Nodular skin lesions: correlation of reflectance confocal microscopy and optical coherence tomography features.

BACKGROUND: Nodular lesions have common clinical appearance but different prognoses. Differential diagnosis between melanoma (MM), basal cell carcinoma (BCC) and dermal naevus (DN) poses a challenge in clinical practice. Reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) are promising non-invasive imaging techniques, potentially able to decrease redundant biopsies. RCM allows in vivo visualization of skin down to the papillary dermis at almost histological resolution, while OCT, particularly dynamic OCT (D-OCT), provides images deeper within the dermis and reveals the vascular pattern. OBJECTIVES: To identify correlating features observed with RCM and OCT associated with the different nodular lesion diagnoses. METHODS: We retrospectively assessed 68 nodular lesions (30 MM, 20 BCC and 18 DN) with RCM and subsequently OCT. At the end of the study, evaluations were matched with histopathological diagnosis and statistical analysis was performed. RESULTS: In MM, 57% (17/30) evidenced both cerebriform nests at RCM and icicle-shaped structures at OCT, with higher average Breslow index. In 80% of BCCs with basaloid islands at RCM, OCT showed ovoid structures. More than half of DN (56%) showed hyporeflective nests at OCT and either dense nests or dense and sparse nests at RCM. CONCLUSIONS: The combined use of RCM and OCT offers a better understanding of the morphological architecture of nodular lesions, correlating RCM parameters with OCT and vice versa, assisting in turn with early differential diagnosis of malignant and benign nodular lesions. The correlation between icicle-shaped structures and cerebriform nests in MM and their association with Breslow index requires future research.

False-positive iodine-131 whole body scan due to a benign dermal lesion; intradermal nevus ((131)I uptake in a benign nevus).

Whole body radioiodine scanning (WBS), along with plasma thyroglobulin level, remains a reference method for detecting residual or metastatic differentiated thyroid cancer, however, false-positive WBS is not uncommon. External contaminations by body secretions or excretions, inflammation, and cystic structures mimicking metastases in WBS have been reported. Various benign and malignant tumors having different histopathological natures accumulate radioiodine, but intradermal melanocytic nevus was not previously described in the literature, as far as we know. This report describes an unusual cause of false-positive WBS after radioablation therapy due to an intradermal nevus, and the possible mechanisms are discussed.

Spinal neurocutaneous melanosis without cutaneous nevi.

STUDY DESIGN: A case report of spinal neurocutaneous melanosis without cutaneous nevi. OBJECTIVE: To show a case and review the epidemiology, diagnosis and treatment of neurocutaneous melanosis without cutaneous nevi. SUMMARY OF BACKGROUND DATA: Neurocutaneous melanosis is a rare congenital syndrome consisting of benign or malignant melanocytic tumors of the central nervous system and cutaneous nevi. Symptomatic neurocutaneous melanosis has extremely poor prognosis, even in the absence of malignancy. Because leptomeningeal lesions of the neurocutaneous melanosis usually undergo malignant transformation, the life expectancy of almost all patients with malignant transformation is <1 year. In general, patients are treated with palliative therapy, such as shunt placement to reduce intracranial pressure or tumor resection to reduce compression of the brain or spine. METHODS: A 29-year-old man presented with marked hypesthesia and spastic gait. No skin abnormalities were evident. Magnetic resonance imaging (MRI) of the spine revealed intradural tumor at the T5 level. Computed tomography myelography showed intradural extramedullary tumor. Because symptoms progressed, he underwent surgery to decompress the spinal cord. After the pigmented dura was opened, a pigmented tumor was resected. RESULTS: Histologically, the pigmented tumor represented low grade. The pigmented dura and bone comprised melanin-bearing cells without tumor cells. Meningeal melanocytoma with leptomeningeal melanosis in the absence of cutaneous nevi was diagnosed. Neurologic symptoms recovered immediately after surgery. No evidence of local recurrence has been seen after 3 years. CONCLUSION: This patient displayed spinal meningeal melanocytoma and leptomeningeal melanosis without cutaneous nevi. The diagnosis in this case was speculated to represent a forme fruste of neurocutaneous melanosis.

[Objectivity, reproducibility and validity of 3D ultrasound in dermatology]. / Objektivität, Reproduzierbarkeit und Validität der 3D-Sonographie in der Dermatologie.

Recently it has become possible to visualize the three-dimensional (3D) architecture of sonographic structures using high-resolution ultrasound above 20 MHz (Dermascan C, Denmark; DUB 20, Germany). We studied the objectivity, reproducibility, and validity of these two 3D analysis systems on 22 skin tumors. To validate both systems, we compared the sonometric and histometric volume in 4 tumors. The objectivity was calculated by repeated evaluation of the volume on the same serial B-scan sections at 3-month intervals. The two-dimensional B-scans and 3D images exhibited similar characteristics. Volumetric evaluations were reproducible with both systems (variation coefficient < or = 9.9%), when the applicator was oriented longitudinal to the body axis. By changing the orientation, the coefficient increased up to 58.1% (DUB 20). Sonometric and histometric volumes of a phantom model and of the tumors exhibited small deviations in the Dermascan C (< or = 8.1%) and in some tumors large deviations in the DUB 20 (< or = 93.1%). We can conclude that the 3D sonography is a reproducible method, which can be used to evaluate the volume of skin tumors and metastases under chemotherapy or radiotherapy. We suggest in particular to use the in-vivo tumor volume as a prognostic parameter for the malignant melanoma.