A rare pleural mucinous cystadenocarcinoma mimicking loculated empyema initially: A case report

Pulmonary mucinous cystadenocarcinoma: an unusual presentation and literature review

Cystic lung disease is a group of heterogeneous pulmonary diseases resulting from hereditary/congenital disorders, systemic disorders and infectious causes among others. Pulmonary mucinous cystic neoplasia is a spectrum of neoplastic cystic diseases with abundant mucin, of which pulmonary mucinous cystadenocarcinoma (PMC) is a rare malignant subtype. We present a case of a 66-year-old man who presented with dyspnoea, cough, fatigue and weight loss. Imaging of his chest showed numerous cavitary lesions, and the diagnosis of PMC was made based on lung biopsy. He received palliative chemotherapy and died 1 year later. We present a literature review of PMC based on 26 reported cases, including our own.

Colloid Adenocarcinoma of the Lung: CT and PET/CT Findings in Seven Patients

OBJECTIVE

We aimed to assess CT and ¹⁸F-FDG PET/CT findings of colloid adenocarcinoma of the lung in seven patients.

MATERIALS AND METHODS

From 2010 to 2017, seven patients with surgically proven colloid adenocarcinoma of the lung were identified. CT (both enhanced and unenhanced) and PET/CT findings were analyzed, and the imaging features were compared with histopathologic reports. Clinical and demographic features were also analyzed.

RESULTS

In all cases except one, tumors showed low attenuation on unenhanced CT scans, ranging in attenuation from -16.5 to 20.7 HU (median, 9.2 HU). After contrast medium injection, enhancement was scant, so net enhancement ranged from 0.4 to 29.0 HU (median, 4.1 HU). All tumors had a lobulated contour. Stippled calcifications within the tumor were seen in one patient. The maximum standardized uptake value of tumors on PET/CT ranged from 1.5 to 4.5 (median, 3.5). In six of seven patients, FDG accumulation was seen in the tumor walls (n = 3, curvilinear uptake) or in both the tumor walls and tumor septa (n = 3, crisscross uptake). Six patients were alive without recurrence after a median follow-up period of 2.3 years (range, 2 months to 5 years). In one patient, who was alive at follow-up 4 years after imaging and had received adjuvant concurrent chemoradiation therapy after lobectomy, recurrent disease was detected 6 months after completion of the therapy.

CONCLUSION

On CT, pulmonary colloid adenocarcinomas present as lobulated homogeneously low-attenuation tumors. At PET, curvilinear or crisscross FDG uptake is seen within the tumor where tumor cells are lining the walls or septal structures.

18F-FDG PET/CT Imaging of Pulmonary Mucinous Cystadenocarcinoma with Signet Ring Cells

A 63-year-old male with a recently diagnosed right lung lesion was referred for staging. F-FDG PET/CT scan revealed a hypodense, cystic-like mass in the right upper lung lobe, which demonstrated low, diffuse ¹⁸F-FDG uptake, likely due to the presence of mucus, as well as intensely hypermetabolic right hilar and right paratracheal lymph nodes. Transbronchial biopsy revealed a primary pulmonary mucinous cystadenocarcinoma with the presence of signet ring cell carcinoma, a co-existence of two rare variants of lung adenocarcinoma. This case report demonstrates the metabolic phenotype along with the radiographic characteristics of this rare tumor and its metastases.