Cutaneous ultrasound: key diagnostic tool for the relapse of a single eccrine spiradenoma.

Eccrine spiradenoma is a rare, benign, adnexal skin tumor of the sweat gland. It is frequently solitary and presents as a small lesion in the dermal or the subcutaneous fat layer. Eccrine spiradenomas rarely progress to malignant transformation but they can relapse. Due to its rarity, there have been few reports about the sonographic appearances of eccrine spiradenoma. Sonographic findings were reported in a relapsing case of an eccrine spiradenoma, located in the deep dermal layers and hypodermis of the preauricular region in a middle-aged man. Ultrasound was very useful to suspect the relapse. Histology was correlated with the sonography and discussed the previously reported imaging findings of eccrine spiradenoma and other sweat gland tumors.

Ultrasonographic features of eccrine spiradenoma: A case report.

RATIONALE: Eccrine spiradenoma (ES) is a rare benign skin adnexal tumor originating from eccrine sweat glands. The features of ES on ultrasonography (US) have received little attention. Therefore, we report the sonographic findings in a case of an ES that originated from the abdominal wall and discuss the previously reported cases. PATIENT CONCERNS: A 53-year-old woman was admitted to our hospital with a complaint of a painful nodule on the right side of her abdominal wall of 1-year duration. DIAGNOSES: The mass on the right side of abdominal wall was diagnosed as ES by histopathological examination. INTERVENTIONS: The patient subsequently underwent total excision of the mass. OUTCOMES: The patient recovered well and had no complications during the 1-year follow-up. LESSONS: As eccrine spiradenoma (ES) is rare and most of the tumors are excised without prior imaging studies. Little is known regarding the features of ES on ultrasonography (US). Familiarizing with the clinical and US features of this rare tumor may increase awareness of the disease among sonographers and clinicians.

Hidradenocarcinoma: a rare but challenging diagnosis.

Hidradenocarcinoma is a rare, aggressive cancer arising from sweat glands. Hidradenocarcinoma has no definitive histologic features compared to its benign hidradenoma, thereby posing a diagnostic challenge for clinicians and pathologists. This novel case report demonstrates specific MRI signs that suggested malignant degeneration of hidradenoma.

Solid-Cystic Hidradenoma: A Dorsal Foot Presentation.

Solid-cystic hidradenoma is a benign cutaneous tumor with eccrine sweat gland origins that is most commonly found in the head, neck, trunk, and upper extremity regions of patients in the middle to older age groups. These lesions are generally asymptomatic, slow-growing, solitary, and nonulcerative in presentation. Degenerative malignant transformation of this tumor is very rare. In this case report, the authors describe the marginal surgical excision and subsequent microscopic pathologic diagnosis of a moderate sized solid-cystic hidradenoma of the dorsolateral forefoot in a middle-aged male patient.

Dermoscopy of Adnexal Tumors.

Cutaneous adnexal tumors include lesions with apocrine, eccrine, follicular, sebaceous, and mixed differentiation. Most are benign and sporadic, although malignant forms are occasionally observed and some cases develop in the setting of inherited syndromes. These tumors often cause immense diagnostic difficulty. Dermoscopy is a noninvasive technique that has greatly improved the diagnostic accuracy of different skin lesions, including these tumors. We provide a review of the literature on the dermoscopic structures and patterns associated with adnexal tumors. Most patterns associated with this kind of tumor are nonspecific and are observed in other nonadnexal tumors, especially in basal cell carcinomas.

Clear Cell Hidradenoma: Characteristic Imaging Features on Ultrasonography, Computed Tomography, and Magnetic Resonance Imaging.

OBJECTIVES: The purpose of this study was to evaluate the imaging features of clear cell hidradenoma on ultrasonography (US), computed tomography (CT), and magnetic resonance imaging (MRI). METHODS: The radiologic and pathologic databases at 2 medical institutions were searched retrospectively from 2004 to 2016 to identify patients with a diagnosis of clear cell hidradenoma. Ultrasonographic, CT, and MRI features were described, and pathologic specimens were reviewed. RESULTS: There were 5 female and 4 male patients. The mean patient age was 48.9 years (range, 28-70 years). Five patients underwent only US; 2 patients underwent only CT; 1 patient underwent both US and CT; and 1 patient underwent US and MRI. Most of the tumors were located primarily in the subcutaneous fat layer. The mean tumor size was 18.4 mm. On US, 6 masses had a heterogeneous echo texture, including an anechoic portion with protruding echogenic portions. Two masses had multiple septa in the anechoic portion. On color Doppler US, blood flow was both central and peripheral in 5 patients. All 3 cases seen on CT presented as a low-attenuation mass with an enhanced solid internal nodule. On MRI, the mass showed heterogeneous signal intensity on T2-weighted images and enhancement of the peripheral wall and internal solid component on contrast-enhanced T1-weighted images. CONCLUSIONS: Clear cell hidradenoma is usually located in the subcutaneous fat layer, has a well-defined margin, appears as a cystic mass with an internal solid nodule, and occasionally has multiple septa on US, CT, and MRI.

