Ciliated Muconodular Papillary Tumor of the Lung: A Newly Defined Low-grade Malignant Tumor with CT Findings Reminiscent of Adenocarcinoma

Abstract

A ciliated muconodular papillary tumor has been reported to be a peripheral low-grade malignant tumor, consisting of ciliated columnar cells and goblet cells with basaloid cell proliferation. Although ciliated muconodular papillary tumors have not yet been classified according to the World Health Organization classification, they can pose diagnostic and therapeutic problems. Here we report a resected case of ciliated muconodular papillary tumor with computed tomography findings reminiscent of adenocarcinoma, showing a small irregular nodule adjacent to the intersegment pulmonary vein. There was no uptake of F-18 fluorodeoxyglucose positron emission tomography. The patient underwent surgical resection, and a lobectomy was performed because intraoperative needle biopsy suggested neoplastic proliferation. No EGFR mutations were detected. No recurrence was noted during 24-month follow-up after lobectomy.

Ciliated Muconodular Papillary Tumors of the Lung

“…Ten cases with characteristic features of CMPT as described in the literature [1][2][3][4][5] were identified between 2006 and 2014. The clinical and pathologic records were reviewed, and a histologic analysis of the resected specimens was performed.…”

“…The tumor showed an indolent course and nonatypical cytologic properties, so the authors suspected that CMPTs represented a benign neoplasm. Only 5 similar tumors have been subsequently reported as CMPTs in the English-language literature, [2][3][4][5] but its clinicopathologic features have not been analyzed in a sizable series. In addition, variable terminologies have been proposed for histologically similar, if not identical, tumors, including "solitary peripheral ciliated glandular papillomas," "mucinous adenomatous hyperplasia," and "peripheral pulmonary papillary/glandular neoplasms with ciliated cells," [6][7][8][9][10] and their relationship to CMPTs is poorly understood.…”

“…In addition, variable terminologies have been proposed for histologically similar, if not identical, tumors, including "solitary peripheral ciliated glandular papillomas," "mucinous adenomatous hyperplasia," and "peripheral pulmonary papillary/glandular neoplasms with ciliated cells," [6][7][8][9][10] and their relationship to CMPTs is poorly understood. Furthermore, the great majority of these reports originated from East Asia, [1][2][3][4][5][6][8][9][10] and these ciliated lesions do not seem to have received global attention.…”

Ciliated muconodular papillary tumor of the lung harboring BRAF V600E mutation and p16INK4a overexpression without proliferative activity may represent an example of oncogene-induced senescence

“…Ciliated muconodular papillary tumor (CMPT) is a recently defined lung tumor that shows a papillary or glandular proliferation of ciliated columnar cells, mucous cells, and basal cells surrounded by intra-alveolar mucin pools in the peripheral lung (1)(2)(3)(4)(5)(6). This type of tumor has bland cytologic features and all cases reported to date have consistently shown an indolent clinical course.…”

“…Recently, CMPTs have been encountered more frequently as the use of the low-dose computed tomography (CT) for screening of lung cancer has increased. Because CMPT is usually seen in the subpleural lung parenchyma as a solitary pulmonary nodule, it might be misdiagnosed as lung cancer clinically and radiologically (2).…”