A Report of 10 Individuals with Weathering Nodules and Review of the Literature

Abstract

Weathering nodules are a benign skin condition that usually present as papules on the helices of patients with significant prior sun exposure. They are easily recognized clinically and blanch upon application of pressure to the adjacent helical rim: a positive blanch sign. We describe the clinical presentation of weathering nodules in 10 patients, nine men and one woman, aging from 38 to 70 (median 59), and their associated risk factors. Eight patients had a history of actinic keratosis, three had a history of nonmelanoma skin cancer, and all patients had increased Sun exposure through outdoor activities. Weathering nodules are rarely mentioned in the literature and may be confused with other cutaneous disorders. Therefore, it is paramount for clinicians to become familiar with weathering nodules and include them in the differential diagnosis of ear nodules. Appropriate diagnosis will help avoid unnecessary biopsies while reassuring the patient that the lesions are benign.

Introduction

What was known?

Weathering nodules are a benign condition that have rarely been reported in the literature. Risk factors for developing this condition include light skin color, sun exposure, and old age. Pressure applied to the adjacent helical rim results not only in accentuation, but also blanching of the nodules.

Weathering nodules are a benign, asymptomatic condition with a characteristic clinical appearance of skin colored to white papules or nodules. They are most often found on the helix of the ear, may be bilateral or unilateral, multiple or single, and usually measure 2–3 mm in width and 1–2 mm in height.[1] Application of pressure to the adjacent helical rim blanches the nodules. We describe 10 patients who presented with weathering nodules and summarize the possible risk factors that predisposed them to develop this condition.

Case Report

Over a 9-month period, a clinical diagnosis of weathering nodules was made in 10 patients who presented to our clinic. Characteristics recorded for these patients including age, gender, race, history of sun exposure, location and number of weathering nodules, as well as previous diagnoses of actinic keratosis and/or nonmelanoma skin cancer were collected and are summarized below [Table 1].

Table 1.

Clinical characteristics of 10 patients with weathering nodules^a

The patients with weathering nodules, diagnosed by clinical presentation, included 9 men, aging 38-70 years old (median age was 56) and one woman who was 70 years old. The lesions were slightly whiter than the skin surrounding them [Figure 1], had a smooth surface with occasional scaling, and blanched with pressure applied to the adjacent helix [Figures 2 and 3]. The majority of nodules measured approximately 2–3 mm in width and 1–2 mm in height, were present along the helix in all patients and along the antihelix as well in three patients (Cases 3, 6, and 8) [Figure 1]. One patient had a single lesion on the helix of his right ear (Case 3); the other patients displayed nodules that were multiple (Case 10) and grouped (Case 9) [Figure 4], occasionally forming a scalloped appearance (Case 8) [Figure 1]. The female patient (Case 10) had multiple lesions on the right ear and a single lesion, as well as Darwin's tubercle, on the other ear. One of the men also had a Darwin's tubercle on his right ear (Case 1) [Figure 3].

Figure 1.

Weathering nodules on the helix and antihelix of the right ear are whiter than the surrounding skin of a man who had been exposed to ionizing radiation at 4 years old, and is also an avid surfer (Case 8)

Figure 2.

The right ear weathering nodules of a man with a history of Poikiloderma of Civatte (Case 4) are prominently seen when pressure is applied to the ear, which also caused the lesions blanch

Figure 3.

(a and b) A 38-year-old man, with excessive sun exposure since childhood, who surfs (Case 1). In addition to Darwin's tubercle (a congenital variant of normal ear morphology where there is a thickening of the helix), subtle appearing weathering nodules on both the helix and the antihelix of the right ear are observed (a). However, after pressure on the helix, the weathering nodules become more apparent (b)

Figure 4.

A man with grouped weathering nodules on the left ear helical rim and a history of excessive sun exposure since childhood (Case 9)

These lesions were all incidental findings on examination. In all patients, pressure was placed on the helical rim and the lesions were noted to blanch (positive blanch sign) which clinically confirmed the diagnosis. Biopsies were not performed. None of the patients requested treatment for their lesions.

All the patients confirmed greater than normal sun exposure, including outdoor activities or professions and lack of sunscreen use since childhood. Eight patients (Cases 1 and 4–10) had concurrent actinic keratosis and three (Cases 6, 8, and 9) had actinically-induced malignancy. One patient (Case 8) had a history of bilateral auricular radiation therapy to cure his conductive deafness when he was 4 years old; he reports that his weathering nodules have been present since he was 8 years old, implying that nonsolar radiation may play a role in the pathogenesis of weathering nodules. One patient (Case 5) was receiving prednisone and subsequently azathioprine for ulcerative colitis for at least 2 years; hence, it is possible that systemic immune suppression, in addition to his sun exposure, may have contributed to the development of his weathering nodules. Two patients (Cases 1 and 10) had Darwin's tubercle which correlates with the incidence of this congenital variant of ear morphology in the general population.[2]

Discussion

Weathering nodules are a benign condition with a characteristic clinical appearance of white to skin-colored papules about the ear, usually on the helix; pressure on the adjacent helical rim not only enhances their presentation, but also results in blanching of the lesions: a positive blanch sign. Weathering nodules were not recognized as a distinct condition until Kavanagh et al. published a case series in 1996 coining the term “weathering nodules.”[1] Before this time, there were other case reports that likely described weathering nodules, but did not have a distinct medical diagnosis for them.[3]

Increased age is likely a risk factor for developing weathering nodules, as reflected by the advanced age of the patients reported to have this condition (median of 56 years old in this study); however, this study presents the first two pediatric cases of weathering nodules in the literature, as one man (Case 8) claims to have had weathering nodules present from 8 years; yet he also had a history of radiotherapy to his ears 4 years earlier, and the woman (Case 10) confirmed that nodules were present since she was 9 years old. Thus, advanced age is likely a strong risk factor for developing these nodules, but it may not be integral to the pathogenesis of the condition.

