Second primary squamous cell carcinoma arising in a skin flap: a case report and literature review on etiologic factors and treatment strategy

Clinical and pathological features of second primary neoplasms arising in head and neck reconstructive skin flaps

The incidence of second primary neoplasms arising in the skin reconstructive flap (SNAF) is increasing because of the increase in head and neck flap reconstruction and cancer survival. Prognosis, optimal treatment, and their clinicopathological-genetic features are under debate and are difficult to diagnose. We retrospectively reviewed SNAFs based on a single center's experience over 20 years. Medical records and specimens of 21 patients with SNAF who underwent biopsies between April 2000 and April 2020 at our institute were retrospectively analyzed. Definite squamous cell carcinoma and the remaining neoplastic lesions were subclassified as flap cancer (FC) and precancerous lesions (PLs), respectively. Immunohistochemical studies focused on p53 and p16. TP53 sequencing was conducted using next-generation sequencing. Seven and 14 patients had definite FC and PL, respectively. The mean number of biopsies/latency intervals was 2.0 times/114 months and 2.5 times/108 months for FC and PL, respectively. All lesions were grossly exophytic and accompanied by inflamed stroma. In FC and PL, the incidences of altered p53 types were 43% and 29%, respectively, and those of positive p16 stains were 57% and 64%, respectively. Mutation of TP53 in FC and PL were 17% and 29%, respectively. All except one patient with FC under long-term immunosuppressive therapy survived in this study. SNAFs are grossly exophytic tumors with an inflammatory background and show a relatively low altered p53 and TP53 rate and a high p16 positivity rate. They are slow-growing neoplasms with good prognoses. Diagnosis is often difficult; therefore, repeated or excisional biopsy of the lesion may be desirable.

Hypopharyngeal Skin Cancer Following Total Laryngectomy and Pectoralis Flap Reconstruction: Case Report and Literature Review

Although early complications of microvascular free flaps and regional pedicled flaps of the head and neck are well described in the literature, there is relatively limited knowledge regarding their long-term complications. We describe the case of a 62-year-old gentleman who underwent primary resection and adjuvant radiation therapy for supraglottic squamous cell carcinoma who subsequently underwent salvage total laryngectomy with pectoralis major muscle flap reconstruction. During a later esophageal dilation for complaints of dysphagia, a new exophytic lesion of the hypopharynx was biopsied on endoscopy. The lesion was excised via transoral robotic surgery with final pathology revealing squamous cell carcinoma completely confined to the skin paddle of the pectoralis flap and arising from the epidermis of the skin flap. No further therapy was undertaken and there has been no evidence of recurrence 2 years after resection. Synchronous cutaneous malignancy is a rare complication of free and pedicled flap reconstruction, however its diagnosis is increasing. Given the concern for recurrent mucosal tumors arising in the upper aerodigestive tract which may require extensive resection with or without adjuvant therapy, it is important to determine the etiology of the underlying malignancy to guide appropriate treatment.

Pathologic Surface Changes in the Submental Flap Used for Intraoral Reconstruction: Report of Two Cases

Soft tissue reconstruction is often necessary after pathologic resection of oral squamous cell carcinoma. Although morphologic changes are common after transfer of the flaps to the oral cavity, pathologic changes within the transferred flaps, used for intraoral reconstruction, are rare events. Despite the widespread use of submental flap for oral cavity reconstruction, there are no reports in this respect. In this article, pathologic changes in the surface epithelium of transferred submental flaps are demonstrated with the report of two cases. The occurrence of lichen planus in a submental flap that had been used for reconstruction of lateral tongue border is reported in one case and in another patient, squamous cell carcinoma arising in the transferred de-epithelialized submental flap, used for maxillary and buccal reconstruction, is shown.