for surgery/radiotherapy after response. (Vismodegib, Sonidegib, Cemiplimab)
• Low-risk: Standard excision with 4 mm margin, curettage and electrodesiccation, or topical imiquimod / 5-FU / photodynamic therapy for superficial lesions. (Fluorouracil (5-FU))
• Will it come back, and will I get another one: Two different questions get muddled here and they have different answers. Will this one come back: usually not, and the risk depends on what it was and how it was treated. In the Dutch randomised trial of high-risk facial basal cell carcinoma, ten-year recurrence was 4.4 percent after Mohs and 12.2 percent after standard excision for primary tumours, and 3.9 against 13.5 percent for recurrent ones; the same trial found that 56 percent of the recurrences of primary tumours appeared more than five years after treatment, which is why a clear five years is reassuring but is not the end of the story for a high-risk lesion on the face. Will I get another one: probably, and sooner than you would guess. In a meta-analysis of 17 studies, the three-year cumulative risk of a further basal cell carcinoma after a first was 44 percent, at least ten times the rate of first tumours in a comparable population, while the risk of a squamous cell carcinoma after a basal cell carcinoma was 6 percent. Those are cohort figures rather than a prediction for you, and they are about new cancers on damaged skin rather than this one returning. What follow-up is offered follows from that, and it is lighter than most people expect. The BAD says not everyone needs it, that people are usually discharged if the recurrence risk is low and they are not at high risk of future skin cancers, and that it is considered for advanced disease, a high risk of recurrence, or a high risk of multiple cancers such as people with weakened immune systems or genetic syndromes. Cancer Research UK says an early basal cell carcinoma may mean a single follow-up appointment and then none. Being discharged is not being dropped: it is a transfer of the surveillance to you, and both the BAD and Cancer Research UK are explicit about what you are then meant to do. The BAD puts a frequency on it, once a month, with someone else looking at the places you cannot see; Cancer Research UK asks you to know what your skin normally looks like and does not name an interval. Both say to go to the GP for any mark that is growing, changing, bleeding or not healing, including a change where this one was treated. (The next skin cancer: second primaries after a keratinocyte cancer, Sun protection after a skin cancer diagnosis, Mohs surgery, Wide local excision, Survivorship care and late-effects surveillance, Late effects and survivorship toxicity, Field cancerisation)
• Choosing between an operation and a cream for a superficial tumour: This is a real choice and the numbers for it exist. In 601 Dutch patients with superficial basal cell carcinoma, five-year tumour-free survival was 80.5 per cent with imiquimod cream, 70.0 per cent with fluorouracil cream and 62.7 per cent with methyl aminolevulinate photodynamic therapy; imiquimod beat photodynamic therapy with a hazard ratio for failure of 0.48 and fluorouracil with 0.65. Against surgery all of them lose: SINS randomised 501 people in the United Kingdom and found clinical success at five years of 82.5 per cent with imiquimod against 97.7 per cent with excision, a relative risk of 0.84 whose confidence interval fell below the non-inferiority margin, so imiquimod is inferior rather than unproven. Cryotherapy matched photodynamic therapy on five-year recurrence, 20 against 22 per cent, and lost badly on appearance, 16 against 60 per cent excellent. Failures come early in every one of these trials, so a lesion still clear at a year is likely to stay clear. (Creams, light and cold for basal cell carcinoma, Photodynamic therapy against imiquimod against fluorouracil for superficial basal cell carcinoma, SINS (surgical excision against imiquimod cream for basal cell carcinoma), Photodynamic therapy against cryotherapy for superficial basal cell carcinoma, Imiquimod, Fluorouracil (5-FU))
• The same choice for a nodular tumour, where it goes worse: The creams and the light are licensed for the thin superficial form, and stretching them to the thicker nodular form has been tested twice with the same answer. Methyl aminolevulinate photodynamic therapy against excision gave five-year recurrence of 14 against 4 per cent and a sustained complete response of 76 against 96 per cent, with an excellent or good cosmetic outcome in 87 against 54 per cent. Scraping the tumour off first and then applying imiquimod, tested in the SCIN trial, gave freedom from treatment failure at five years of 77.8 against 98.2 per cent, a relative risk of failure of 15.93. Both are defensible for someone who cannot or will not have facial surgery, and neither is equivalent to it. (Photodynamic therapy against surgery for nodular basal cell carcinoma, SCIN (curettage then imiquimod against excision for nodular basal cell carcinoma), Creams, light and cold for basal cell carcinoma, Curettage and cautery)
• Shrinking a tumour before the operation: For a large facial basal cell carcinoma where the operation would cost an eyelid or a nostril, a hedgehog inhibitor can be given first. VISMONEO gave vismodegib for a mean of 6.0 months to 55 patients with a mean lesion size of 47.3 mm and downstaged the planned surgery in 44 of them (80 per cent, 67 to 90), with 27 complete responses of which 25 were proved on biopsy. The part usually left out belongs in the conversation: at three years 16 of those 44 patients had a known recurrence, 36 per cent. The drug changes the operation, it does not replace it. (VISMONEO (vismodegib before surgery for locally advanced basal cell carcinoma), Vismodegib, Why people stop taking hedgehog inhibitors, Mohs surgery)
• Living with a hedgehog inhibitor: Vismodegib and sonidegib work and most people stop taking them. STEVIE gave vismodegib to 1,215 patients in ordinary practice: response was 68.5 per cent in locally advanced disease, 98 per cent had a treatment-emergent adverse event, 23.8 per cent had a serious one, and the median treatment duration was 8.6 months, with only 12 per cent still taking it at the analysis. The characteristic events are muscle spasms, loss of taste, hair loss and weight loss, none dangerous and all wearing. Most of them resolve within a year of stopping. Intermittent dosing, neoadjuvant courses and topical delivery are the three attempts to get round it. (STEVIE (vismodegib in ordinary practice), Why people stop taking hedgehog inhibitors, Vismodegib, Sonidegib, Hedgehog pathway inhibitors)
• After a hedgehog inhibitor has failed or cannot be tolerated: Cemiplimab, a PD-1 antibody. In 84 patients with locally advanced disease who had progressed on, could not tolerate, or had no better than stable disease after nine months of a hedgehog inhibitor, objective response by independent central review was 31 per cent (21 to 42) with five complete responses; grade 3 or 4 treatment-emergent adverse events occurred in 48 per cent and serious events in 35 per cent. It was approved in February 2021 on that single-arm evidence and there is no randomised comparison. That basal cell carcinoma responds to checkpoint blockade at all is not obvious for a tumour that almost never spreads, and is explained by its very high ultraviolet mutational burden. (Cemiplimab in basal cell carcinoma after a hedgehog inhibitor, Cemiplimab, Immune checkpoint inhibitors, Tumour mutational burden (TMB), Immune-related adverse events (irAEs))
• What is available in England: Less than the approvals suggest. NICE technology appraisal TA489 recommendation 1.1 does not recommend vismodegib within its marketing authorisation for metastatic basal cell carcinoma or for locally advanced disease unsuitable for surgery or radiotherapy: the committee found the comparison with best supportive care not good enough for decision-making and the cost per quality-adjusted life year much higher than 30,000 pounds. Recommendation 1.2 allows anyone already on it to continue. There is no NICE appraisal of sonidegib, and none of cemiplimab in basal cell carcinoma. The commonest cancer in human beings has one NICE technology appraisal and it is a refusal. (Vismodegib, Sonidegib, Cemiplimab, Why people stop taking hedgehog inhibitors)

From the standard of care recorded for this cancer; which apply depends on your stage and biomarkers. Ask which the team recommends and why.