Post-Mohs Surgical Defect Repair with Dehydrated Human Amnion-Amnion

Skin cancer is a worldwide heterogeneous collection of cancers compromising melanoma and non-melanoma, predominantly affecting geriatric patients ages 65 and older, and represents a challenge in clinical management [5]. Mohs micrographic surgery (MMS) is a clinical procedure implemented in the treatment of various forms of non-melanoma and melanoma skin cancers; the process involves removing thin layers of visible cancer tissue and analyzing the tissue margins until all cancerous tissue has been removed [18]. To date, there exists no standard for post-operative wound management following MMS; to achieve optimal recovery, the patient and surgeon have a myriad of available options for treatment. This retrospective clinical case study demonstrates the effectiveness of dehydrated human amniotic membrane allografts (Axolotl DualGraft™) as a treatment modality for successful wound closure and healing in various post-Mohs secondary intention wounds. A plastics reconstructive surgeon with Heartland Plastic & Reconstructive Surgery P.C. utilized amniotic membrane (AM) allograft as a vulnerary modality for distinctive post-Mohs wounds from diverse geriatric patients. Further investigation for the optimal application in a controlled study using dehydrated amnion-amnion membrane for post-Mohs surgical wounds should be considered based on these data.


Introduction
Mohs micrographic surgery (MMS) is the standard care for high-risk basal cell carcinoma, squamous cell carcinoma, and other primary or recurrent contiguous skin cancers, such as melanoma or, occasionally, Merkel cell carcinoma.[1,7,20] MMS was initially developed by Dr.
Frederic E. Mohs at the University of Wisconsin in the 1930s, initially dubbed chemosurgery using a zinc chloride paste.Currently, the technique excises thin layers of cancer tissue with minimal removal of the surrounding healthy tissue.The procedure is generally executed while the patient is conscious, with the malignant tissue area numbed by anesthesia injections, and can last several hours.[1,11] A small margin of normal-appearing tissue is traced around the cancer, and during excision, the tumor and the narrow margin are removed, and the sample is sent to an onsite laboratory for thin sections to be histopathologically analyzed.If residual cancerous cells remain within the tissue section margins, additional excision will occur, and the new margins will be analyzed until the tissue margins are lesionfree.In general, this procedure is associated with superior cure rates, sparing normal healthy tissue, and is becoming widespread amongst the dermatological community worldwide.[1,20] Due to the rising epidemic of skin cancer and an increase in the number of trained dermatologists in MMS, the use of this treatment modality has expanded exponentially since the 1930s.[1,11] As the number of MMS procedures increases, establishing an optimal treatment for post-Mohs surgical defects to ensure the return of healthy native tissue while avoiding the recurrence of skin cancer is the next step toward a successful outcome in the MMS field.
Following the procedure, the patient and surgeon can discuss care for the post-Mohs wound.Ultimately, the result is to aid in the closure of the surgically created wound; however, no standardized post-MMS care exists.Most post-Mohs wounds are repaired at the end of the surgery.
If it is a large or complex wound, the surgeon may temporarily close it using sutures until another repair operation can be completed.
Depending on the characteristics of the post-Mohs wound (including the size and location of the wound, the discomfort experienced by the patient, and the availability of materials), post-surgical treatment

Abstract
Skin cancer is a worldwide heterogeneous collection of cancers compromising melanoma and non-melanoma, predominantly affecting geriatric patients ages 65 and older, and represents a challenge in clinical management [5].Mohs micrographic surgery (MMS) is a clinical procedure implemented in the treatment of various forms of non-melanoma and melanoma skin cancers; the process involves removing thin layers of visible cancer tissue and analyzing the tissue margins until all cancerous tissue has been removed [18].To date, there exists no standard for postoperative wound management following MMS; to achieve optimal recovery, the patient and surgeon have a myriad of available options for treatment.This retrospective clinical case study demonstrates the effectiveness of dehydrated human amniotic membrane allografts (Axolotl DualGraft™) as a treatment modality for successful wound closure and healing in various post-Mohs secondary intention wounds.A plastics reconstructive surgeon with Heartland Plastic & Reconstructive Surgery P.C. utilized amniotic membrane (AM) allograft as a vulnerary modality for distinctive post-Mohs wounds from diverse geriatric patients.Further investigation for the optimal application in a controlled study using dehydrated amnion-amnion membrane for post-Mohs surgical wounds should be considered based on these data.modalities may include further surgical intervention using autologous skin grafting, closing the wound with sutures, pulling skin from nearby to cover the wound, tissue reconstruction, secondary intention healing, or the currently explored method of applying a biological tissue product, such as amnion tissue.The mechanisms of healing depend on the tissue layers involved (partial vs. total thickness) and the mechanism of wound closure (primary, secondary, or tertiary intention).Critical factors within this repair process include cells that generate the tissue and establish a clean wound bed, the growth factors and cytokines that control cellular activity, and the extracellular matrix that provides the necessary wound-healing environment that promotes cell migration and contains several substances that regulate the migration and activity of the growth factors and cytokines present.For patients who are adverse to and decline further surgical intervention after initial MMS, the alternatives include second-intention healing with or without adjunctive therapy or the application of biological tissue membranes.
The benefits of using biological skin substitutes include the construction of natural dermis due to the native extracellular matrix structure and a basement membrane, a collection of growth factors, and antimicrobial properties.These products have shown efficacy in protecting wounds as a structural barrier or covering, reducing the bacterial load, controlling inflammation, and encouraging angiogenesis.[15,24] In this paper, we present a retrospective analysis of six patients who received biologic amniotic tissue grafts to post-Moh's surgical defects to assist and support the healing of the surgical site.This data suggests that biological amnion may be a minimally invasive clinical option, allowing physicians to have a post-MMS standard of care.It is suggested that a further multi-site, controlled clinical study should be explored based on the data herein.

