Hobnail hemangioma reclassified as superficial lymphatic malformation: A study of 52 cases

Benign and low-grade superficial endothelial cell neoplasms in the molecular era

Vascular tumors are the most common mesenchymal neoplasms of the skin and subcutis, and they encompass a heterogeneous group with diverse clinical, histological, and molecular features, as well as biological behavior. Over the past two decades, molecular studies have enabled the identification of pathogenic recurrent genetic alterations that can be used as additional data points to support the correct classification of these lesions. The purpose of this review is to summarize the available data related to superficially located benign and low-grade vascular neoplasms and to highlight recent molecular advances with the role of surrogate immunohistochemistry to target pathogenic proteins as diagnostic biomarkers.

Curettage and sclerotherapy technique: A hybrid approach to superficial lymphatic malformation

OBJECTIVE

To describe the curettage and sclerotherapy technique, a hybrid approach to treatment for superficial lymphatic malformations.

METHODS

A retrospective analysis of a lymphatic malformation data base was performed. Patients with superficial lymphatic malformation treated by curettage and sclerotherapy technique with bleomycin were included in this study. Safety and efficacy of the curettage and sclerotherapy technique with bleomycin were evaluated.

RESULTS

Between September 2019 and October 2021, 10 consecutive patients (male/female ratio: 4:6; mean age, 10.9 years; range, 3-35 years) presented with superficial lymphatic malformations that were subsequently treated by curettage and sclerotherapy technique with bleomycin. All lesions were located on the trunk and extremities. Each patient received one treatment session and a mean follow-up of 12 months. We observed minor complications. No postoperative infections occurred in this series. No patient developed skin ulceration or necrosis. Scarring and recurrence occurred in one patient. Complete regression was confirmed for all 10 patients by photographic evaluation.

CONCLUSION

A curettage and sclerotherapy technique is proposed to treat superficial lymphatic malformation in this study. This technique seems to be safe and highly effective.

The contribution of Juan Rosai to the pathology of soft tissue tumors

The conceptual evolution in the field of soft tissue tumor pathology has been mostly driven by a relatively small group of individuals that includes giants of the past and the present such as James Ewing, Raffaele Lattes, Arthur Purdy Stout, Franz Enzinger, Sharon Weiss, Lennart Angervall, Harry Evans, Marku Miettinen, and Christopher Fletcher. Juan Rosai, not only exerted an immense impact on surgical pathology in general, but in consideration of his unique talent in identifying novel clinicopathologic entities, has also contributed remarkably to current understanding of mesenchymal neoplasms. The creation of desmoplastic small round cell tumor certainly ranks among his most relevant efforts, although he actually put his mark on a broad variety of soft tissue lesions, including vascular neoplasms. It would be impossible to include in a single article all the entities that he created or contributed to refine; therefore, this review is limited to a selection of what we believe represent true milestones.

Net-like superficial lymphatic malformation

The net-like superficial lymphatic malformation (LM) is a newly described entity with distinctive clinical, dermoscopic, and histologic characteristics. Clinical picture consists of red to purplish macules with a finely reticulated pattern of vascular structures. Dermoscopy shows arborizing telangiectatic vessels. Histology is characterized by a vascular proliferation composed of thin-walled vessels, located in the upper dermis, that stains positive with podoplanin (D2-40). We report a new case of LM with an additional clinical feature, hypopigmented areas.

Arborizing vessels in a targetoid hemosiderotic hemangioma: mistaken dermoscopic diagnosis of basal cell carcinoma

Targetoid hemosiderotic hemangioma (THH) or hobnail hemangioma (HH) is a benign vascular lesion that presents with the classical clinical presentation of a ring-shaped tumor having a targetoid appearance, with a central purple-brown papule surrounded by a thin pale area and an ecchymotic ring on the outside. Dermoscopic features and patterns of HH have been documented and have proven to be sufficient to establish a clinical diagnosis in many cases.

We present a facial lesion in which both the clinical presentation and dermoscopy were atypical. The presence of arborizing vessels in the dermoscopic pattern, never before described for this lesion, led us to the diagnosis of basocellular carcinoma (BCC). We also report the changes in this pattern experienced over 12 months of progression and their correlation with the histopathologic findings.

