Benign and malignant collision tumors of melanocytic skin lesions with hemangioma: Dermoscopic and reflectance confocal microscopy features

[Collision tumours in skin: usually an incidental finding. A retrospective study with literature revision]

A collision tumour (CT) is a neoplastic lesion comprised of two or more distinct cell populations that maintain distinct borders. Mostly, these are incidental findings in skin biopsies, whose pathologic mechanism and prevalence remain unknown, with few references among literature. Here, we present a retrospective study of CT, diagnosed by a dermatopathologist in our hospital between 2019-2022. Lesions have been defined individually and organized into three categories: benign-benign (BB), benign-malignant (BM) and malignant-malignant (MM). A total of 108 CT were diagnosed (1,4% of the biopsies from the dermatopathologist during this period), from which BM was the most frequent collision (48,5%). Globally, basal cell carcinoma (BCC) was the main malignant lesion and melanocytic nevus (MN) the main benign lesion. We have used the software Stata 14.2 in order to analyse results, and we have detected a statistically significant difference between age and collision type.

De Novo Glioblastoma Masqueraded within a Hemispheric Dural Meningiomatosis: Rare Imaging Findings and Rationale for Two-Staged Resection

Introduction  Collision tumors present as histologically different juxtaposed neoplasms within the same anatomical region, independent of the adjacent cell population. De novo intracranial collision tumors involving metachronous primary brain neoplasms alongside dural meningiomatosis are not well documented in the literature.

Clinical Presentation  We present staged surgical management of a 72-year-old female with known left hemispheric stable dural-based convexity mass lesions over 10 years and new-onset expressive aphasia and headaches. MRI had revealed left supratentorial dural-based enhanced masses consistent with en plaque meningiomatosis. Embolization angiography showed an unusual tumor blush from an aberrant branch of anterior cerebral artery suggesting a deeper focal intra-axial nature; a stage 1 craniotomy for dural-based tumor resection was completed with diagnosis of a meningioma (WHO grade 1). Intraoperatively, a distinct intra-axial deep discrete lesion was verified stereotactically, concordant with the location of tumor blush. The patient made a complete neurological recovery from a transient postoperative supplemental motor area syndrome in a week. Subsequent postoperative follow-up showed worsening of right hemiparesis and MRI showed an increase in residual lesion size and perilesional edema, which prompted a stage 2 radical resection of a glioblastoma, WHO grade 4. She improved neurologically after surgery with steroids and physical therapy. At 15 months following adjuvant therapy, she remains neurologically intact throughout the postoperative course, with no recurrent tumor on MRI.

Conclusion  A de novo glioblastoma presented as a masquerading lesion within hemispheric convexity meningiomatosis in an elderly patient with no prior radiation/phakomatosis, inciting a non-causal juxtapositional coexistence. The authors highlight rare pathognomonic angiographic findings and the rationale for two-staged resections of these collision lesions that led to excellent clinicoradiological outcome.

Clinical-Dermoscopic-Histopathological Correlations in Collision Skin Tumours

Objectives

Collision tumours are rare situations characterised by the coincidence of two different skin neoplasms in the same lesion.

Methods

We have analyzed 41 collision skin tumours from one department in the clinical-dermoscopic-histopathologic correlations.

Results

We present 41 collisions tumours. The mean age of our patients was 67.9 years, the mean diameter of the lesion was 11.6 mm. The most frequent locations were trunk (27 lesions) and head/neck (11 lesions). The collisions were classified as benign/benign (13 cases), benign/malignant (25 cases) and malignant/malignant (3 cases). The most frequent participants were seborrheic keratosis (24 cases), malignant melanoma (17 cases), melanocytic nevus (14 cases), basal cell carcinoma (12 cases) and heamangioma (10 cases). Thirty cases were of "dominant/minor" type and 11 cases of "half to half" type. Malignant tumours were a part of 28 collisions; these lesions were larger, patients were older and the malignant part was dominant in most cases. More than half of the collisions were unexpected by the initial clinical examination. Six collisions were missed by the initial histopathological examination.

Conclusions

Collision tumours can be missed by clinical or even histopathological examination. Dermoscopy is very helpful in the recognizing of difficult cases and cooperating with the histopathologist.

Dermoscopy of early melanomas: variation according to the anatomic site

To date, is yet to be elucidated whether the body location of cutaneous melanoma can significantly affect an early dermoscopic diagnosis and, consequently, if it can be regarded as a prognostic factor. To investigate the dermoscopic appearance of early melanomas (EMs) at different body sites; to test the ability of dermoscopists in recognizing specific dermoscopic features in EMs. A pool of 106 experienced dermoscopists evaluated the presence of 10 dermoscopic features assumed as suggestive of malignancy among 268 images of EMs with ambiguous appearance located at 16 body sites. According to 720 evaluations, EMs of the "upper extremities" showed a prevalence of early atypical lentiginous features. EMs of the "anterior trunk" exhibited the lower rate of recognition for all features. EMs of the "rear trunk" can be regarded as an intermediate area, showing high recognition rates of regression-related and chronic-traumatism-related features.

A new clinical and dermoscopic monitoring of infantile hemangiomas treated with oral propranolol

Oral propranolol (OP) demonstrated high efficacy and safety profile for treatment of critical infantile hemangiomas (IHs). Our aim was to assess the morphologic changes of IHs with standard and high-resolution video dermoscopy (HRVD) from baseline to 18 months either in presence or absence of OP therapy; to investigate if extended anamnestic perinatal data and clinical-dermoscopic characteristics of the IHs can correlate with therapeutic outcome. We enrolled 94 patients (112 IHs): 58 were treated with OP, 35 (42 IHs) for 6 months (group 1), and 23 (25 IHs) for 12-months (group 2); 36 (45 IHs) were followed-up. Clinical-dermoscopic examinations were performed every 3 months during therapy and follow-up. Among 67 treated IHs, superficial and deep IHs with homogenous clinical-dermoscopic aspect developed after the 2 weeks of life achieved the better outcome, stable at 9-month follow-up, independently form treatment duration. Under HRVD, glomerular vessels were prevalent at baseline; corckscrew, comma, and linear-irregular vessels were the prevalent pattern at 1, 3, and 6 months of therapy, respectively. At 12-month follow-up, adequate healing was achieved by 96% of IHs in group 2 and by 78% in group 1, showing dotted vessels. Persistent IHs displayed a reticulated aspect and linear irregular vessels, while arborizing vessels characterized relapsed IHs. A 12-month OP therapy can be considered for newborns presenting with nonhomogenous mixed IHs >3 cm on the perineal area/lower extremities. In conclusion, HRVD allows a real time monitoring of vascular changes in IHs treated with OP and can support physicians in identifying relapses before they become clinically evident.