Esophageal Leiomyoma

From Medscape – Sandeep Mukherjee, MB, BCh, MPH, FRCPC;

Background

Benign tumors of the esophagus are rare lesions that constitute less than 1% of esophageal neoplasms. Nearly two thirds of benign esophageal tumors are leiomyomas; the others mostly are polyps and cysts. Thus, leiomyomas are the most common benign tumors of the esophagus.[1]

Pathophysiology

Leiomyomas represent a hyperproliferation of interlacing bundles of smooth muscle cells that are well-demarcated by adjacent tissue or by a smooth connective tissue capsule. They usually arise as intramural growths, most commonly along the distal two thirds of the esophagus. They are multiple in approximately 5% of patients.

The majority of leiomyomas have been discovered incidentally during evaluation for dysphagia or during autopsy. Bleeding rarely occurs in cases of benign disease but typically is observed with leiomyosarcoma, the malignant counterpart of this tumor. The potential for malignant degeneration of leiomyomas is extremely small. In the distal esophagus, leiomyomas may reach large proportions and may encroach on the cardia of the stomach.

Epidemiology

Frequency

International

Esophageal leiomyomas comprise less than 0.6% of all esophageal neoplasms, both in the United States and worldwide.

Race

No known differences

Sex

No known differences

Age

Typically occur in individuals aged 20-50 years

History

  • Esophageal leiomyomas rarely cause symptoms when they are smaller than 5 cm in diameter.
  • Large tumors can cause dysphagia, vague retrosternal discomfort, chest pain, esophageal obstruction, and regurgitation.
  • Rarely, they can cause gastrointestinal bleeding, with erosion through the mucosa.

Physical

  • Other than the nonspecific symptoms associated with esophageal leiomyomas, very few physical findings are ever noted.
  • In extremely rare cases where severe esophageal obstruction is caused by a leiomyoma, weight loss and muscle wasting may be observed.

Imaging Studies

  • Esophageal leiomyoma can be visualized using barium swallow. The classic appearance is a smooth concave mass underlying intact mucosa. Distinct sharp angles are seen at the junction of the tumor and normal tissue. Encroachment onto the esophageal lumen usually is observed.
  • Esophageal ultrasonography can be helpful in demonstrating a smooth, typically round, mass located in the muscularis without encroachment into the overlying mucosa or underlying adventitia.
  • Esophagoscopy may reveal a nonspecific tumor in the wall of the esophagus, typically without mucosal involvement (ulceration or erosion).

Procedures

  • Upon endoscopy, the lesions are identified as mobile submucosal masses.
  • Esophagoscopy should be performed to rule out carcinoma. It is important to remember that if a leiomyoma is suspected at esophagoscopy, a biopsy should not be performed if it would cause scarring at the biopsy site, which would hamper definitive extramucosal resection at surgery. A brush cytology may be performed. A leiomyoma (especially an ulcerated one) routinely is biopsied through the endoscope without any problems occurring in the ability to resect at a later date. In fact, an ulcer in a leiomyoma may be considered much worse than a mucosal biopsy.
  • Esophageal ultrasonography has aided in the diagnosis of leiomyomas, which demonstrate a homogeneous region of hypoechogenicity juxtaposed with the overlying mucosa.
  • Endoscopic ultrasonography is a useful technique for diagnosing and reaching treatment decisions for esophageal leiomyoma.[5]

Histologic Findings

Histologically, the tumors are comprised of bundles of interlacing smooth muscle cells, well-demarcated by adjacent tissue or by a definitive connective tissue capsule. They are composed of fascicles of spindle cells that tend to intersect with each other at varying angles. The tumor cells have blunt-ended elongated nuclei and show minimal atypia with few mitotic figures.

Surgical Care

Surgical excision is recommended for symptomatic leiomyomas and those greater than 5 cm. Asymptomatic or smaller lesions should be followed periodically with barium swallow.

  • Resection is the only way to confirm that a tumor is not malignant. Periodic follow-up of smaller lesions is recommended because leiomyomas have a characteristic radiographic appearance, slow growth rate, and low risk of malignant degeneration.

    • Tumors of the middle third of the esophagus are approached using a right thoracotomy; tumors in the distal third of the esophagus are resected through a left thoracotomy.
    • The outer esophageal muscle is gently incised longitudinally in order to reveal the lesion. Careful dissection is performed to separate and remove the leiomyoma from the underlying submucosa.
    • If the mucosa has been opened during dissection, the underlying mucosa is reapproximated, followed by closure of the longitudinal muscle. Some authors have shown that large extramucosal defects may be left open without subsequent complications developing.
    • Segmental esophageal resection may be indicated for giant leiomyomas of the cardia.
  • While open surgical technique is the traditional mainstay of therapy for leiomyomas, combined esophagoscopy and video-assisted resection (thoracoscopy) or laparoscopic transhiatal resection are being increasingly performed.[6, 7, 8, 9]
  • Endoscopic removal of these tumors has been attempted. However, this technique cannot be considered standard of care.

Consultations

Thoracic surgeon

Prognosis

Following complete surgical resection, no recurrence has ever been reported.