Field Notes · July 27, 2026 · 8 min · By Fletcher Imafidon
The wait between biopsy and Mohs: how long is too long
A biopsy comes back positive and the surgery date is nine weeks away. Published growth data on nonmelanoma skin cancer says most of that wait costs little, and it also says exactly which tumors and which changes should send you back to the phone.
The pathology result arrives, the diagnosis is confirmed, and the next available Mohs appointment is in nine weeks. Almost nobody is told how to feel about that number. The word cancer has entered the conversation and the scheduling department has responded with a date two months out, and those two facts sit badly together for anyone left to reconcile them alone.
The reconciliation is available, and it is more specific than reassurance. There is published data on how fast these tumors actually grow while people wait, because health systems with long queues have measured it.
The original element in this piece is a wait time triage: a way to place your own delay against what the growth literature reports, combined with a dated change log you keep during the wait and three named triggers that convert a reasonable wait into a phone call. Patient material on skin cancer explains what the diagnosis means and what the surgery involves. It does not tell you how to spend the interval, and the interval is where the anxiety lives.
What the growth data says. Work following nonmelanoma skin cancers through periods of delayed treatment and continued growth has reported that these tumors do enlarge while untreated, and that the rate is generally modest over the timescales involved in ordinary scheduling. A separate series looking specifically at the growth of periocular basal cell carcinomas put numbers on that in one of the most consequential locations on the body, since a millimeter near an eyelid margin costs far more reconstructively than a millimeter on a shoulder. The general position taken by cancer information services including the National Cancer Institute reflects the same underlying reality: basal cell carcinomas are typically slow growing and rarely metastasize, and squamous cell carcinomas are a more heterogeneous group where subtype and site drive the urgency.
The practical translation is that a wait measured in a small number of weeks is, for a typical low risk basal cell carcinoma on the trunk or limb, unlikely to change what surgery is required. The same wait for a rapidly enlarging squamous cell carcinoma on the ear, or for any tumor sitting on an eyelid margin or nostril rim, is a different proposition, because the constraint there is not survival but how much functional tissue lies between the tumor and the structure next to it.
Three variables that set your own urgency. The first is what the biopsy actually said, which is why it is worth reading your report properly rather than stopping at the diagnosis line. Basal cell versus squamous cell matters. So does the subtype descriptor, since infiltrative, morpheaform and micronodular patterns behave differently from nodular ones, and so does any mention of perineural involvement or poor differentiation. The second is location, and specifically whether the tumor sits within a few millimeters of a free margin, meaning an eyelid edge, a nostril rim, a lip border or the ear. The third is trajectory, meaning what the lesion has visibly done over the previous two months, which only you can report.
The change log. Once a week, on the same day, photograph the site in the same light with a ruler in frame, and write one line: any bleeding this week, any new crusting, any increase in size you can see against the ruler, any new numbness or tingling in the surrounding skin, any pain. That last pair matters more than its prominence in patient literature suggests. New numbness, tingling or persistent pain in the skin around a skin cancer is one of the few symptoms that can signal nerve involvement, and it changes the risk category of the tumor rather than just its size.
Trigger one, visible growth against the ruler. Not a feeling that it looks bigger. A measurable increase across two consecutive weekly photographs taken with the scale in frame. That is a call, and it is a call with evidence attached.
Trigger two, new nerve symptoms. New numbness, tingling, twitching or a persistent ache in the skin around the lesion, at any point during the wait, is a same week call rather than something to mention at the eventual appointment.
Trigger three, repeated bleeding or a wound that will not close. A lesion that bleeds with minimal contact, or that has opened and stayed open for more than two weeks, has changed behavior, and behavior change during a wait is the thing worth reporting.
How to make the call count. When you ring, do not ask whether the wait is too long, because the person answering cannot evaluate that from a general question. Say the diagnosis and subtype from the report, say the site, say what changed and on which dates, and ask whether the change warrants review of the scheduled date. That is a question a triage nurse can act on. It is also, in most systems, the only mechanism by which a date actually moves, since queues are ordered by risk information and yours is the newest risk information available.
What is genuinely reassuring, and where it stops. For most people reading this, the answer will be that the wait is fine, that the tumor will be slightly larger and the surgery will be substantially the same, and that the anxiety is out of proportion to the biology. The place that reassurance stops is the free margin. Tumors adjacent to an eyelid, a nostril or a lip are not more dangerous to your life, but they are the ones where a few extra millimeters of spread converts a straightforward closure into a considerably more involved reconstruction, and where the case for pressing on scheduling is strongest. The same logic sits behind why certain sites and certain tumors get routed to Mohs in the first place.
What the studies do not tell you. The growth literature is observational, drawn from patients whose treatment happened to be delayed rather than from anyone assigned to wait, which means the tumors in those series are not a random sample. Nobody has published, and nobody will publish, a trial randomizing people to nine weeks versus two. There is also no established threshold in weeks at which harm begins, which is precisely why every conversation about this defaults to vague reassurance. The triage above substitutes something you can act on for a number that does not exist.
Use the wait rather than enduring it. One weekly photograph, one line of notes, and three specific things that would make you pick up the phone.