Mohs micrographic surgery is a specialized skin cancer removal technique that examines 100% of the surgical margin in real time — achieving cure rates up to 99% for primary basal cell carcinoma while sparing the maximum amount of healthy tissue. At Belaray Dermatology in Hicksville and Stony Brook, Long Island, three dual board-certified Mohs surgeons perform the procedure.
What Makes Mohs Surgery Different from Standard Excision?
In a standard excision, the surgeon removes the visible tumor plus a predetermined margin of surrounding tissue. The specimen is then sent to an offsite pathology lab, where a small sample (roughly 1–2% of the margin) is examined. Results return in 1–7 days, and if the margin is positive (cancer cells remain), a second surgery is scheduled.
Mohs surgery eliminates both of those limitations. The Mohs surgeon serves simultaneously as the surgeon and the pathologist. The tissue is processed in an on-site lab, sectioned horizontally (unlike the "bread-loaf" sectioning used in standard pathology), and examined under the microscope by the surgeon. This horizontal technique allows 100% of the peripheral and deep margins to be mapped and visualized before the patient leaves the surgical suite.
Who Is a Candidate for Mohs Surgery?
Mohs surgery is recommended — and is the standard of care — for skin cancers such as basal cell carcinoma and squamous cell carcinoma in the following situations:
- Location on the face, head, or neck — especially around the eyes, nose, ears, lips, and scalp, where tissue preservation is critical for function and cosmesis
- Recurrent tumors — cancers that have previously been treated and returned
- Aggressive histologic subtypes — morpheaform, infiltrative, or micronodular BCC; poorly differentiated SCC
- Large tumors or unclear borders — when the margin is difficult to define visually
- Immunocompromised patients — including organ transplant recipients or those on immunosuppressive therapy
- High-risk anatomic sites — hands, feet, genitals, pretibial leg
Not every skin cancer requires Mohs. Your dermatologist will determine the most appropriate treatment based on tumor type, location, size, and your medical history. Belaray's team performs standard excision, curettage and electrodesiccation, and topical therapy in addition to Mohs, and will recommend the treatment best suited to your specific case.
How Mohs Surgery Works: Step by Step
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Local anesthesia is administered
The treatment area is numbed with a local anesthetic injection. Most patients feel a brief sting; the area becomes fully numb within 60–90 seconds. You will be awake throughout the procedure but should feel no pain. For patients who feel anxious, Belaray offers Pro-Nox™ — patient-controlled nitrous oxide that you breathe on demand and that wears off within minutes, so you can still drive yourself home. Pro-Nox is available at our Hicksville office, and an additional fee applies.
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The visible tumor is removed (Stage 1)
The surgeon removes the clinically visible tumor plus a thin margin of surrounding tissue (approximately 1–2mm). The wound is dressed, and you will wait comfortably in the office while the tissue is processed.
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Tissue is mapped and processed in the on-site lab
The tissue is divided, color-coded, and precisely mapped — creating a diagram that records the exact location of each tissue section in relation to the wound. The tissue is then embedded in cutting compound, frozen, sectioned into thin horizontal slices, stained, and mounted on slides. This process takes approximately 1 to 2 hours per stage.
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The surgeon examines 100% of the margin
The Mohs surgeon examines every slide under the microscope. If cancer cells are present at any margin, their exact location is marked on the map. This allows the surgeon to precisely target only the area of positive margin in the next stage — removing no more healthy tissue than necessary.
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Additional stages are taken only where needed
If cancer remains, another thin layer is removed exclusively from the involved area and the process repeats. Approximately 80% of Mohs cases are cleared in one or two stages. Once the margins are clear — confirmed by the surgeon under the microscope — the procedure is complete.
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Reconstruction of the surgical wound
Once the tumor is fully removed, the wound is repaired. Depending on size and location, repair options include: allowing the wound to heal on its own (second intention), simple linear closure, a local skin flap, or a skin graft. For complex facial or periocular defects, Belaray's oculofacial plastic surgeon performs same-day oculoplastic reconstruction, available within the same practice at Belaray.
What to Expect After Mohs Surgery
Recovery timeline
Most patients resume normal activities within 24–48 hours. Strenuous activity and heavy lifting should be avoided for 1–2 weeks depending on location. Sutures are typically removed 7–14 days after the procedure. Redness, swelling, and bruising in the first 5–7 days are normal.
Scarring
Mohs surgery is designed to minimize scarring by preserving as much healthy tissue as possible. The appearance of the scar depends heavily on location, wound size, and the reconstruction technique used. Most scars fade significantly over 12–18 months. Belaray's cosmetic and laser services — including CO₂ fractional laser resurfacing and RF microneedling — are available for scar revision after healing is complete.
Follow-up and surveillance
A history of skin cancer increases your lifetime risk of developing additional skin cancers. Belaray recommends regular follow-up skin exams — typically every 6–12 months for the first 5 years after a Mohs procedure, then annually. Your provider will discuss a personalized surveillance schedule at your post-operative visit.
