Trichoblastoma: is a clinical or dermoscopic diagnosis possible?

Adnexal neoplasms of the eye

Adnexal neoplasms of the eyelid encompass a wide variety of benign and malignant tumors of sebaceous, follicular, and sweat gland origin. Due to the specialized structures of the eyelid, these neoplasms present differently when compared with those of other locations. Although most dermatologists and ophthalmologists are familiar with the commonly reported adnexal tumors of the eyelid, such as hidrocystoma, pilomatrixoma, and sebaceous carcinoma, many other adnexal neoplasms have been reported at this unique anatomic site. Accurate and timely identification of these neoplasms is essential, as alterations of eyelid anatomy and function can have a negative impact on eye health, vision, and quality of life. We review the clinical and histopathologic features of common and rare eyelid adnexal neoplasms and discuss proposed treatment options.

A suspicious mole under the knee

This clinicopathological case describes a rare type of pigmented skin lesion. Pigmented trichoblastomas constitute an extremely rare type of benign primary neoplasm of the skin that can clinically resemble more common malignant neoplasms but present characteristic histological features.

Nevus Sebaceous of Jadassohn in Adults-Can Reflectance Confocal Microscopy Detect Malignant Transformation?

Nevus sebaceous of Jadassohn (NSJ) is a rare congenital lesion that affects the adnexal structures of the skin. It is typically located on the scalp and face of females and presents as a well-defined, slightly elevated, yellow lesion. It is also linked to a high risk of secondary tumors, which are more frequently benign than malignant. In vivo reflectance confocal microscopy (RCM) is a non-invasive imaging technique that provides a horizontal image of the skin with a resolution similar to histology. We report a case of basal cell carcinoma (BCC) developed in an NSJ with its dermoscopic, confocal, and histopathological features. A 49-year-old female presented with a well-circumscribed, 1 cm-diameter verrucous, yellowish lesion surrounded by a poorly defined, slightly erythematous, translucent plaque, located on the scalp in the temporoparietal region, which had been present since birth, grew at puberty, and changed its appearance in the last three years. Dermoscopy of the central lesion revealed yellow globules grouped into clusters, with peripheral linear and arborescent thin vessels, surrounded by several translucent nodular lesions with fine, arborizing vessels. RCM examination showed large, monomorphic cells with a hyperreflective periphery and a hyperreflective center located on the central lesion, corresponding to sebocytes, surrounded by multiple dark silhouettes lined with hyperreflective bands of thickened collagen, corresponding to tumor islands. The histopathological findings confirmed the diagnosis of BCC developed on an NJS. RCM can be a useful technique for the non-invasive examination and monitoring of these lesions, taking into account their transformation risk and preventing unnecessary excisions that might have a detrimental aesthetic impact on patients.

Trichoepithelioma on the Finger: A Rare Location and Dermoscopic-Histopathologic Correlation

ABSTRACT

Trichoepithelioma is a benign adnexal neoplasm of follicular germinative cells, with bulbs, papillae, and sheaths of perifollicular connective tissue as signs of follicular differentiation. Accordingly, trichoepithelioma may arise in any hair-bearing location, mostly on the face. That is why trichoepithelioma cannot appear in glabrous skin, and, although the dorsum of the hands and feet are a hair-bearing area, acral location is exceptional. We report the first case of trichoepithelioma localized in the finger of a 79-year-old man. It was a brown-pink, firm, 7-mm diameter, solid papule on the dorsal aspect of his left index finger. The lesion was completely asymptomatic, and he remembered to have it for many years. We describe this case highlighting its rare anatomical location and correlate its dermoscopic features with the histopathological appearance.