Hobnail Hemangioma With an Unusual Clinical Presentation

Hobnail hemangioma, also known as targetoid hemosiderotic hemangioma, is an uncommon vascular proliferation that clinically presents as a small solitary red to purple papule or macule, located on the limbs or trunk. Multiple lesions and atypical locations have been described. Histopathologically, it exhibits a biphasic pattern, with dilated vessels in the superficial dermis and angulated vessels in the deeper dermis, with endothelial cells that show a hobnail appearance. There is controversy about the histogenetic origin of hobnail hemangioma, although recent studies support that it is a lymphatic malformation. The investigators report the case of a 41-year-old man with an irregular lesion, red to purple in color, with a maximum diameter of 4 cm, on the scalp. The location and in particular the clinical appearance are uncommon. Immunohistochemical analysis showed negativity for WT1 and focal positivity for D2-40. Clinical-pathologic correlation acquires particular importance in the case of lesions with atypical clinical presentation.

Spitz Nevus Intermingling With a Hemangioma

We report on a Spitz nevus intermingling with a hemangioma in the same biopsy from the right thigh of a 10-year-old boy. The hemangioma was made of dilated vessels in superficial areas but of narrow and angulated vessels in the deep and lateral zones. The Spitz nevus was typical, showing maturation, and no worrisome cytological features. The immunohistochemical study demonstrated expression by the vascular component of CD31, CD34, factor VIII-related antigen, and Wilms tumor 1, whereas the vessels did not express D2-40 human herpes virus 8 or glucose transporter-1. The melanocytic component expressed HMB-45 (weakly and mainly in the superficial zones), Melan-A and S-100 protein. A perivascular continuous layer of pericytes expressing smooth muscle actin was also evident.

Hobnail Hemangioma (Superficial Hemosiderotic Lymphovascular Malformation) in Children: A Series of 6 Pediatric Cases and Review of the Literature

BACKGROUND

Hobnail hemangioma is a small benign vascular malformation of the superficial and mid-dermis with variable clinical presentation.

OBJECTIVES

To review the clinical characteristics of hobnail hemangioma in pediatric patients.

METHODS

A retrospective chart review performed of all histopathologically confirmed cases of hobnail hemangioma from May 2000 to December 2014. Data on demographics, clinical characteristics, and results of immunohistochemical staining were collected.

RESULTS

Four male and 2 female patients identified. Congenital lesions were reported in 3 cases. The most common anatomic location was the extremities. Treatment options included observation and surgical excision.

CONCLUSIONS

Hobnail hemangioma is an uncommon benign vascular malformation. Due to its benign nature, treatment is not required. If treatment is indicated, complete surgical excision appears to be the most effective option.

Dermoscopy of Targetoid Hemosiderotic Hemangioma: A Morphological Study of 35 Cases

BACKGROUND

Targetoid hemosiderotic hemangioma is an uncommon, vascular, benign solitary lesion of lymphatic origin that can be misdiagnosed as other tumors including melanomas.

OBJECTIVES

To evaluate the dermoscopic features of a large series of targetoid hemosiderotic hemangiomas.

METHODS

Digital dermoscopic images of 35 histopathologically confirmed cases of targetoid hemosiderotic hemangiomas collected from 7 hospitals in Spain and Italy were evaluated for the presence of dermoscopic structures and patterns.

RESULTS

The results of our study reveal that the presence of central red and dark lacunae and a peripheral circular reddish-violaceous homogeneous area is the most common dermoscopic pattern in targetoid hemosiderotic hemangioma (71.4%). The targetoid hemosiderotic hemangiomas of our study were correctly diagnosed in 77% of cases.

CONCLUSION

Dermoscopy is helpful in improving the diagnosis of targetoid hemosiderotic hemangioma. However, attention must be paid to those cases that dermoscopically may show nontargetoid patterns, which often mimic other lesions, including melanoma.

Immunohistochemistry in dermatopathology

CONTEXT

Immunohistochemistry is not a diagnostic test but a highly valuable tool that requires interpretation within a context.

OBJECTIVE

To review the current status and limitations of immunohistochemistry in dermatopathology.

DATA SOURCES

English-language literature published between 1980 and 2014.

