Bone marrow metastasis in primary bronchial mucoepidermoid carcinoma: a case report

Comprehensive review of solid tumor bone marrow metastasis

Bone marrow metastasis (BMM) of solid tumors refers to a group of diseases that originate from non-hematopoietic malignant tumor cells invading the bone marrow (BM) through complex metastatic patterns. If BMM identification is delayed, the disease will rapidly develop into disseminated carcinogenesis of the BM, which manifests as a series of hematological disorders and microangiopathic hemolytic anemia, leading to serious life-threatening conditions. Although the study of solid tumor BMM is receiving increasing attention, study remains limited, and most descriptions are derived from case reports. Currently, clinicians have insufficient understanding of BMM, and BMM occurrence is often not recognized early or treated effectively, resulting in high mortality rates. In this article, we review the epidemiology, molecular mechanisms, clinical diagnosis, treatment, and prognosis of solid tumor BMM.

Clinicopathological and multisection CT features of primary pulmonary mucoepidermoid carcinoma

AIM

To delineate the multisection computed tomography (MSCT) features and the clinical characteristics of primary pulmonary mucoepidermoid carcinoma (PMEC). Prognostic factors were also analysed.

MATERIALS AND METHODS

A retrospective study was undertaken to investigate the medical records and MSCT performance of histopathologically confirmed PMECs from 2007 to 2015.

RESULTS

A total of 83.3% of patients with high-grade PMECs were aged >40 years, whereas there were 1.5-times more women than men with low-grade PMECs. Cough (n=29) and haemoptysis (n=12) were the most common symptoms. Upon MSCT, 30 cases showed a round or lobulate mass, and few demonstrated bronchial-wall thickening or cavities. Distal obstruction (n=14) and "air crescent sign" (n=5) could be detected. Tumours showed mild (n=19), moderate (n=5), and marked enhancement (n=5). Moreover, 18 cases showed foci of low density in lesions. Mean survival for patients with low-grade PMECs was 59.2 months, whereas that for high-grade PMECs was 20.4 months; 3-year survival rates were 55% and 14%, respectively. Tumour staging was a significant independent predictor of survival according to the Cox proportional hazards model.

CONCLUSION

High-grade PMECs occurred more frequently in patients aged >40 years and were more predominant in men. Young females were predisposed to having low-grade PMECs. MSCT revealed an oval or lobulate mass with mild enhancement, as manifested by calcification and visible mucus lakes, which may be suggestive of PMECs. Furthermore, a central nodule or mass may suggest low-grade PMECs; high-grade PMECs tend to be peripheral and associated with lymph-node metastasis. Pathological grade, lymph node metastasis, and TNM stage correlate with the survival of patients with PMEC.