A predilection for weathering nodules to occur in men is anecdotally supported by the nine men and one woman in this study. Indeed, individual reports that describe women with this condition are rare. The first woman in whom weathering nodules were reported was 35 years old, had bilateral lesions, and a 20 year history of increased time spent on outdoors.[4]

However, a more recent epidemiologic study of 400 patients performed on a tropical population (Brazil) found an increased incidence of weathering nodules in women.[5] They observed weathering nodules in 81 of 230 women as compared to 74 of 170 men.[5] It has been proposed that women's ears are normally protected from the sun by their long hair, protecting them from sun-induced ear damage.[4,6]

Weathering nodules were also found to be more common within the tropical population studied (38.8%, 155/400) when compared to a nontropical population (4%, 4/100).[1,5] These data support the hypothesis that sun exposure has a significant role in the pathogenesis of these lesions. In addition, weathering nodules were previously thought to be found exclusively in white- or light-skinned populations; indeed, they had previously been described as “a condition found on Caucasian men who have a history of significant cumulative sun exposure.”[7] Although this claim was substantiated by earlier individual case reports, an epidemiologic study recently described five patients (17%, 5/29) with Fitzpatrick skin phototype V who had weathering nodules.[5] However, to the best of our knowledge, no Fitzpatrick phototype VI patients with weathering nodules have been reported.

The morphology of these lesions is distinctive; they typically present on the helix of the ear as multiple, nontender, white nodules with smooth surfaces measuring 2–3 mm in diameter and 1–2 mm in height. Occasionally, they present with a gritty, scaling texture, which is suggestive of underlying cartilage.[1] Various other conditions may mimic weathering nodules, such as basal cell carcinoma, calcinosis cutis, chondrodermatitis nodularis helicis, elastotic nodules, follicular neoplasm (including trichilemmomas), keratoacanthoma, sarcoidosis, squamous cell carcinoma, and tophi.[8] Chondrodermatitis nodularis helicis lesions are typically painful, pink or gray, often with a central crust-like scale or ulceration.[1] Elastotic nodules can be recognized as bilateral, pale, semi-translucent aggregates of pink-white material, with an orange-peel-like surface and associated pain.[6,9]

Although the precise pathogenesis is unknown, consistent history of sun exposure and the presence of actinic damage suggest a role of ultraviolet light. This is supported by the epidermal atrophy, solar elastosis, and telangiectasias, which have been found to occur over the nodules and are known the consequences of solar damage.[7] The majority of our patients who presented with these nodules (8 out of 10) had concurrent actinically-induced cutaneous malignancy, premalignancy, or both. Increased sun exposure was also noted in all of our patients and is likely involved in the pathogenesis of these lesions.

One of our patients developed weathering nodules at 8 years of age, 4 years after receiving bilateral auricular radiation therapy for hearing loss. Although this treatment has been associated with many side effects, weathering nodules have not been described.[10] This individual is unique; aside from being the first case of pediatric weathering nodules, his clinical history suggests that the pathogenesis of weathering nodules may not only be caused by solar exposure, but may also result from other types of radiation exposure.

Histologically, the weathering nodules are made up of a spur of fibrous tissue with a focus of cartilage metaplasia. This metaplastic cartilage extends up from the disrupted perichondrium of the underlying cartilage.[1] In contrast, elastotic nodules have disorganized thick collagen fibers replacing much of the dermis.[9]

Weathering nodules are benign and asymptomatic. Treatment is not usually requested, unless it is for cosmetic reasons. However, cryotherapy has been used with good results in two patients who had no recurrence of the lesions.[1]

The sequelae of weathering nodules are well established. Spontaneous resolution of weathering nodules has not been reported. However, the prognosis is favorable since there are no reports of skin cancer developing from the lesions.

Conclusion

Weathering nodules are benign lesions that have an easily recognizable clinical appearance: Asymptomatic, white to flesh-colored papules on the helices of the ear. The lesions characteristically become more prominent and blanch when pressure is applied to the adjacent helical rim; we introduce the descriptive terminology of a positive “blanch sign” when this pathognomonic feature of weathering nodules is clinically confirmed. All the patients in this report had lesions with morphology consistent with weathering nodules and a positive blanch sign; in addition, they had a history of excess sun exposure or evidence of actinic damage. One of the patients had a pediatric onset of the condition following radiotherapy to the ears, raising the possibility that other forms of ionizing radiation, in addition to ultraviolet light, may have a potential role in the pathogenesis of this condition. Weathering nodules are rarely mentioned in textbooks or in the literature and may be confused with other cutaneous conditions. Therefore, it is paramount for clinicians to become familiar with the clinical presentation, epidemiology, and pathogenesis of these lesions to include them in the differential diagnosis of ear nodules. This will help avoid unnecessary biopsies as well as providing assurance of their benign behavior to patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

What is new?

Weathering nodules characteristically become more prominent and blanch when pressure is applied to the adjacent helical rim; we introduce the descriptive terminology of a positive “blanch sign” when this pathognomonic feature of weathering nodules is clinically confirmed. Actinic damage was previously thought to be fundamental in the development of these lesions; however, we report a patient with pediatric onset of the condition following radiotherapy to the ears. This anecdotally supports the hypothesis that other forms of ionizing radiation, in addition to ultraviolet light, may have a potential role in the pathogenesis of these lesions.