18F-FDG PET/CT Imaging of Hidradenocarcinoma Arising From Preexisting Hidradenoma of the Knee.

Malignant tumors of the sweat glands are exceedingly rare and aggressive tumors. We present here a case of a 60-year-old man with a malignant hidradenocarcinoma that developed in a background of preexisting benign hidradenoma on the lateral aspect of the knee that was initially resected, but rapidly recurred with associated inguinal lymphadenopathy. F-FDG PET/CT was performed as part of preoperative staging, which demonstrated abnormal inguinal lymph nodes and metastatic disease to the lungs. FDG PET/CT can play an invaluable role in the initial staging and follow-up of this rare malignancy.

Sonographic Characteristics of Apocrine Nodular Hidradenoma of the Skin.

Nodular hidradenomas are benign sweat gland-derived tumors that can produce clinical and dermatoscopic misdiagnoses. Histologically, these tumors can be classified into eccrine and apocrine subtypes. We present the sonographic characteristics of 6 cases of apocrine nodular hidradenomas, which, to our knowledge, is so far the largest series reported. A detailed sonographic analysis included layers, body location, shape, diameters, echostructure patterns, and vascularity. Two sonographic signs not previously reported in these or other common dermatologic lesions were detected: "snow falling" and "fluid-fluid level." The sonographic characteristics of apocrine nodular hidradenomas can support their earlier and more precise diagnosis.

Dermoscopy of Skin Adnexal Neoplasms:A Continuous Challenge.

Dear Editor, Apocrine hidradenoma is a rare benign adnexal tumor related to the more common poroma, as they both originate from sweat glands. Hidradenoma usually has an eccrine differentiation, but an apocrine differentiation is possible. Due to its rarity and non-specific clinical appearance it is difficult to differentiate it from other malignant cutaneous lesions. In this challenging task, dermatoscopy could be particularly helpful to better describe, recognize, and differentiate these lesions. Unfortunately, the literature offers only few dermatoscopic descriptions of this rare cutaneous neoplasm. A 70-year-old woman in fair general condition was referred to our Department for an asymptomatic 10×8 mm single nodule on her left scapula. This nodule was red, dome shaped, well circumscribed, firm, and mildly tender (Figure 1). The patient reported that it had been present since approximately 7 months. The lesion was neither painful nor itchy and there was no bleeding. A skin examination did not show any other lesions with the same features or other suspicious lesions. Dermatoscopy revealed milky-pinkish areas with dotted vessels, linear-irregular vessels, and hairpin vessels: some of these aspects can also be found in amelanotic melanoma (1). There were also homogeneous blue areas similar to lacunae, characteristic but not exclusive to vascular or sarcomatous neoplasms and basal cell carcinoma (1,2). Furthermore, small ulcerations covered by an amber crust were identified, which can usually be found in basal cell carcinoma. Regarding the background of the lesion, we noticed peculiar, translucent, pinkish, soft, large lobular areas (Figure 2). On the basis of this analysis, we suspected an atypical presentation of a basal cell carcinoma, an amelanotic melanoma, or a sarcomatous skin neoplasm. A metastasis of an unknown solid tumor was also taken into consideration. The histological examination revealed an adnexal neoplasm and specifically an apocrine hidradenoma. The neoplasm had variably sized nests and nodules of neoplastic epithelial cells, with a small ductular lumens confined within the upper dermis. The lesion was composed mainly of two cell types: polygonal and smaller, elongated, and darker cells. The cuboidal/polygonal cells were seen lining the duct-like spaces and slots and resembled those of poroma (Figure 3). The adnexal skin tumors group includes a complex variety of uncommon tumors that can be distinguished only histologically, and most of them are benign (3). Searching the literature for "hidradenoma dermoscopy" and "adnexal dermoscopy" yields multiple descriptions of poromas but few dermatoscopic descriptions of hidradenoma (4). There was only one report of the presence of "arborizing vessels"(5), and another described "reddish purple areas and some linear or hairpin-like vessels on the surface of the tumor" (6). In another paper we found: "irregular scar like whitish areas and a polymorphous vascular pattern including irregular reddish-purple areas mimicking lacunar appearance of hemangiomas with thick hairpin vessels at the periphery" (7). It is very difficult make use of such scant data especially in order to detect a leading pattern for a specific diagnosis. Moreover, the described structures lack in specificity, being also present in many other lesions. Analyzing our dermatoscopic image and comparing it to the other ones available in the literature, we identified a peculiar background. It consisted in the presence of multilobular translucent and pinkish soft areas, which fit the previously described dermatoscopic criteria. We hypothesize there is a correlation between this feature and the histopathological presentation with variably sized nests and nodules. Of course, further case reports of hidradenoma are needed to identify the soft lobular background as a distinctive dermatoscopic feature. Due to the lack of specific features both clinically than dermatoscopically, histopathological analysis remains the only gold standard for diagnosis of these benign mimicking lesions.

