Synchronous giant pilomatrixoma and Warthin tumour in the head and neck region

Introduction

Pilomatricoma, also known as calcifying epithelioma of Malherbe, is a benign tumour originating from the hair matrix cells, typically measuring 1–5 cm in size [1]. Pilomatricoma can occur in any area of hairy skin, but it most commonly, approximately in 64%, affects the head and neck [1]. Preoperatively, it is difficult to diagnose, with correct diagnosis established only in 16% of cases [2]. Treatment involves radical excision of the lesion with its capsule, leading to complete cure [1].
Warthin’s tumour (WT) also known as papillary cystadenoma lymphomatosum is the second most common benign tumour of the parotid gland with male predominance [3]. It occurs typically in the inferior pole of the parotid gland unilaterally, but 10% of cases are bilateral [3].

Aim

The aim of this study is to present the patient with a rare condition of two synchronous tumours: giant pilomatrixoma in the submandibular region and Warthin tumour in the parotid gland. In the literature we have not found any described case of synchronously occurring WT and pilomatricoma, thus we aimed to draw the attention of otorynolaryngologists to the multiple tumours. We also want to point out the need of the differential diagnosis of lesions occurring in the head and neck area with pilomatricoma.

Case report

A 57-year-old male with a mass in the midline of the neck measuring 11x6x4 cm is presented (Figures 1 A–C). The patient noticed the lesion approximately 4 years before the surgery was made, and it was rapidly increasing in size over the past 2 years. He did not pay attention to the mass in the preauricular region. The man’s job involves repairing refrigeration equipment and as a result he is exposed to various chemicals. He has a history of type II diabetes mellitus, hypertension, and hypothyroidism. Past medical history includes smoking for many years and the frequent use of a mobile phone.
The patient visited a doctor approximately 3 years ago, and a contrast-enhanced neck computed tomography (CT) revealed a soft tissue structure measuring 3.0 × 5.8 × 3.5 cm in the midline of the neck within the subcutaneous tissue. Additionally, a focal lesion measuring 2.2 cm with fluid-filled spaces was visible in the lower pole of the left parotid gland. Multifocal WTs were suspected at that time, but the patient discontinued further diagnostics and treatment.
Due to rapid tumour growth over 2 years, the patient decided to seek medical attention again. In January 2024, a repeat contrast-enhanced neck CT was performed in the outpatient setting. The findings were as follows: a well-defined soft tissue change with calcifications measuring 74 × 50 × 49 mm in the midline of the neck within the subcutaneous tissue. Furthermore, progression in the size of the focal lesion in the lower pole of the left parotid gland to 24 × 28 × 37 mm.
On 30 January 2024, the patient underwent the first surgical procedure in the Otolaryngology Department in Wroclaw, during which the lesion in the midline of the neck was removed (Figures 2 A, B). No infiltration of the laryngeal cartilage, hyoid bone, or thyroid cartilage was observed during the procedure. Histopathological examination revealed pilomatricoma.
Three months later, the patient was admitted to the Otolaryngology Department for planned removal of the lesion in the left parotid gland (Figures 3, 4). On 12 March 2024, under general anaesthesia with endotracheal intubation, the tumour in the lower pole of the left parotid gland was dissected. Histopathological examination confirmed a WT. The surgery proceeded without complications. The patient is under the care of the laryngology department.

Discussion

Pilomatrixoma or pilomatricoma manifests as a benign solid neoplasm originating from the hair follicle matrix. It was first described by Malherbe and Chenantais in 1880 [4]. The present terminology was established by Forbis and Helwig in 1961 [5]. Typically, it appears in the craniofacial region, cervical region, and upper limbs during the first two decades of life [6, 7]. Lesions commonly vary in dimensions from 0.5 cm to 3.0 cm. If the lesion is larger than 5 cm in diameter, it is described as a giant pilomatrixoma. Based on literature findings, there appears to be a higher prevalence of giant pilomatrixoma in adult males, particularly in regions of the upper limb, followed by the parotid region and the back [6]. Numerous giant pilomatrixomas have been reported, however the largest documented giant pilomatrixoma measured 34 cm × 21 cm × 17 cm in a 17-year-old boy [6, 8, 9].
Misdiagnosing a pilomatrixoma as a salivary gland tumour is a common mistake made by otolaryngologists. Confirming the accurate diagnosis may be difficult when it presents in the region of the salivary glands. Numerous cases of misinterpretation have been described, not only in clinical examinations but also in fine needle aspiration cytology (FNAC) diagnostics [10–12].
In our work, we present the patient in whom we suspected multifocality of WT. Only histopathological examination allowed us to establish the final diagnosis.
TWs are of lymphoid origin, and can occur bilaterally, but also have a tendency to multifocality and their predisposition to the occurrence is smoking tobacco to which the patient was exposed. The literature reported that in about 12% of patients, TW develops in more than one location [13].
As we have shown, pilomatrixoma can occur simultaneously with salivary tumours; so far we have not been able to get to the literature that described the coincidence of this tumour with WT while one of the articles presented the case of a patient with the current pilomatrixoma and a pleomorphic adenoma tumour within one parotid gland [12]. Both tumours were completely cut out leading to the patient’s cure.
Pilomatricoma, a rare skin tumour, can be clinically mistaken with salivary gland tumours. As demonstrated in our case, it occurred simultaneously with a parotid WT, what strongly suggested the multifocal TW development. It is imperative to draw the attention of otolaryngologists to differentiate lesions in the head and neck region with pilomatricoma.

Funding

No external funding.

Ethical approval

Not applicable.

Conflict of interest

The authors declare no conflict of interest.

References