Key Things to Tell Your Mohs Surgeon
A few health conditions and medicines change how we plan your surgery. Please tell us about the following when you call, at your consultation, or on the day of your procedure, even if you think we already have it on file. When in doubt, mention it.
1. You have a weakened immune system
Tell us if you have had an organ transplant, are on chemotherapy, have HIV, or take medicine that suppresses your immune system (for example, for rheumatoid arthritis, lupus, inflammatory bowel disease, or after a transplant).
Why it matters: A weaker immune system can affect healing and the risk of infection, and some skin cancers behave more aggressively. Knowing helps us plan your treatment and follow-up.
2. You may need antibiotics before a procedure
Tell us if you have an artificial (prosthetic) heart valve, a heart transplant, certain heart conditions present from birth (congenital), or you have had an infection of a heart valve (infective endocarditis). Some joint replacements may also be relevant. These histories do not automatically mean you need antibiotics for clean skin surgery; your surgeon will assess the procedure and your individual risk.
Why it matters: These conditions can mean you need to take an antibiotic shortly before surgery to prevent a serious infection. We need to know ahead of time so it can be arranged.
3. You have a pacemaker or defibrillator
Tell us if you have a pacemaker, an implantable defibrillator (ICD), or any other implanted heart device.
Why it matters: During surgery we often use a tool that stops bleeding with a small electrical current (electrocautery). For patients with these devices, we adjust our technique to keep the device working safely.
This list is not complete. Always share your full medical history and a list of all your medicines and supplements, including any blood thinners.
The Three Mohs Surgeons at Belaray Dermatology
Belaray Dermatology has three dual board-certified Mohs surgeons (Dr. Jeffrey Ellis, Dr. Dana Baigrie, and Dr. Anthony Wong), each board-certified by the American Board of Dermatology in Dermatology and Micrographic Dermatologic Surgery.
Co-founder Dr. Jeffrey Ellis established Belaray's Mohs surgery program in 2006 and has performed thousands of Mohs procedures over his two-decade career at the practice.
From Patients Who Had Mohs Surgery at Belaray
“Highly recommend. As someone who is highly anxious the staff did an amazing job with comforting and distracting me for my Mohs surgery and I am grateful for them.”
“Had mohs surgery done on my arm. Fast and painless. Everyone in the office is friendly and professional. They made me very comfortable throughout the whole process.”
Frequently Asked Questions
How long does Mohs surgery take?
Most Mohs procedures take 2–4 hours from start to finish. Because each stage requires lab processing (roughly 1 to 2 hours per stage), patients should plan to spend most of the day at the office. Approximately 80% of cases are cleared in one or two stages.
Is Mohs surgery done under general anesthesia?
No. Mohs surgery is performed under local anesthesia in an outpatient surgical suite. Patients are awake and comfortable throughout. General anesthesia is not required and is rarely appropriate for this procedure.
What skin cancers is Mohs surgery used for?
Mohs surgery is the standard of care for basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), particularly on the face, ears, nose, lips, eyelids, scalp, hands, feet, and genitals. It is also used for certain cases of melanoma in situ and other rare skin tumors.
What is the cure rate for Mohs surgery?
Mohs surgery achieves a cure rate of up to 99% for primary basal cell carcinoma and up to 94–97% for recurrent tumors — higher than standard excision, radiation, or curettage and electrodesiccation.
What is the difference between Mohs surgery and a standard excision?
Mohs surgery checks 100% of the surgical margin under the microscope during the same visit, so the surgeon removes all of the cancer while sparing the most healthy tissue and confirms clear margins before you leave. A standard excision removes the tumor with a wider margin and sends it to an outside lab, with results in several days. Mohs has a higher cure rate and is preferred for the face and for recurrent or high-risk cancers.
Does Mohs surgery hurt?
Mohs surgery is not painful during the procedure. The area is numbed with local anesthesia, so you feel only the initial injection, and you stay awake and comfortable throughout. Belaray also offers Pro-Nox, patient-controlled nitrous oxide, for added comfort at its Hicksville office (an additional fee applies). Afterward, most patients manage any soreness with acetaminophen (Tylenol).
Will Mohs surgery leave a scar?
Any skin surgery leaves some scar, but because Mohs removes the smallest amount of tissue needed, it usually leaves the smallest possible scar. When reconstruction is appropriate, the wound is repaired the same day for the best cosmetic result, and scars keep fading over about 12 to 18 months. For cancers near the eye, Dr. Rachel Ellis performs oculofacial reconstruction after the Mohs surgeon clears the cancer.
Does Belaray perform same-day reconstruction after Mohs?
Yes. When reconstruction is appropriate, Belaray's surgical team repairs the wound the same day as tumor removal in most cases. For complex eyelid or periocular defects, a Belaray Mohs surgeon removes the cancer and Dr. Rachel Ellis, an oculofacial plastic and reconstructive surgeon, performs the reconstruction the same visit at the Hicksville office.
Ready to Schedule a Mohs Surgery Consultation?
Belaray Dermatology's three dual board-certified Mohs surgeons serve patients from Nassau and Suffolk counties at our Hicksville and Stony Brook offices. Most insurance plans accepted.