Multiple Pyogenic Granulomas in the External Auditory Canal

Introduction

Pyogenic granuloma (PG), or lobular capillary hemangioma, is a benign vascular tumor of the skin or mucous membranes. It occurs at any age, with a peak incidence in the second and third decades of life. ¹ Moreover, it can occur in any part of the body, but one-third of PGs were reported in the head and neck region, especially on the cheek, lip, and oral cavity. Although PG is commonly found in the head and neck regions, it rarely presents in the external auditory canal (EAC). This is the first report of multiple PGs in the EAC of a 36-year-old man.

Case Report

A 36-year-old man presented with a mass in the left ear. The mass had been present for at least 2 years, but he could not recall when it appeared and whether its size changed. He had no history of trauma or insect bites and denied using cotton buds; however, he often rubbed his ear. He did not complain of hearing loss or ear fullness, and the mass was painless when manipulated. Physical examination revealed 2 masses in the left cartilaginous EAC. The one located laterally was .6 cm × .6 cm in size, and the other one was .3 cm × .3 cm. Both lesions were firm, smooth-lined, and erythematous. No bleeding or pain occurred during manipulation (Figure 1A). Imaging studies were limited due to the small size of the masses; however, they revealed highly enhancing masses confined to the superficial layers without adjacent bony erosions (Figures 1B).OPEN IN VIEWER

Surgical removal was planned, and the lesions were excised down to the perichondrium under local anesthesia (Figure 2A). The larger defect was sutured to achieve primary closure, and the smaller defect was left to heal by secondary intention. Histological examination revealed small capillary-sized blood vessels confined to the subcutis (Figure 2B). They were infiltrated by chronic inflammatory cells consisting of plasma cells, eosinophils, and lymphocytes (Figure 2C). These findings are consistent with the diagnosis of PG. Postoperative follow-up after 8 weeks revealed uneventful healing.OPEN IN VIEWER

Discussion

To our knowledge, this is the first report of multiple PGs in the EAC. PGs are rarely present in the EAC, and less than 10 cases have been reported since 1989 (Table 1). PGs are mostly present in solitary form; however, there have been a few case reports of multiple forms in other parts of the body. Multiple PGs can occur in 2 clinical variants: 1) satellite lesions around a primary lesion and 2) the disseminated form. Satellite lesions develop after damage to the primary lesion, usually after excision. They may appear either alone or in association with recurrence of the original lesion. ² Disseminated lesions are rare. They mostly occur after trauma, such as burns^3,4 or systemic drug administration, ⁵ and very rarely, they can spontaneously develop in children as a syndromic form. ⁶ The present case is unique as the PGs appeared in multiple forms even without any trauma, as long as the patient could recall.

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Table 1.

Reported Pyogenic Granuloma in the External Auditory Canal.

Authors (year)	Sex	Age	Size (mm)	Causes	Development Period	Treatment	Follow-up
Huang et al. (2020) 7	F	34	ND	Nail scratch	5 days	Excision	ND
Dick et al. (2016) 8	F	29	14	After childbirth	8 weeks	Excision	16 months
Courtney et al. (2003) 9	F	27	20	After childbirth	8 weeks	Excision	7 months
Rehman et al. (2015) 10	M	28	35	ND	4 weeks	Excision	Recurred after 3 weeks
						Re-excision	12 weeks
Thomas et al. (2014) 11	F	25	ND	Ear piercing	3 weeks	Excision	ND
Magliulo et al. (2014) 12	M	43	5	ND	3 months	Excision	6 months
Hsu et al. (2008) 13	M	27	4/4	Ear picking	4 weeks	Laser excision	ND
Song et al. (2018) 14	F	30	5/4	Ear picking Pregnancy	ND	Excision	2 months
Casler et al. (1989) 15	M	23	ND	Nail Scratch	3 months	Laser excision	6 months

PG is characterized by rapid growth over weeks and months. Although the patient in the present case could not recall its development, all previously reported cases showed rapid lesion growth within 3 months. Its pathogenesis is uncertain, but most hypotheses describe the development of PG as a hyperplastic, neovascular response to an angiogenic stimulus. ¹ This is supported by its common development in preexisting vascular lesions and during pregnancy. The effect of female steroid hormones during pregnancy on the pathogenesis of PG has been confirmed through basic research. ¹⁶ It was found that hormones increase the expression of angiogenic factors in the inflamed tissue and reduce granuloma cell death to prolong the angiogenic effect. When this angiogenic stimulus disappears after delivery, PG typically recedes spontaneously. ¹⁷ However, PG has also been reported to appear following childbirth.^7,8 Hormones are thought to play a role in the development of PGs. However, there are individual differences in when, how, and by what they are affected. Trauma is also an important factor and can be classified as acute and mechanical, such as ear piercing; ¹¹ chronic and mild, such as nail scratches;^7,15 or simple cotton bud usage.^13,14 The cause in this case could be the frequent touching by the patient.

Although some individuals may experience spontaneous regression,^18-20 surgical treatment is usually necessary because of frequent bleeding, obstruction, and cosmetic aspects. Various modalities have been utilized to treat PG, including full-thickness excision, shave excision, curettage, laser therapy, and cryotherapy. A review compared the results of 19 treatment methods for 1162 cutaneous PGs. ²¹ According to this report, surgical excision showed the lowest recurrence rate (2.94%), whereas blunt removal followed by cauterization with silver nitrate showed the highest recurrence rate (15.38%). Recurrence can occur when complete excision is not achieved. The EAC is a difficult structure for surgical access because of its narrow shape and limited amount of soft tissue; thus, there is a high possibility that remnants will remain upon removal of the lesion. A case of recurrence among the EAC lesions has been reported previously. The lesion was a 35-mm large PG that showed immediate recurrence after surgical excision. ¹⁰ After the reoperation, in which the lesion was excised down to the perichondrium level, as in the present case, there was no subsequent recurrence. In the external ear, most defects would heal by second-intention if the cartilaginous structures are intact. ²² Therefore, while planning surgical removal of the PG in the EAC, it is recommended to excise the lesion sufficiently down to the perichondrium.

A variety of benign and malignant tumors occur in the EAC; thus, differentiation of these tumors is important. Although it is very rare for PGs to occur in the EAC, it can be suspected in conditions such as after acute and/or chronic trauma, hormonal changes or systemic drug administration, rapid growth, and easy bleeding tendency with a friable surface. Some PGs may spontaneously resolve, but when they cause symptoms, excision is recommended for treatment and diagnosis. In the case of excision, the tumor should be excised down to the perichondrium level to prevent recurrence. Although PG mainly occurs in a solitary form, the present case shows a new clinical variation where multiple PGs were present in the EAC.