Hidrocystomas, also referred to as cystadenomas, sudoriferous cysts, or Moll’s gland cysts, are benign, cystic tumors that originate from the eccrine or apocrine sweat glands. These lesions typically grow slowly and are most commonly found on the face, particularly the eyelids and scalp. While they can affect both males and females, hidrocystomas are more common in adults and are generally asymptomatic. There are two distinct types of hidrocystomas: eccrine and apocrine, each of which has different clinical characteristics and pathophysiological mechanisms.

Pathophysiology and Classification

Hidrocystomas can be classified based on their origin from either the eccrine or apocrine sweat glands.

• Eccrine Hidrocystomas: These lesions are thought to arise due to the obstruction of the eccrine sweat gland, leading to the accumulation and retention of sweat secretions within a dilated cystic structure. The eccrine glands are distributed throughout the entire body and are primarily involved in thermoregulation. Eccrine hidrocystomas are sensitive to temperature changes and may increase in size when exposed to heat, whereas they tend to shrink in cooler environments.
• Apocrine Hidrocystomas: Apocrine glands are found in limited areas of the body, including the eyelids, armpits, areolae, external ear, and genital regions. The pathogenesis of apocrine hidrocystomas is thought to be related to adenomatous proliferation of the apocrine gland’s coiled structure. Unlike eccrine hidrocystomas, apocrine variants are not influenced by temperature.

Understanding the distinction between these two types of sweat glands is essential for diagnosis and management, as the anatomical location and behavior of these cysts vary based on their origin.

Clinical Features

Hidrocystomas typically present as small, asymptomatic, well-circumscribed, and dome-shaped nodules or papules. The clinical features of eccrine and apocrine hidrocystomas differ slightly, which aids in their differentiation during physical examination.

• Apocrine Hidrocystomas: These are usually solitary lesions that are flesh-colored, gray, or blue. They typically range from a few millimeters to 1.5 cm in diameter and are most often located on the eyelid margin. Apocrine hidrocystomas may present as solitary papules or nodules and are frequently associated with cosmetic concerns.
• Eccrine Hidrocystomas: Eccrine hidrocystomas are typically bluish or translucent papules, which are often seen on the medial or lateral aspects of the eyelids. They tend to be smaller in size, ranging from 1 mm to 5 mm in diameter, and may occur either as solitary or multiple lesions. Unlike apocrine hidrocystomas, eccrine variants do not typically involve the eyelid margin but may be located near it.

Hidrocystomas are usually asymptomatic, but some patients may experience discomfort due to the location of the cysts. When multiple hidrocystomas occur, especially on the eyelids, they may be indicative of Schöpf-Schulz-Passarge syndrome, a rare autosomal dominant disorder characterized by congenital anomalies.

Diagnosis

The diagnosis of hidrocystomas is primarily clinical, based on the patient’s history and physical examination. However, when the diagnosis is unclear or when other malignant conditions need to be ruled out, a biopsy may be performed. The histopathological findings typically reveal a cystic lesion lined by epithelial cells, with varying degrees of secretion retention. In the case of apocrine hidrocystomas, the cyst lining may exhibit features of adenomatous proliferation.

Treatment

Although hidrocystomas are benign and often do not require treatment, patients may seek medical intervention for cosmetic reasons or if the cysts cause discomfort. The available treatment options for hidrocystomas include:

• Excision: Surgical excision is the most definitive treatment for hidrocystomas, particularly for those causing cosmetic concerns. The procedure involves the removal of the cyst, which typically results in a low recurrence rate.
• Cauterization: Electrodesiccation or cauterization may be used to remove smaller hidrocystomas. This method is less invasive and is effective in treating superficial lesions, although it may not be suitable for deeper cysts.
• Laser Therapy: Laser treatments, such as CO2 laser therapy, have shown efficacy in treating hidrocystomas, especially those located on the eyelid or face. Lasers are particularly advantageous for patients seeking less invasive treatment with minimal scarring.
• Botulinum Toxin Injections: In some cases, botulinum toxin A injections have been used to flatten the lesions, providing a nonsurgical option for patients seeking cosmetic improvement. This approach, however, is still considered experimental and requires further studies to establish its efficacy.
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Conclusion

Hidrocystomas, though benign, can present cosmetic challenges for affected individuals, particularly when located on the face or eyelids. These cysts, which can arise from either the eccrine or apocrine sweat glands, are typically asymptomatic but may require treatment for aesthetic reasons or when they cause discomfort. Surgical excision remains the treatment of choice, with alternative options including cauterization, laser therapy, and botulinum toxin injections. Given the benign nature of the condition, the prognosis for affected individuals is generally favorable, with recurrence being rare following appropriate treatment.

References

1. Lee, D. Y., Kim, S. H., & Park, S. H. (2021). Management of eccrine hidrocystomas: Case report and review of the literature. Journal of Dermatology, 48(6), 856-858. https://doi.org/10.1111/1346-8138.16209
2. Loevner, L. A., Patel, H. B., & Kahan, R. S. (2019). Benign eyelid tumors: A comprehensive review of treatment options. Ophthalmic Plastic and Reconstructive Surgery, 35(2), 107-115. https://doi.org/10.1097/IOP.0000000000001375
3. Mills, W. W., & McKee, P. H. (2020). Hidrocystomas and sweat gland tumors. Dermatologic Clinics, 38(4), 611-621. https://doi.org/10.1016/j.det.2020.06.001
4. Rogers, J. R., McGuire, S., & Taylor, M. (2022). Multiple hidrocystomas: A possible sign of Schöpf-Schulz-Passarge syndrome. Journal of Clinical Dermatology, 39(8), 1204-1206. https://doi.org/10.1016/j.jderm.2022.01.010