Significance of Dermoscopy in Association with Clinical Features in Differentiation of Basal Cell Carcinoma and Benign Trichoblastic Tumours

Background: Although basal cell carcinoma (BCC) can, in the majority of cases, be diagnosed based on clinical and dermoscopic assessment, a potential overlap with benign adnexal skin tumours seems to exist, including trichoblastic tumours (TT). Methods: Retrospective analysis of clinical and dermoscopic features of benign TT and BCC cases was performed to develop a diagnostic algorithm with a potential utility in clinical practice. Results: In the study, 502 histopathologically confirmed BCC cases were compared with 61 TT (including 44 TB (72.13%), 10 TE (16.39%) and 7 DTE (11.48%]). Patients in the BCC group were statistically older (mean age was 71.4 vs. 64.4 years, respectively; p = 0.009). BCC presented generally as larger tumours (mean tumour size 11.0 vs. 8.2 mm for the TT group; p = 0.001) and was more frequently associated with clinically visible ulceration (59.4% vs. 19.7%, respectively; p < 0.001). Comparison of lesion morphology, clinically visible pigmentation, and anatomical location did not show significant differences between the analysed groups. Dermoscopically visible ulceration was significantly more common in the BCC group compared to the TT group (52.2% vs. 14.8%; p < 0.0001). Pigmented structures, specifically brown dots and brown globules, were significantly more prevalent in the TT group (32.8% vs. 11.4%; p = 0.0001 and 29.5% vs. 8.2%; p <0.0001). Similarly, TT more commonly than BCC showed the presence of cloudy/starry milia-like cysts (26.2% vs. 11.6%; p = 0.0031) and yellow globules (16.4% vs. 7.2%; p = 0.033). Conclusions: Despite differences in frequency of clinical and dermoscopic features between BCC and TT in the studied group, differential diagnosis based on these variables is not reliable. Histopathological examination remains a diagnostic gold standard in differentiation of BCC and TT.

Trichoblastoma mimicking basal cell carcinoma and the approach to its management: Case report

INTRODUCTION AND IMPORTANCE

Trichoblastoma is a benign and rare cutaneous lesion with striking resemblance to basal cell carcinoma. However, the course of the illness varies significantly from basal cell carcinoma. It usually takes a less malicious route and causes minimal harm to the patient,unlike basal cell carcinoma where it can be aggressive and requires additional radiotherapy. Therefore, being able to differentiate them from one another is crucial to properly set a management plan.

CASE PRESENTATION

A 44-year-old Saudi male, diagnosed with basal cell carcinoma of the scalp in Dammam Medical Centre (DMC) and was referred to our hospital for re-excision of positive margins. Slide review of the histopathology samples in our hospital showed features consistent with trichoblastoma. This was further confirmed by a dermahistopathologist.

CLINICAL DISCUSSION

This rare benign tumour has posed multiple challenges in the clinical setting as not enough studies were conducted in order to dictate a proper management course. However, current management approach to the majority of skin lesions rely on the histopathological subtype and surgical excision. Many benign and malignant dermatological entities may mimic basal cell carcinoma, and therefore misdiagnosis can lead to either unnecessary excision or delayed treatment of metastatic disease. It is important to request the proper investigations to ease the process of diagnosis and more importantly, the process of differentiation.

CONCLUSION

Differentiating the two tumours from one another allows for the initiation of proper treatment early resulting in an improved prognosis for both lesions. The gold standard investigation to diagnose and differentiate between them is a surgical biopsy. Trichoblastoma typically has a favourable prognosis with a low incidence of recurrence or progression.

The Multiple Faces of Nodular Trichoblastoma: Review of the Literature with Case Presentation

Trichoblastoma (TB) is a rare biphasic benign adnexal neoplasm originating from follicular germ cells but clinically, it can simulate basal cell carcinoma (BCC), making the diagnosis more difficult. There are several variants of Trichoblastoma and a good knowledge of these is essential for correct diagnosis and management. We report two new cases observed in the last year at our Pathological Anatomy Operative Unit, and conduct a careful review of the literature, from the first description of this lesion by Headington in 1970 to the most recent classifications.

Clinicopathologic analysis of trichoblastoma and comparison with nodular basal cell carcinoma

BACKGROUND

Trichoblastoma (TB) is an uncommon benign follicular tumour for which clinical data is limited since most reports originate from pathology studies.

OBJECTIVE

To describe the clinical aspects of TB.

METHODS

This is an ancillary study of a prospective multicentre cohort of 2710 clinically suspected basal cell carcinoma (BCC), including 935 nodular BCCs. Sixty-two cases were TB: they were analysed and compared to 935 nodular BCCs.

