Could the small bump underneath my Mohs incision line (surgery performed 2 months ago) be a basal cell recurrence? (Phtoo)

Moh’s surgery on the face often requires surgical repair and reconstruction to reapproximate the skin edges. Flaps or direct closure techniques are used. It is important that you optimize scar healing during this phase in order to reduce longterm scars. For red scars, we use Vbeam laser, followed by fractional laser for scar topography and contour. We recommend Plato’s Scar Serum twice daily for the immediate postoperative period. Fractional laser is safe for scar laser therapy.
There are treatments for swelling and edema of the scars. If there is residual sutures or edema, we advise you to follow a scar treatment protocol that can minimize the time to recovery. Our office specializes in scar revisions for Moh’s surgery.
Best,
Dr. Karamanoukian
Realself100 Surgeon

Thankfully the cure rate for Mohs surgery is extremely high for most skin cancers, >99% for basal cell skin cancer.  The likelihood of a recurrence is very low.  The timeline for a recurrence can vary significantly, but when they recur, they usually continue to grow.  The most common causes of post-operative bumps are usually benign, and typically start improving.  Some common causes are:
1. Dissolving sutures - Sutures that have not completely dissolved can often be felt below the surface.  Sometimes they will try to work their way to the surface before they dissolve completely, "spitting."   Sometimes they can also fester a little, causing a small pimple, sometimes even draining a little pus.  Sometimes your doctor may recommend making a tiny knick or incision overtop to express and remove the remaining stitch material.
2. Scar - Sometimes nodules of scar tissue can develop.  Sometimes this occurs around the deep stitches.  These often soften overtime as the scar "matures."  Occasionally people develop abnormally thick scars called "hypertrophic scars (HTS)" or "keloid scars."  These thicker scars tend to occur more often in people with darker skin types.  Sometimes these thicker scars benefits from early intervention with treatments like steroid injections into the scar or application of a silicone dressing.
3. Cysts - The greasy ointment, dressing covers, swelling and stitching can compress and block oil glands, leading to blackheads, cysts, and pimples along a scar, particularly during the first couple of months.  As things settle down, these become less common.  Good skin care and warm compresses can help open up pores as well.
Although most post-operative bumps are benign, the best advice is to see your Mohs surgeon soon to have the bump evaluated.  Most well-trained Mohs surgeons can easily tell what the bump is, and hopefully give you some peace of mind!

There are several possibilities regarding the bump in the middle of your scar following Mohs surgery. It could very well represent deep recurrence of the BCC but, because of the nature of Mohs surgery, it is somewhat unlikely, particularly if your Mohs surgeon was fellowship-trained. Another possibility would be a reaction to deep absorbable suture in that location if such suture was used. Not all absorbablesutures are absorbed as they should and can sometimes cause a foreign body reaction which would manifest itself as a deep bump. This type of reaction would then culminate in any remaining suture material "spitting" through to the surface of the wound. You should ask your Mohs surgeon to evaluate the wound for you.