Article
Dermoscopy of Spitz Nevus
Spitz nevus usually occurs in children and is seen in about 15% of adolescents. Although Spitz nevus is a benign lesion, its morphology is often very similar to that of malignant melanoma, which is quite difficult to identify and easy to misdiagnose. Dermoscopy combines a microscope with polarized light that filters the refracted light from…
Spitz nevus usually occurs in children and is seen in about 15% of adolescents. Although Spitz nevus is a benign lesion, its morphology is often very similar to that of malignant melanoma, which is quite difficult to identify and easy to misdiagnose. Dermoscopy combines a microscope with polarized light that filters the refracted light from the skin’s stratum corneum to see structures that cannot be recognized by the naked eye, helping doctors better identify Spitz nevi.
Spitz Nevus Overview
Spitz nevus, also known as benign juvenile melanoma, is a benign, sporadic and well-demarcated melanotic lesion composed of bundles of ovoid or spindle-shaped epithelioid melanocytes.
Spitz nevus is often found on the face, but can also be seen on the lower limbs or trunk, and often appears suddenly and enlarges rapidly. It is more common in children and adolescents as a rare melanocytic lesion.
Spitz nevi are highly similar to malignant melanoma and both may present with spindle or epithelioid cells. Atypical Spitz nevi may have certain features of malignant melanoma, such as cellular anomalies, pathologic karyorrhexis, and a high proliferative index, which make the diagnosis more difficult.
Dermoscopy Techniques
Dermoscopy provides a clear view of the skin by filtering out diffuse reflections from the surface of the skin through a polarizing filter and selectively collecting transmitted light.Spitz nevus is a special type of pigmented nevus of the skin, whose morphology and color may vary from one individual to another. Through dermoscopy, doctors can observe the microscopic features of Spitz nevus, such as pigment distribution, vascular structure and skin texture, to assist in determining whether it is a benign lesion.
The probe of the dermatoscope is attached to the skin surface to be observed, keeping the distance between the probe and the skin, and adjusting the focus until the image is clear. Before performing dermoscopy, you should avoid applying medications or cosmetics on the skin surface to avoid physically blocking the light and affecting the imaging.
Dermoscopic Features of Spitz’s Nevus
I. Early stage of growth
Starburst pattern is one of the typical dermoscopic manifestations of Spitz nevus, which is characterized by the presence of regularly or irregularly arranged stripes, dot balls or both around the periphery of the lesion. The spherical pattern is characterized by regular or irregular brown dot balls, which gradually become larger and merge with the growth of Spitz nevus.
II. Growth period
Streaks and punctate balls gradually increase in size and spread around the lesion. In the homogeneous pattern or the dark pigment network pattern, the pigmentation may gradually increase, making the entire lesion area more obvious and prominent.
III. Stable stage
A Spitz nevus may gradually change to a homogenous pattern, manifesting itself as diffuse uniform and structureless hyperpigmentation. In the starburst pattern, as the Spitz nevus stabilizes, the streaks and dot balls may gradually disappear or become less pronounced. This signifies that the growth of the Spitz nevus has stopped or stabilized.
Correlation of Dermoscopic Features and Histopathology of Spitz Nevus
Histopathologically the starburst pattern corresponds to the features of epidermal hyperkeratosis, thickening of the granular layer and epidermal hyperplasia; the uniformly distributed punctate vascular pattern may be related to the formation and distribution of neovascularization in Spitz nevi. In histopathology, neovascularization corresponds to areas of homogeneous dark red; a globular pattern with reticular depigmentation is associated with aggregation of melanin granules. This presentation may be associated with the proliferation and uneven distribution of melanocytes in Spitz nevi.
How to Tell the Difference Between Spitz and Melanoma
Shape: Spitz nevi are usually round or oval with clear edges; whereas melanomas are irregularly shaped with fuzzy edges.
Growth rate: A Spitz nevus grows slowly, whereas a melanoma grows faster and may increase in size rapidly over a short period of time.
Color: Spitz nevi are usually brown or black in color and are more uniform, while melanomas may vary in color and may appear blue, white, and other colors.
A Spitz nevus is a rare benign skin tumor that usually does not require treatment. However, if the mole shows abnormal changes, such as enlargement, color change, or symptoms such as pain, a medical professional will need to evaluate whether treatment is needed.
Spitz Nevus with Other Skin Lesions
Spitz nevus has clear edges, slower growth rate, uniform color and no obvious change in size. Malignant melanoma is irregularly shaped, may have bulges and ruptures on the surface, and grows faster.
Spitz nevus: dermoscopic structural patterns are mainly vascular pattern (pink homogeneous), spherical pattern, starburst pattern, reticular pattern, atypical pattern and pigmented homogeneous pattern.
Malignant melanoma: dermoscopy reveals features such as irregular vascular structures, pigmented networks, blue-white curtains, and areas of asymmetry and structurelessness.
Clinical Case Studies
Dermoscopic images clearly show microstructures and pigmentation below the skin surface, largely compensating for the limitations of clinical visualization. And there is a good correlation between most dermoscopic features and histopathologic criteria.
Guidelines for the Management of Spitz Moles
At the time of the patient’s visit, the physician should perform a detailed physical examination of the lesion, including size, shape, color, and surface features. The lesions are further examined using dermoscopy to observe the structural pattern and pigment distribution.
Spitz is a benign lesion that can be observed periodically if there are no obvious signs of discomfort; if there are changes or if the patient is concerned, laser treatment, cryotherapy or surgical excision may be considered. Patient management during treatment is equally important. Doctors should explain to patients in detail the nature of Spitz nevus, treatment options and possible risks and complications, and encourage patients to actively participate in the treatment process by asking questions and raising concerns.
Application of New Techniques in Diagnostic Dermoscopy
The use of dermoscopy in the diagnosis of Spitz nevi has provided new insights into the way nevi are observed morphologically and evolve. As technology evolves, high-resolution dermoscopy will be able to show skin structures more clearly and improve diagnostic accuracy. Combining artificial intelligence and machine learning algorithms to train models to identify and analyze specific features in dermoscopic images can assist physicians in making faster and more accurate diagnoses.
