Congenital melanocytic giant nevus on the back of a baby: Early excision by power‐stretching and result after 14 years

Opinion in the literature is divided on whether or not to remove congenital melanocytic giant nevi.1 The boundary is fluid and depends on the size of the nevus, the location and experience of the surgeon to whom the child is referred, and the mindset of the parents.2 Options include stretch plasty, expander techniques, full-thickness and split-thickness skin graft coverage. Dermabrasion has no lasting effect.1 Some congenital giant nevi are inoperable. However, removal of areas with an increased likelihood of developing melanoma is advisable. Individual case assessment is always necessary. Here we show a case with complete documentation in which early excision with stretch plasty was used in stages under tension. This procedure has long been established in our clinic and has also been applied successfully in many other children. However, it is important to note that not all cases showed the desired result. The rationale behind this technique is the double-butterfly suture technique, which can withstand high tensions during skin wound closure due to firm anchoring in the corium and the pulley effect.3-5 It was further developed by the first author of this publication based on the butterfly suture he developed for aesthetic wound closure as a doubling with the pulley effect for high tension. This made it possible to avoid major surgical procedures when closing defects after tumor excisions. The procedure has been used thousands of times with good aesthetic results. A demand for tension-free wound closure has thus been refuted. The method is based on the excision of sections at the edge of the nevus, primarily in order to stretch the surrounding healthy skin. Narrow margins of the nevus must be spared when planning, since here, initially, the sutures do not damage any healthy skin, although nevus skin is usually not as robust as healthy skin. For smaller such nevi, generous application of tumescent local anesthesia is performed along the planned incision at the edge of the nevus using an infusion device. This is tolerated by the children without causing pain, using a mixture of lidocaine and ropivacaine. It is prepared in the pharmacy and strongly diluted with adrenaline in isotonic solution (Table 1). It has a very long duration of action and can also be used in infants.6-8 In the present case of an extended nevus, the operation was performed under general anesthesia. The additional local anesthesia along the planned incisions as mentioned above served to reduce wound edge bleeding and eliminate postoperative pain for up to six hours. After the incision, the surrounding skin was extensively mobilized and then drawn over the nevus as far as possible using hooks. The elastically stretchable nevus is also pulled towards the edges of the wound to determine the maximum extent that can be removed. The area is then removed after local anesthesia of the now defined resection line. The individual areas are resected one after the other so that the maximum traction on the nevus is not exceeded. The wound is closed using an oblique inserted double-butterfly suture extending beyond the surface of the nevus. This angled insertion allows the suture to be anchored as broadly as possible in the entire corium, together with a pulley effect (Figure 1a). The suture material is polydioxanone, a resorbable monofilament material with high tensile strength (size 2-0) and no tissue reaction.3 The procedure begins in the center (Figure 1b) to ensure successful bridging. The traction on the wound edges is enormous and one can see a blanching of the skin, which however, quickly subsides as the healthy skin stretches during the operation (power stretching). After the central suture, the closure is completed from both sides. A Redon drain is inserted only if necessary. The result is the described skin bulge (Figure 1c). Post-operative bleeding from the corium is minimized by using a continuous, overlying securing suture made of rapidly resorbable, size 6-0 suture material (polyglactin) on the surface. Finally, the suture is protected with transverse suture strips (Figure 3d), and a layer of a non-adhesive, fat-free dressing (Adaptic®) is applied over this to prevent blood from adhering to the bandage. Compresses and a pressure bandage are then applied, followed by a polyester cast adjusted intraoperatively, if necessary. These layers ensure a pain-free initial dressing change, usually after three days. In May 2010, a female infant from Saxony was born with a congenital melanocytic giant nevus that took up almost the entire back and parts of both flanks (about 20% of the body surface; Figure 2a). The girl was first presented to us in July 2010, after an MRI had already been performed under anesthesia at the University Hospital of Leipzig to rule out neurocutaneous melanosis. The nevus left only a small amount of healthy skin at the shoulders and up to the gluteal fold. However, our experience with early excision showed that, especially in very young children, the healthy skin is highly stretchable and can even grow back under tension. After providing thorough patient education, we