1. Summary of cases.
(1) Case 1.
Male, 39 years old. Painless lump on the external nose increased progressively for one year. One year ago, a sesame-sized nevus was found on the right nasal dorsum, with itchy sensation, easy bleeding when scratched, no redness, swelling and pain, and slowly increasing in size. On admission, the general condition was good, and no enlargement of superficial lymph nodes was detected. A 10-mm diameter round mass was seen in the lower part of the right nasal dorsum, which was locally elevated above the skin in the shape of a small mound, with clear borders and a central part that did not heal. Preoperative hepatobiliary, pancreatic, splenic, renal and retroperitoneal ultrasound, skull base to supraclavicular enhanced CT and chest radiograph were performed to exclude the possibility of distant metastasis.
Intraoperative frozen pathological section showed that the mass was basal cell carcinoma, and all the margins (four margins at 5mm from the outer edge of the mass and one basal margin at the base of the cut to the cartilage) were negative. No local recurrence and no systemic metastasis were seen at the postoperative follow-up of 3 months, and the patient was very satisfied with the good local appearance.
(2) Case 2.
Female, 73 years old. A painless external nasal mass with progressive increase in size for more than 2 years. Two years ago, a mass of about 5 mm in size was found on the back of the nose without painful itching and denied a history of bleeding from ulceration. Six months ago, he underwent nasal mass excision in an outside hospital and the postoperative pathology was unknown. However, the mass reappeared after the operation, initially slowly increasing in size, and recently rapidly increasing in size, so she came to our hospital. The patient had a history of hypertension and heart disease. On admission, the general condition was good, and no superficial lymph nodes in the body were significantly enlarged. A 30-mm diameter mass was seen in the lower part of the right nasal dorsum, which was locally elevated in a hemispherical shape, without ulceration, redness, swelling and pain, and no limited protrusion in the nasal cavity. The possibility of malignant tumor was considered preoperatively, so hepatobiliary, pancreatic, splenic, renal and retroperitoneal ultrasound, skull base to supraclavicular enhanced CT and chest radiograph were performed to exclude the possibility of distant metastasis.
After controlling hypertension with medication and treating heart disease, “external nasal tumor resection + expanded interbrow flap and nasolabial advancement flap repair” was performed electively under general anesthesia, and intraoperative frozen pathological section confirmed that the mass was basal cell carcinoma, and all the margins (four margins were taken at 5 mm from the mass, and one basal margin was taken at the base of the cut to the cartilage) were negative. The margins (upper, lower, left and right margins at 5 mm from the mass, and one basal margin at the base of the cartilage) were negative. The local flap healed well after surgery (Figure 2: Case 2 preoperatively), and the patient was very satisfied with the appearance after removal of the stitches.
2. Overview
(1) Basal cell carcinoma (BCC), also known as basal cell epithelioma, is one of the most common malignant tumors of the skin, accounting for about 60%. The incidence of BCC has significant regional, ethnic and skin color differences. Light-skinned people with blue eyes and white skin are prone to skin cancer, and its incidence rate is more than 45 times that of non-white people, while it is rare in black people; the incidence rate is higher in men than in women. The incidence rate is higher in males than in females, and it is more common in older than in younger people. There is a lack of relevant epidemiological data in China.
(2) UV radiation is currently considered to be the main predisposing factor for the development of BCC, and this may increase the risk of BCC in patients with a family history of skin cancer. Other non-UV environmental factors include ionizing radiation, various harmful chemicals and dust, and exposure to arsenic agents may trigger BCC. In addition, a number of genetic disorders are associated with the risk of BCC, including albinism, pigmented dry skin disease, Buzzex syndrome (eczematous or psoriasis-like lesions on the ears, nose, cheeks, hands, feet, and knees in patients with respiratory or digestive tract tumors), and Grimm’s syndrome (basal cell nevus syndrome).
(3) The occurrence of BCC is also the result of a combination of genetic and environmental factors, and although much progress has been made in the study of pathogenesis, it is not yet well understood. The known genes include P53, P16, PTCH, Fas/FasL, and c-fos proto-oncogene. In addition, abnormal expression of vascular endothelial growth factor (VEGF), cell proliferation nuclear antigen (PCNA), etc. is also associated with BCC.
(4) BCC is often classified into four clinical types: superficial, nodular (or cystic), pigmented and scleroderma-like. The nodular type is commonly seen on the face and often presents as a single shiny red nodule with markedly dilated capillaries in the periphery. Clinically, it is mainly distinguished from the following diseases: squamous cell carcinoma, malignant melanoma, melanoma nevus, psoriasis, eczema, etc. Definitive diagnosis is based on intraoperative and postoperative pathology.