CONCLUSIONS

Although immunohistochemistry is rarely completely specific or sensitive, it is an important adjunctive technique in dermatopathology and can be helpful in a series of diagnostic dilemmas.

Targetoid hemosiderotic hemangioma - Case report

Targetoid Hemosiderotic Hemangioma, also known as Hobnail Hemangioma, is a lesion of vascular origin, probably lymphatic. The most common clinical feature is a solitary violaceous papule surrounded by a pale, thin area and a peripheral ecchymotic ring, simulating a target. Histopathologically, there is a biphasic pattern, with dilated vessels in the superficial dermis and pseudoangiosarcomatous pattern in the deep dermis, and endothelial cells with hobnail morphology. A simple excision is curative. We report a rare case of Targetoid Hemosiderotic Hemangioma.

Cutaneous lymphatic malformation characterized by swelling of digits: a report of six cases

BACKGROUND

Cutaneous lymphatic malformations represent a group of heterogeneous diseases. In clinical practice, some cases of cutaneous lymphatic malformation have been found to differ from the well-characterized entities, and are difficult to classify.

OBJECTIVE

To report the clinical, histopathological and immunohistochemical characteristics of six cases of lymphatic malformation characterized by swelling of the digits.

METHODS

Six patients with swelling of the digits were included in this study. Histopathological examination and immunohistochemical staining of CD31, D2-40, Prox1, Wilms tumor 1 (WT-1) and human herpesvirus-8 (HHV-8) were performed for all cases.

RESULTS

All cases were congenital lesions and presented as swelling of single or multiple digits. Histopathologically, the lesions showed proliferation of small-to-medium-sized vessels in the dermis and subcutaneous tissue. These abnormal vessels were positive for CD31, D2-40 and Prox1, and negative for WT-1 and HHV-8.

CONCLUSION

The six cases reported herein represent a specific cutaneous lymphatic malformation different from previously reported entities.

Superficial hemosiderotic lymphovascular malformation (hobnail hemangioma): a report of six cases

Hobnail hemangioma (HH), initially termed targetoid hemosiderotic hemangioma, is a rare, often solitary lesion classically characterized by a central brown or violaceous papulonodule surrounded at times by an ecchymotic halo. This lesion is typically found on the trunk or limbs of children or young to middle-aged adults. Numerous case reports have found HHs to have a reproducible histologic appearance. Although the exact histogenesis of these lesions is unknown, multiple recent immunohistochemical studies suggest a lymphatic origin of these lesions. We present six cases of children with HHs with classic histology but with variability in their clinical appearance. Because the clinical presence of a targetoid halo is inconsistent and the hobnail phenomenon is not specific, we favor the designation of superficial hemosiderotic lymphovascular malformation instead of HH or targetoid hemosiderotic hemangioma as a more unifying term for this rare clinical entity. By eliminating confounding terminologies (in this case, incorporation of "hemangioma" in the name of this entity), we also hope to encourage a swifter change in practice to move away from erroneous diagnostic considerations.

Agminate lichen aureus

Lichen aureus is a rare variant of pigmented purpura, with a chronic and benign course. It is generally asymptomatic and often occurs in the lower limbs, presenting as erythematous brownish, coppery or golden macules and/or papules. The diagnosis is based on clinical and histopathological findings. The dermatoscopic pattern has been considered a useful tool in diagnosis presumption. We describe a case with a confluent morphological pattern, called agminate lichen aureus.

Benign lymphangioendothelioma: a clinical, histopathologic and immunohistochemical analysis of four cases

BACKGROUND

Benign lymphangioendothelioma represents a rare lymphatic vascular proliferation characterized by proliferation of irregular and thin-walled vessels dissecting amongst dermal collagen. Immunohistochemical analysis has been lacking in most previously reported cases.

METHODS

Herein, we report the clinical and histopathologic characteristics of four cases of benign lymphangioendothelioma. Immunohistochemical study was completed for all lesions.

RESULTS

All lesions presented as large, red to brown patches or plaques. Three lesions were located on the thigh and one lesion was located on the neck. Histopathologically, all lesions showed proliferation of anastomotic or retiform thin-walled vessels with a single layer of endothelial cells that dissect the dermis. D2-40 and Prox1 immunostains were positive and Wilms tumor 1 (WT-1) immunostain was negative in all cases.