Process of Manufacturing Amnion-Amnion Membrane:
For many years, the human amniotic membrane has been utilized in many clinical applications.This biological intervention is derived from the inner and outer layers of donated human placental tissue that consists of two essential tissue layers known as the amnion and chorion.The amnion and chorion membranes maintain the necessary environment and protect the fetus during gestational

Study Setting & Patient Selection:
The study occurred at Heartland Plastic & Reconstructive Surgery P.C. in Des Moines, Iowa.To ensure accurate and transparent reporting prior to the preparation of this retrospective case series, written consent was obtained from the patients, allowing for the use of de-identified personal health information and photographs, along with publication rights.Patients were included if the diagnosis was comprehensive, treatment was completed with Axolotl DualGraft TM , and the representative photos of different healing time intervals were clear and discernible.The demographic age group of the patients treated within this study ranged from 67 to 91 years old, with all patients having a different location of surgical intervention, see Table 1.Complications and self-reported issues after receiving MMS treatment are common in elderly patients, and the delay to beneficial and more intensive treatments may be a risk factor.Age and previous surgical or medical conditions can alter tissue characteristics and complicate or delay healing.Further investigation in difficult-to-heal tissue locations may demonstrate further intention of healing with biological tissue grafts.In this study, the patient defects range from full-thickness scalp wounds to neck, cheek, and hand post-MMS defects.

Method of Application:
Following an explanation of treatment and patient consent, an initial assessment of the post-Mohs wound occurred.A small amount of damage debridement was done with blunt dissection using tissue forceps around the wound margins to remove necrotic and scab or eschar tissue formation that would prevent further healing.Sterile normal saline (0.9 % sodium chloride) was utilized to moisten the clean membrane sample before transferring with tissue forceps into the flat section of the wound.It is important to note that the membrane was not packed into the damage, and there is no directional issue of the application using Axolotl DualGraft TM , it being an omnidirectional membrane.After application, the membrane was not affixed to the tissue, as it naturally adhered to the wound bed due to wound, the surgical option was denied and permission for application of biological allograft was granted.Initial examination of wound measured to be 6.8x7.6x1.0 cm area of a full-thickness, non-healing scalp wound with exposed bone.Wound margins are exposed and identifiably healthy, without evidence of undermining or tunneling.
Acute infection was not present, and the wound was moist with a nonpurulent, sanguineous exudate.The coloration was normal, based on wound presentation.Using aseptic technique, the amniotic membrane product was initially pre-soaked with a 0.9% sterile normal saline solution.The moistened amniotic membrane was then aseptically placed within the wound margins, without fixation.Following clinical application of the membrane product, the wound was observed for a two-week period, with reapplication performed, as needed.By week 5 of treatment, tissue granulation commenced, starting at the wound edges, with full granulation tissue coverage complete by week 9, at which time, no exposed bone was observed.

development. [ 12 ]
To date, various methods have been utilized to prepare, preserve, and sterilize amnion-based membranes, resulting in a unique allograft product with different morphological, mechanical, and biological properties.[24,25,26] The allograft membrane elected for application in this clinical study was Axolotl DualGraft TM , a bi-layered dehydrated human amnion membrane allograft derived from the amniotic lining of the placenta.This specific allograft source material is donated placental tissue collected from consenting mothers and is prepared accordingly.Upon receipt, the tissue is rinsed with sterile saline to remove residual blood and tissue debris, and then the amnion and chorion layers are separated via blunt dissection.The amnion layer is inspected for tears or damage and then further washed before folding the spongy intermediate layers together, with the epithelial surface facing outwards.Then, the membrane is smoothed to remove air pockets and ensure complete contact before being transferred to a drying rack and air-dried for a period.After dehydrating the membrane, it is cut to specific membrane sizes, packaged, and terminally sterilized using gamma irradiation.The final product results in a dual-layered membrane with the amnion epithelial surface exposed on each side for an omni-directional implantation method.Axolotl DualGraft TM is regulated solely under section 361 of the Public Health Service (PHS) Act, classified as minimally manipulated tissue, and follows FDA 21 CFR Part 1271 code of federal regulations (CFR).Axolotl DualGraft TM is indicated for full or partial-thickness, chronic and acute wounds, and maintains the ability of the structural tissue to act as a barrier.

Case 1 :
photos of healing taken at each visit.The reapplication of Axolotl DualGraft TM was completed based on the physician's discretion.