Cyclin D1 and PRAME expression in distinguishing melanoma in situ from benign melanocytic proliferation of the nail unit.

BACKGROUND: Distinguishing benign lesion from early malignancy in melanocytic lesions of the nail unit still remains a diagnostic challenge, both clinically and histopathologically. While several immunohistochemistry (IHC) stainings have been suggested to help discriminate benign subungual melanocytic proliferation (SMP) and subungual melanoma in situ (MIS), the diagnostic utility of IHC staining for cyclin D1 and PRAME has not been thoroughly investigated in melanocytic lesions of nail unit. METHODS: This retrospective study included cases of benign SMP and subungual MIS confirmed by biopsy at Asan Medical Center from January 2016 to December 2020. Cases of melanocytic activation without proliferation and melanoma where dermal invasion was identified were excluded. Cyclin D1 and PRAME expression was assessed by counting proportion of melanocytes with nuclear positivity under 200x magnification. RESULTS: A total of 14 patients with benign SMP and 13 patients with subungual MIS were included in this study. 11 patients with benign SMP (71.4%) and 5 patients with subungual MIS (38.5%) showed > 60% nuclear immunostaining for cyclin D1, respectively. While 13 patients with benign SMP (92.9%) showed totally negative staining for PRAME, 10 patients with subungual MIS (76.9%) exhibited > 50% nuclear immunostaining for PRAME. Using the cutoff of 10%, PRAME exhibited good overall discrimination between benign SMP and subungual MIS (AUC = 0.849, 95% CI = 0.659-0.957). CONCLUSIONS: This study suggests that PRAME IHC staining as a reliable discriminator in distinguishing subungual MIS from benign SMP.

Granulomatous Reaction to Dermal Injection of Growth Factors from Umbilical Cord Blood-Derived Mesenchymal Stem Cells: A Case Report.

Use of stem cells to treat various diseases in dermatology has been of interest. Conditioned media with the growth factors secreted from stem cells has been used as a topical agent. We report a case of foreign body granulomas that appeared days after dermal injection of the conditioned media mimicking scars at all injection sites.

Partial unilateral lentiginosis: a clinicopathological analysis of 32 cases on the head and neck area in Korea.

BACKGROUND: Partial unilateral lentiginosis (PUL) is a rare acquired circumscribed hyperpigmentation characterized by multiple simple lentigines involving half of the body. Since the previous studies of PUL were mostly based on case reports and the current literature lacks well-designed retrospective studies that involve a large number of cases, PUL is not a well-defined entity, and differential diagnosis with nevus spilus is still difficult. This study aims to evaluate clinical and histopathological characteristics and treatment outcomes of PUL on head and neck area of Koreans. METHODS: Thirty-two patients with PUL on head and neck area were diagnosed clinicohistopathologically at the Asan Medical Center from 2004 to 2017. Their medical records, photographs, and biopsy specimens were reviewed, and immunohistochemical staining for protein kinase C (PKC)-ßΙΙ was evaluated for melanogenic activity. RESULTS: Four patients (12.5%) of PUL had congenital lesions, and 24 (75.0%) had age of onset younger than 10 years. Confluency of lentiginous lesions (100%) and mild to moderate background interlesional hyperpigmentation (90.6%) were observed. The lentiginous lesions showed increased melanocytes, melanophages, basal melanins, lentiginous hyperplasia, and perivascular inflammatory cells compared with background interlesional hyperpigmentation, and PKC-ßΙΙ was focally positive in 7 of 12 stained PUL lesions. Among the 16 patients who received laser treatments, 10 (62.5%) showed more than 50% of improvement. CONCLUSIONS: The findings of this study will allow for improved diagnosis of PUL and understanding of its features, which may facilitate proper management in the future.

A Large Scalp Defect Coverage With Pedicled Free Flap Using the Wrist as a Free Flap Carrier.

The absence of an adequate recipient vessel for free flap pedicle anastomosis near local defect sites discourages surgeons from performing free flap transfers over the scalp because of the challenging neck dissection and the thrombogenic potential of vein grafts for pedicle elongation. We present a case in which a large scalp defect was successfully reconstructed using the wrist as a "free flap carrier," which is an alternative method. A 78-year-old patient with a totally occluded common carotid artery presented to our clinic with a large scalp defect. Reconstruction of the scalp defect was performed in a 2-stage procedure. In the first stage, a free latissimus dorsi (LD) muscle flap was transferred to the defect site, and the pedicle anastomosis was held at the ipsilateral wrist to provide inflow and outflow of blood through the radial artery and vena comitante and cephalic vein that were anastomosed to the flap pedicle. After subsequent split-thickness skin graft, the elevated position of the arm was achieved using a splint and sutures for 3 weeks. In the second stage, the flap was divided, and an additional skin graft over the flap division site and radial artery repair with vein graft was performed. Successful coverage of the scalp defect was confirmed on postoperative day 14 of the second procedure with no complications.