CONCLUSION

Benign lymphangioendothelioma represents a lymphatic vascular proliferation. A lack of expression of WT-1 suggests it represents a lymphatic vascular malformation.

Solitary angiokeratoma on palms and soles: a clinicopathological analysis of 21 cases

Angiokeratoma includes a group of unrelated diseases characterized by hyperkeratosis and dilation of vessels in the superficial dermis. In this study, 21 cases of solitary lesions located on palms and soles and histopathologically diagnosed as angiokeratoma were analyzed retrospectively. All lesions presented as red to violet macules or plaques. Histopathologically, all of them showed hyperkeratosis and vascular dilation in the papillary to deep dermis. The elongated vessels were of different sizes and shape, lined by a single layer of endothelial cells. In 13 lesions, the endothelial cells protruded into the lumen, forming a hobnail appearance. Immunohistochemical study showed the endothelial cells were positive for CD31 and CD34, negative for D2-40, and focally positive for Wilms tumor 1 (WT-1) in most cases. Our cases represented a rare type of angiokeratoma located on the palms and soles, in which the focal positivity of WT-1 was different from previously reported vascular proliferations.

Hemangioendothelioma

Hemangioendothelioma is the term used to name those vascular neoplasms that show a borderline biological behavior, intermediate between entirely benign hemangiomas and highly malignant angiosarcomas. Although originally spindle cell hemangioendothelioma was proposed as a specific clinicopathologic variant of hemangioendothelioma, currently, it is considered as an entirely benign lesion, and thus, the name spindle cell hemangioma seems to be the most accurate for this lesion. Authentic hemangioendotheliomas involving the skin and soft tissues include papillary intralymphatic angioendothelioma (also known as Dabska tumor), retiform hemangioendothelioma, kaposiform hemangioendothelioma, epithelioid hemangioendothelioma, pseudomyogenic hemangioendothelioma (also known as epithelioid sarcoma-like hemangioendothelioma), and composite hemangioendothelioma. Each of these neoplasms exhibit characteristic histopathologic features. The most characteristic finding of papillary intralymphatic hemangioendothelioma consists of papillary tufts, with a central hyaline core lined by hobnail-like endothelial cells protruding into the lumina. Retiform hemangioendothelioma is an infiltrative neoplasm composed of elongated arborizing vessels, arranged in an anastomosing pattern that resembles that of the rete testis, and lined by a single layer of hobnail-like endothelial cells that protrude within the narrow lumina. Kaposiform hemangioendothelioma is composed of several solid poorly circumscribed nodules, and each nodule is composed of a mixture of small capillaries and solid lobules of endothelial cells arranged in a glomeruloid pattern. A frequent finding consists of the presence of areas of lymphangiomatosis adjacent to the solid nodules. Epithelioid hemangioendothelioma is composed of cords, strands, and solid aggregates of round, oval, and polygonal cells, with abundant pale eosinophilic cytoplasm, vesicular nuclei, and inconspicuous nucleoli, embedded in a fibromyxoid or sclerotic stroma. Many neoplastic cells exhibit prominent cytoplasmic vacuolization as an expression of primitive vascular differentiation. Pseudomyogenic hemangioendothelioma is a poorly circumscribed, fascicular lesion with infiltrative borders composed of round or oval neoplastic cells, with vesicular nuclei and inconspicuous nucleoli, and ample homogeneous eosinophilic cytoplasm, giving them a rhabdomyoblastic appearance. Finally, composite hemangioendothelioma is the term used to name locally aggressive vascular neoplasms of low-grade malignancy showing varying combinations of benign, low-grade malignant, and high-grade malignant vascular components. From the immunohistochemical point of view, proliferating cells of all hemangioendotheliomas express a lymphatic endothelial cell immunophenotype. Most hemangioendotheliomas are low-grade vascular neoplasms, with a tendency to recur locally and a low metastatic potential, mostly to regional lymph nodes. Epithelioid hemangioendothelioma, especially large lesions and those located in deep soft tissues, seems to have a more aggressive biological behavior.