Managing a Rare Malignant Sweat Gland Tumor Invading the Brain: Case Report and Literature Review.

BACKGROUND: Malignant sweat gland adnexal tumors are rare with an incidence of 0.001%. Of these, clear cell hidradenocarcinoma is an extremely uncommon subtype that accounts for 6% of malignant eccrine sweat gland tumors. They occur commonly in the head, neck, and extremities. Although they have a propensity for local recurrence, intracranial extension with brain invasion is extremely rare. CASE DESCRIPTION: We report a 76-year-old man with a large, recurring, ulcerated, fungating scalp swelling of 14 years who presented with focal seizures and drowsiness. Neuroimaging revealed a massive tumor arising from the scalp to invade the left parietal lobe and extending to the right side with occlusion of the superior sagittal sinus. The overlying parietal bone was lytic with a "moth-eaten" appearance. He underwent wide excision of the scalp lesion, near-total cerebral tumor decompression followed by titanium mesh cranioplasty, rotation flap reconstruction of the scalp, and adjuvant radiotherapy to the skull vault. Histopathology revealed clear cell hidradenocarcinoma. Whole-body positron emission tomography scan did not reveal any other lesion. At 24 months' follow-up, he remains recurrence free. CONCLUSION: We report a rare indolent case of clear cell hidradenocarcinoma invading the brain, which was managed with near-total decompression and adjuvant radiotherapy. Intracranial extension in such aggressive tumors poses challenges in management, and regular neuroimaging surveillance is advised.

Dermoscopy of Nodular Hidradenoma, a Great Masquerader: A Morphological Study of 28 Cases.

BACKGROUND: Nodular hidradenoma is an uncommon, benign, adnexal neoplasm of apocrine origin which is a clinical simulator of other tumours. OBJECTIVE: The aim of this study was to evaluate the morphological findings of a large series of nodular hidradenomas under dermoscopic observation. METHODS: Dermoscopic examination of 28 cases of nodular hidradenomas was performed to evaluate specific dermoscopic criteria and patterns. RESULTS: The most frequently occurring dermoscopic features were: (1) in 96.4% of cases, a homogeneous area that covered the lesion partially or totally, the colour of which was pinkish in 46.4% of cases, bluish in 28.6%, red-blue in 14.3%, and brownish in 10.7%; (2) white structures were found in 89.3% of cases; (3) in 82.1% of cases, vascular structures were also observed, especially arborising telangiectasias (39.3%) and polymorphous atypical vessels (28.6%). CONCLUSION: Nodular hidradenomas represent a dermoscopic pitfall, being difficult to differentiate clinically and dermoscopically from basal cell carcinomas and melanomas.

Hidradenoma of the external auditory canal: clinical presentation and surgical treatment.

The aim of this article is to present clinical features, diagnostic procedures and surgical treatment of a rare ear tumor. We report a case of 78 year old female with hidradenoma of the external auditory canal. Patient had a sensation of pain and fullness with permanent ottorhea from the right ear for one year Temporal bone computed tomography showed a tumor of the external ear, 6 centimeters in diameter, without bone, temporomandibular joint or intracranial invasion; the tumor was limited medially by the tympanic membrane. Biopsy was performed and pathohistology finding was: hydradenoma nodulare atypicum. Surgical intervention and wide tumor removal in general endotracheal anesthesia was performed. One year after the surgery there was no sign of tumor recurrence. Hidradenoma is rare ear tumor arising from the epithelial cells of sweat glands of the external auditory canal. Radiological evaluation and pathohistology confirmation of hidradenoma is necessary and wide excision of the tumor is the treatment of choice.