scheduled the first excision series for November 2010. This was carried out as shown in Figure 2a. The dotted lines show the extent of the mobilization of the surrounding skin, and the hatched areas are the areas to be resected. The operation was performed as described in the methods section. The child could be discharged after the first dressing change. The considerable distance to his home town made close follow-up care impossible. During the course of the disease, a dehiscence occurred in the upper back area, a not uncommon complication, but one that could be managed locally. A secondarily healed dehiscent scar remained, but without any loss of healthy skin (Figure 2b), and this was then taken into account for the following surgeries (Figures 2b,c). Figures 2b,c depict the three subsequent interventions schematically. It can be seen that the remaining nevus area was also stretched. The second (March 2011) and third (July 2011) procedures were not performed in the area of the dehiscence scar (Figure 2b,c). Following the third operation, the child was discharged with a Redon drain in place, which she accidentally removed herself after a few days without any further complications. During the fourth procedure (November 2011), most of the scar tissue could be resected (Figure 2c). The result after the fourth operation is shown in Figure 3a. Only hyperpigmentation and a small scar dehiscence are still visible. Small wound dehiscences were also present at individual sites after the interventions (Figure 2b,c), but these always healed secondarily. After the fourth resection, a local wound infection occurred that had to be treated with antibiotics. Because of his liveliness, the child wore a polyester cast on his back during the day, which was repeatedly adjusted intraoperatively, for two years. Due to residual scarring, a further corrective procedure was performed in August 2012 (Figure 3a–d). In this procedure, the double-butterfly sutures were set completely intracutaneously, as they had been in the fourth procedure, and the superficial continuous suture described above was placed not overlying but instead intracutaneously with a thin polydioxanone (6-0). The result after one year, without further corrections, is shown in Figure 4a and after 14 years in Figure 4b. The decision for surgery of such large melanocytic nevi is made on an individual basis.1 Our experience with early excision has consistently been positive, as the skin of infants and young children still stretches very well and apparently also regrows.2, 8, 9 The high tension is well tolerated by the skin.1, 9 In young children, the implantation of an expander is technically difficult10 and is particularly problematic if the child's place of residence is very distant. In most cases, the required surface area for implantation is also lacking. In this case, an MRI was performed to rule out neurocutaneous melanosis, as recommended in the literature.11 In our opinion, however, this should be an individual decision, similar to the treatment planning for the nevus. As this illustrative example shows, power stretching may also have complications. We have therefore presented them here. In our experience with many such operations, there were never any critical situations, since even areas that had ruptured always healed without secondary pain if good dressing technique was used. However, they did make planning a little more difficult. Of course, assistance from especially the parents was strongly encouraged. Even skin necrosis cannot be ruled out completely, but in our medical records has been a unique event only. In this case, secondary healing was also possible, although healthy skin is lost as a result. Conditions for success are a very good patient education with a description of the planning and complications, as well as empathy with parents and child. Minimizing pain pre- and postoperatively is the top priority for children. The incision line is infiltrated with the described mixture of local anesthetics and adrenaline.6, 7 The stretchability of the skin after mobilization was tested using opposing hooks. We always used the oblique inserted double-butterfly suture with maximum possible anchoring in the dermis within the nevus (Figure 1a–c).5, 10 An additional continuous suture was made at the raised upper wound edge to reduce postoperative blood leakage. To avoid the pain in removal, resorbable suture material was used. The subsequent superficial cutting of individual protruding lumps is usually well tolerated. It is important to use the low-pain dressing technique described above, as our many years of experience have shown that children are less anxious at their second appointment. In this case, complications arose which were partly due to the child's above-average agility. However, these were ultimately successfully overcome with the support of the family. She reports no psychological problems and, as far as melanoma development is concerned, has a risk comparable to that of the normal population, also because she consistently adheres to the dermatological guidelines on sun protection. We would like to thank the child's family for their kind co-operation. Open access funding enabled and organized by Projekt DEAL. None.