Final answer:
Leiomyomas are benign smooth muscle tumors that arise from the myometrium layer of the uterus, typically diagnosed by ultrasound. They can be confirmed through histology after a biopsy if necessary to rule out malignancy.
Step-by-step explanation:
Leiomyomas, commonly known as fibroids, are benign smooth muscle tumors that predominantly arise from the myometrium, which is the middle layer of the uterus consisting of smooth muscle tissue. The myometrial layer is responsible for the powerful contractions during childbirth and menstrual periods. Leiomyomas are typically diagnosed through imaging modalities, with ultrasound being the most common non-invasive technique used to detect these tumors. A definitive diagnosis of leiomyomas can be confirmed by histology, where a tissue sample is examined under a microscope. However, leiomyomas are not malignant, do not contain fluid-like cysts, and are not characterized by inflammation.
To distinguish between benign and malignant growths, such as distinguishing leiomyomas from a potential malignant neoplasm, a biopsy might be necessary. The biopsy involves taking a sample of the tumor tissue and analyzing it for cancerous cells. Although it is rare for leiomyomas to transform into cancer, this step is crucial when the diagnosis is uncertain or if there's rapid growth suggestive of malignancy. In summary, the correct answer to the question would be option a. Benign smooth muscle tumors, diagnosed by ultrasound.