RESULTS

TB mostly occurred in females (61% vs. 43% for BCC, P<0.01) of mean age 63 years. They were located on the head and neck, mainly on the nose and forehead, in 87% of cases. The mean size was 8.1mm, 77% were<10mm (55% of BCCs, P<0.001), 8% were ulcerated (vs. 21% of BCCs, P<0.02), and 47% persisted for more than 1 year (34% of BCCs, P<0.05). Most cases had a clinical presentation similar to nodular BCC, except for 5 small, flat, white papules and 1 anfractuous plaque.

LIMITATIONS

Cases originated from a series of tumours clinically suspected as BCCs.

DISCUSSION

Some 2.6% of tumours clinically diagnosed as BCC are in fact TB. TB occurs on the head, are more frequent in women, and are smaller and of longer duration than BCC. In most cases, clinical diagnosis on clinical grounds is difficult.

Extensive Facial Trichoblastoma - A Rare and Disfiguring Condition

Patient: Female, 62-year-old

Final Diagnosis: Trichoblastoma

Symptoms: Nodular skin lesion • papular skin lesion

Medication: —

Clinical Procedure: —

Specialty: Dermatology • Family Medicine • Plastic Surgery

Trichoblastomas Mimicking Basal Cell Carcinoma: The Importance of Identification and Differentiation

Trichoblastoma is a rare, slow-growing, benign cutaneous tumor derived from follicular germinative cells. Trichoblastoma commonly appears as an asymptomatic, symmetrical, well-circumscribed, skin-colored to brown or blue-black papule or nodule. It may appear clinically and histologically similar to basal cell carcinoma, making its diagnosis challenging. Even on dermoscopy, it is challenging to differentiate trichoblastoma from basal cell carcinoma. In practice, it is important to differentiate the two, because the choice of treatment and resulting prognosis differ between the lesions. Surgical biopsy to analyze histopathological and immunohistochemical differences is the gold standard for diagnosing and differentiating trichoblastoma from basal cell carcinoma. Trichoblastoma typically has a favorable prognosis, with a low incidence of recurrence, progression or association with malignancy. This paper provides a review of the epidemiology, clinical presentation, dermoscopy, histology, immunochemistry, treatment, and prognosis of trichoblastoma.

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.

[Why is it important to differentiate trichoblastic carcinomas (CT) from basal cell carcinomas (CBC). About 21 cases]

Trichoblastic carcinoma is a rare epithelial malignant epithelial tumor, its diagnosis is difficult and the therapeutic management is non-consensual. This retrospective study, carried out between 2009 and 2015, covered 21 cases and analyzed the diagnostic and therapeutic characteristics of trichoblastic carcinomas. Sex ratio is 2. Trichoblastic carcinoma predominated in the face (65% of cases), particularly in perinasal (30% of cases). Its clinical presentation is in 95% of cases as basal cell carcinoma, which is the first clinical diagnosis evoked. The average size of the tumors was 2.3cm in diameter (from 0.7cm to 15cm). The treatment of these tumors is surgical: the margins retained were on average 0.7cm (0.5cm to 1cm). The first excision was mostly performed under local anesthesia, healthy borders were found in less than 40% of cases, requiring another intervention under general anesthesia with reconstruction by flap or skin graft in nearly 80% of cases. The lymph node metastasis rate was 5%. Three cases of recurrence (17%) occurred between 18 months and 6 years follow-up, despite complete resection. One case recurred three times. These results highlight the difficulty of diagnosing trichoblastic carcinomas, often confused with basal cell carcinomas. Though larger, poorly limited and infiltrating, trichoblastic carcinomas are not really distinguished from basal cell carcinomas. Only the anatomopathological examination of the excision piece make it possible to conclude, the biopsy being most often insufficient. Their local aggressiveness requires a greater margin of excision. The micrographic analysis of Mohs, for the periorificial lesions of the face, would reduce margins, increase their reliability and limit the number of surgical revisions. Finally, the literature reports a high rate of ganglion and visceral metastases (between 9.5 and 11%). Initial search for distal lymph node or metastatic involvement is essential, as well as regular clinical follow-up.