Delayed Margin Control Surgery
Offers one of the highest chances of cure of some skin cancers, particularly Basal Cell Carcinomas (BCCs) while ensuring the amount of skin removed is kept to a minimum.
In the 1930’s, Dr Frederick Mohs, from Wisconsin USA, first conceptualised and then developed his treatment for skin cancer. The technique has since come to be known as “Mohs Surgery” as due recognition for Dr Mohs’ outstanding contribution to the field of skin cancer treatment. Mohs surgery involves a specialist surgeon who cuts out the tumour and performs the histology (looking at the slides under a microscope) to ensure clearance.
Mohs Surgery has the highest rates of clearance for skin cancers but most importantly removes the most amount of tissue.
The problem with Mohs surgery in Australia is the cost, commonly amounting to thousands of dollars. There are also only a handful of Mohs surgeons nationally, only based in state capitals. Delayed Continuous margin controlled surgery was developed to give a similar clearance rates and similar tissue sparing benefits to ensure a cost effective way of giving you the smallest scar possible.
What is Continuous margin control Surgery?
Delayed Margin Control Surgery is a treatment for the total removal of skin cancers. The visible component of the cancer is surgically excised and marked at 6 and 12 O’Clock It is then sent to the lab for microscopic analysis under Formalin Fixed en face margin analyses, sometimes known as “slow mohs”. Any residual areas still positive for cancer are identified and subsequently removed. This process continues until all the cancer cells are cleared. Delayed Margin Control Surgery allows cancer cells to be fully and accurately tracked without guesswork until they are completely removed, removing the minimum amount of normal tissue.
Why is it important that all cancerous cells be removed?
If cancer cells are left behind at the time of initial surgery, there is a very high chance that the cancer will recur. When this happens it will frequently grow for a substantial period of time hidden under the previous surgical scar. This makes the subsequent treatment of the recurrent cancer much more extensive and difficult. Some skin cancers will also have the potential to metastasise. This is particularly important for squamous cell carcinomas were recurrent tumours metastasise 30% of the time.
When is Delayed margin control Surgery recommended?
Delayed Margin Control surgery is ideal when a skin cancer
- Is present in a difficult site, where the conservation of as much normal tissue is critical as on the face and especially around the nose, eyes, lips and ears.
- Has recurred after previous treatment(s).
- Has been incompletely excised after initial surgery.
- Is discovered to be certain microscopic type on initial biopsy.
What are the advantages of Continuous Margin Control Surgery?
- It ensures that all cancer cells are removed.
- As much healthy skin as possible is preserved.
- The cure rates are higher than with any other mode of treatment.
- Patient do not require general anaesthetic
- Clinic Based surgery is more cost effective than traditional Mohs surgery as a dermatopathologist or MOHS surgeon is not required to be present.
The Continuous Margin Control Surgery procedure:
The area to be treated is first numbed with local anaesthetic and the visible cancer is removed. A dressing is applied to the wound and the patient returns after 48 hrs.
The removed tissue is precisely oriented and then divided into small sections and the edges marked with coloured dye and a tissue map is drawn. The tissue is then handed to the laboratory technician.
Tissue processing and examination
The tissue is processed and cut by the technicians, then mounted on to microscope slides and stained using highly specialized chemicals to identify the different cell types. A doctor then examines the tissue under the microscope to see whether any residual cancer cells can be identified.
Further surgery ("second and or subsequent stages")
If there is any residual cancer, the wound is re-anaesthetised and further tissue corresponding precisely to the area of positivity is excised and again microscopically checked. This process continues until the operating doctor is satisfied that no cancerous cells remain.
Once the cancer is shown to be completely removed, the patients wound is repaired. There are many ways in which the post Surgery wound can be repaired including:
- Granulation (“healing by itself”)
- Simple side to side closure
- Skin flaps where adjacent skin is utilized to cover the defect.
- Skin graft
- Combinations of the above
- Once the wound has been repaired the patient is discharged home.
- The patient will usually return at one to two weeks for removal of stitches and thereafter on an as required basis.
Almost certainly following Delayed Margin Control Surgery the cancer in that site will be cured. The final functional and cosmetic outcome is usually significantly better than standard excision with wide excision.