(5) Current treatment options include surgical and non-surgical therapies. Surgical treatments include laser, cryotherapy, traditional surgical excision, and Mohs microsurgery. Non-surgical treatments include radiation therapy, photodynamic therapy, and drug therapy. The preferred treatment option is still early surgical removal of the tumor. Radiotherapy can be applied to some elderly patients or when the lesion is too large for surgical treatment.
3.Treatment insight.
(1) Key points of surgery.
Head and face surgery is not only to remove the tumor completely but also to repair it at the same time to reduce the impact on appearance. Most BCCs have pathological limitations and minimal metastasis in biology, so theoretically, it is sufficient to achieve safe margins without expanding the surgical scope. In general, resection of superficial, nodular and pigmented BCCs is feasible at 4-5 mm from the outer edge of the tumor. Intraoperative frozen section of the margins is particularly important as a definitive safety boundary, and the majority of head and neck surgeons abroad use intraoperative frozen section to determine the status of the margins.
A facial disinfection is performed and a circular marker is made 5 mm along the edge of the mass. The incision is made along the outer edge of the marker, with a deep level cut to the cartilage surface and a cylindrical excision of the tissue within the marker. A point above and below the trauma edge was chosen to cut the strip of whole tissue to send four margins, and the tissue of the cartilage surface was cut at the base to send the basal margin, for a total of five margins. The frozen section reported that the masses were all basal cell carcinoma, and all the margins were negative in case 1; in case 2, only the left side margin was positive, so the left side was excised again with 3 mm wide whole layer of tissue, and the new trabecular margin was then cut with strips of whole layer of tissue and sent to the frozen section for the second time, and the frozen margin was negative.
(2) Key points of repair of adjacent tissue flaps.
Case 1: Since the local defect in this case was located on the right side of the median line of the nasal dorsum with a diameter of 20 mm, an enlarged interbrow flap was prepared as planned, an incision was made, and the flap was carefully separated under the superficial layer of the nasal muscle, taking care not to damage the lateral nasal artery and the dorsal nasal artery present on the surface or deep in the fascial layer to avoid damaging the blood supply of the flap. Care is taken that the apical triangular area is not too low so as not to interfere with the transverse blood supply to the tip. The facial flap should be lifted in the plane of dissection for facial debridement. If there is local bleeding, bipolar electrocoagulation is applied to stop the bleeding and avoid postoperative hematoma. A rotating flap combined with a V-Y suture is applied in this case. Care should be taken to avoid suturing under tension when closing the subcutaneous layer (5/0 absorbable sutures) and closing the skin (6/0 non-invasive sutures).
Case 2: The local defect amounted to 40 × 36 mm, and the left side was already about 6 mm past the midline and the right side was already about 6 mm past the nasolabial fold, so two local flaps were chosen for repair. One was the enlarged interbrow flap mentioned above, which was used to repair the defect near the midline, including the part of the defect to the left of the midline; the other was the nasolabial fold flap, which was intended to repair the defect of the right nasal dorsum. For the lower nasal and nasal wing defects, the nasolabial flap is preferably used. This flap is supplied by the medial canthal artery of the facial artery or its branches, and crucially, the vertical subcutaneous tip of the flap confers greater mobility and a stable blood supply to the flap. An enlarged interbrow flap is prepared first, and then the size and advancement distance of the nasolabial flap to be prepared are estimated, thus avoiding the need to repair large defects with a small flap. The subcutaneous incision for the preparation of the nasolabial flap should reach the level of the muscle layer. The key points in flap suturing are the same as described above.
(3) Causes of failure of adjacent tissue flap surgery.
Repairing a large defect with a small flap (design error)
Hematoma (technical error)
Damage to the blood supply (technical error)
Flap design beyond the blood supply (design error)
The wound is sutured under tension, or the flap’s tip is too short (technical error)
Some physicians believe that the easiest way to remove the tumor is to perform a skin graft, which may limit the depth of excision in order to preserve the vascular layer needed for the skin flap to be viable. In terms of function, a local flap is superior to a skin flap because there is little or no scar contracture, and it can prevent lip ectropion, lid ectropion, tear spillage, and loss of orofacial function. The flap has normal skin color and texture, which is a good solution to the patient’s aesthetic problems, and full-layer defects of the nose, lip, eyelid, and auricle must be repaired with a flap.
The surgical treatment of BCC requires knowledge of otolaryngology, oncologic surgery and plastic surgery, and the operator should have experience in applying local flaps and have the ability to design the surgery carefully. It is the higher pursuit of our otolaryngology head and neck surgeons to completely remove the tumor and avoid recurrence, while minimizing the impact of surgery on the appearance.