Epithelioid leiomyoma of the larynx

Abstract

We describe the pathological features of a case of laryngeal epithelioid leiomyoma (leiomyoblastoma) which, to our knowledge, is the second case to be reported in the world literature. A review of the literature confirmed that leiomyoma as such is a very rare neoplasm in the larynx, and only 33 cases have been previously reported. The neoplasm was located in the left vocal cord and consisted of mainly epithelioid, round or spindle-shaped cells, often with clear cytoplasm, which were arranged predominantly in solid nests and sheets. The tumour cells showed positive immunoreactivity for smooth muscle actin and desmin. The tumour showed low mitotic activity and immunostaining with MIB 1 (Ki-67) accordingly revealed the occasional cell only to be positive, confirming a low proliferative activity in agreement with a benign neoplasm. Epithelioid leiomyomas located in other sites have been shown to act occasionally in a malignant fashion, and the necessity for careful long-term follow-up of the patient is therefore emphasized.

Recurrent laryngeal leiomyoma

“…Epithelioid leiomyomas located in other sites have been shown to act occasionally in a malignant fashion, and the necessity for careful long-term follow-up of the patient is therefore emphasized. [5] Definite diagnosis of leiomyoma depends on histological examination. The characteristic findings of simple leiomyoma are as follows: interlacing fascicles of spindle-shaped cells, cigar-shaped nuclei, eosinophilic cytoplasm, and a positive reaction to smooth-muscle actin or desmin by IHC.…”

Leiomyoma with atypical cells (atypical leiomyoma) in the larynx

“…In 1994, Hellquist et al . reported the second case of laryngeal epithelioid leiomyoma (leiomyoblastoma) and found 33 cases of laryngeal leiomyoma in the literature 9 . Thereafter, three cases of laryngeal leiomyoma have been reported 10 –12 .…”

Epithelioid leiomyosarcoma of the larynx

“…12,13 In the case presented, very few mitotic figures were found in the initial biopsy, perhaps as result of a sampling problem. In the excised specimen, however, mitotic figures were readily apparent, and cytologic atypia was more marked.…”

“…Histologically, the two previously reported cases of laryngeal epithelioid leiomyomas consisted of masses of oval cells with abundant eosinophilic cytoplasm containing clear vacuolar areas and round, centrally located nuclei. 12,13 Immunohistochemically, both were moderately to strongly positive for smooth muscle actin, although strong immunoreactivity for desmin was demonstrated by only one of the tumors. 13 Distinguishing between epithelioid leiomyoma and the epithelioid leiomyosarcoma is difficult.…”

“…12,13 Immunohistochemically, both were moderately to strongly positive for smooth muscle actin, although strong immunoreactivity for desmin was demonstrated by only one of the tumors. 13 Distinguishing between epithelioid leiomyoma and the epithelioid leiomyosarcoma is difficult. Smaller cell size, evidence of pleomorphism, and increased mitotic figures are often the only indications that a given tumor may behave in a malignant fashion.…”