SEER Inquiry System - Report
Produced: 11/27/2024 11:40 AM
Question 20160019
Inquiry Details
References:
#1: WHO Class Lung Tumors
#2: ICD-O-3
Question:
Reportability--Lung: Is a case of pulmonary metastatic leiomyoma (favored) vs. low grade leiomyosarcoma reportable, and if so, what is the primary site and histology code? See Discussion.
Discussion:
Patient presents with an abnormal chest x-ray. PET reveals 4.6 cm left lower lobe mass and several additional bilateral nodules measuring up to 1.6 cm. Biopsy was recommended and is positive for metastatic histologically benign smooth muscle neoplasm. ER/PR are positive. Mayo consult on biopsy agrees with histology. The differential diagnosis includes benign metastasizing leiomyoma and low grade leiomyosarcoma. Comment: If these nodules remain small and do not progressively grow would consider this metastasizing leiomyoma. Physicians state bilateral pulmonary metastatic leiomyoma (favored) vs low grade leiomyosarcoma. Tamoxifen was started. Patient has a history of uterine fibroids. Several months later, imaging reveals stable bilateral multi pulmonary nodules and left lower lobe mass but persistent. Surgery was recommended but cancelled due to insurance.
Answer:
This case is not reportable based on the information provided. The histologic diagnosis is "metastatic histologically benign smooth muscle neoplasm." The physicians seem to agree with the histologic diagnosis, benign metastasizing leiomyoma (BML). The WHO classification and ICD-O-3 assign 8898/1 to "metastasizing leiomyoma." WHO states "This resembles a typical leiomyoma but it is found in the lungs of women with a history of typical uterine leiomyomas." A recent article states "Because of the hormone-sensitive characteristics of BML, treatments are based on hormonal manipulation along with either surgical or medical oophorectomy." Tamoxifen treatment is in keeping with the BML diagnosis.