Minute pulmonary chemodectoma

Abstract

The minute chemodectomas of the lung belong to the paraganglioma group of neoplasms, which include carotid and aortic body tumors. They are frequently multiple, small in size, and are nearly always detected fortuitously on histologic examination of sections of a lung taken from an older patient. They are believed to arise from the normal chemoreceptors of the lung. There is no indication that these small neoplasms are functional. It has been proposed that pulmonary chemodectomas may be induced by pulmonary thromboemboli. This possibility gains some support from an analysis of 10 new cases and a review of 46 cases previously reported.

Progesterone receptor immunoreactivity in minute meningothelioid nodules of the lung

“…The low proliferative fraction and the lack of mitotic figures or cellular atypia suggest that these lesions are benign, slow-growing proliferations of arachnoid-like cells, although their reactive of neoplastic nature is still debated. A polyclonal origin of MNs has been recently proposed [13], and their higher prevalence in patients with thromboembolic disease, cardiac failure and various chronic pulmonary diseases with scarring, as well as in inhabitants of highaltitude regions, support the view that these lesions may represent hyperplastic growths induced by local hypoxia rather than true neoplasms [5,9,16]. Epidemiological data also support a reactive nature for pulmonary MNs.…”

“…In fact, a prevalence of one MN in every 200-300 unselected autopsies has been reported [3,10], and our findings of 11 such nodules in 6 of 540 patients with lung cancer is consistent with the above figures. The prevalence of MNs can still increase significantly to approximately one in 25 autopsies, if a specific search is made, especially in case of pulmonary embolism, cardiovascular disease and lung cancer [3,9,16]. Unfortunately, the 546 invariable expression of progesterone receptors does not help clarifying whether these lesions are reactive or neoplastic in nature.…”

“…Only one case was grossly discernible. In the past, these lesions have been considered to be miniature carotid body tumours, due to their close association with pulmonary veins [9,10]. Electron microscopy, however, has failed to show the characteristic dense-core granules of chemoreceptor cells, having instead demonstrated prominent desmosomes, cytoplasmic tangles of fibrils and complex interdigitating cell processes [5].…”

Minute pulmonary meningothelial-like nodules: clinicopathologic analysis of 121 patients

“…Minute pulmonary meningothelial-like nodules (MPMNs) consist of epithelioid cell nests or whorls in a "Zellballen"-like arrangement centered on small veins [1][2][3]. From their architecture, cytologic characteristics, and relationship with vessels, MPMNs were believed to have an oxygenmonitoring function, as a chemoreceptor, so Korn et al [3] reported these lesions as "pulmonary chemodectoma" in 1960.…”

Minute pulmonary meningothelial-like nodules simulating a metastatic lung adenocarcinoma: A case report

“…The patient population shows a marked female predominance. There appeared to be an association with specific conditions such as cardiac failure, chronic bronchitis and emphysema, thromboembolism and malignancy (3,5). They are uncommon, tumor-like lesions found in the pleura or parenchyma of the lung as solitary or multiple nodules.…”