Pulmonary sequestration associated with increased serum tumor markers and elevated standard uptake value level in PET/CT: A case report and literature review

Clinical perspectives on serum tumor marker use in predicting prognosis and treatment response in advanced non-small cell lung cancer

The optimal positioning and usage of serum tumor markers (STMs) in advanced non-small cell lung cancer (NSCLC) care is still unclear. This review aimed to provide an overview of the potential use and value of STMs in routine advanced NSCLC care for the prediction of prognosis and treatment response. Radiological imaging and clinical symptoms have shown not to capture a patient's entire disease status in daily clinical practice. Since STM measurements allow for a rapid, minimally invasive, and safe evaluation of the patient's tumor status in real time, STMs can be used as companion decision-making support tools before start and during treatment. To overcome the limited sensitivity and specificity associated with the use of STMs, tests should only be applied in specific subgroups of patients and different test characteristics should be defined per clinical context in order to answer different clinical questions. The same approach can similarly be relevant when developing clinical applications for other (circulating) biomarkers. Future research should focus on the approaches described in this review to achieve STM test implementation in advanced NSCLC care.

Unravelling the mystery of a rare infection: a challenging case of pulmonary sequestration with Mycobacterium avium complex and the importance of a thorough microbiological investigation

Pulmonary sequestration is a rare congenital condition. It is a dysplastic lung tissue with a separate systemic blood supply and without a bronchial tree connection. The emergence of a superimposed infection can lead to its diagnosis, such as Staphylococcus aureus, Pseudomonas aeruginosa, Nocardia asteroids and Aspergillus sp pneumonia. Mycobacterium avium complex (MAC) superimposed disease is exceedingly rare. We report a case of a man in his third decade without known medical disorders presenting with a persistent cough. After an extensive microbiological workup, an MAC infection was diagnosed. An elevated carbohydrate antigen 19-9 (CA 19-9) was also noted. He was treated with antimycobacterial therapy and lobectomy resulting in clinical improvement and CA19-9 normalisation. This case illustrates the value of comprehensive microbiological investigations in patients with chronic respiratory symptoms and imaging findings that are not typical of bacterial pneumonia. Clinical studies remain needed to investigate the utility of CA 19-9 in a scoring system to guide MAC therapy.

Extralobar pulmonary sequestration with elevated serum neuron-specific enolase: A case report and review of the literature

RATIONALE

Pulmonary sequestration (PS) presenting with elevated serum tumor markers is rare, and it might be misdiagnosed as malignancy.

PATIENT CONCERNS

A 26-year-old asymptomatic male patient was admitted because the x-ray showed an intrathoracic lesion. Meanwhile, the serum neuron-specific enolase (NSE) was elevated. Three-dimensional computed tomography angiography revealed an isolated feeding vessel arising from the aorta.

DIAGNOSES

Extralobular PS was confirmed by computed tomography angiography and postoperative pathological staining.

INTERVENTIONS

Two-port thoracoscopic resection of the sequestrated lobe was performed.

OUTCOMES

The serum NSE decreased to within the normal range and persisted during the follow up of 10 months.

LESSONS

A thorough work-up should be considered for the PS patients presenting with abnormal serum NSE. Detailed knowledge regarding the relationship between NSE and PS necessitates further studies.

Lung Masses of Unusual Histologies Mimicking Malignancy: Flurodeoxyglucose Positron Emission Tomography-Computed Tomography Appearance

18F flurodeoxyglucose positron emission tomography-computed tomography (18F FDG PET-CT) is widely used in the evaluation of patients with lung mass suspicious for malignancy. In addition to malignancy, a variety of benign neoplasms and inflammatory lesions can arise in the lungs, many of which show increased FDG concentration, thereby mimicking malignancy. Awareness of the common mimics of lung cancer and a thorough understanding of their key imaging characteristics on CT as well as FDG PET is helpful in narrowing the differential diagnosis, eventually leading to appropriate therapy. In this article, we enlist these mimics and discuss their metabolic and morphologic characteristics and provide a pathophysiological basis for their FDG uptake.