Challenging diagnosis of an unusual solitary pulmonary nodule

We describe the case of a 64-year-old woman with a solitary pulmonary nodule and a previous breast carcinoma whose diagnosis of histoplasmoma was established only after surgical resection and appropriate stains. It is important not to confuse these two diseases as this will prevent inappropriate medical treatment. Limited surgery is indicated for the treatment of these circumscribed lesions.     

Pulmonary hyalinizing granuloma: a rare cause of a solitary pulmonary nodule.

Pulmonary hyalinizing granulomata are unusual, noninfectious lesions of the lung of uncertain etiology that probably represent an exaggerated immune response. They present radiographically as noncalcified solitary or multiple pulmonary nodules, thereby mimicking primary or metastatic malignancy. The article discusses a case of this rare entity that presented as a solitary pulmonary nodule.     

Human pulmonary dirofilariasis presenting as a solitary pulmonary nodule.

A case of human pulmonary dirofilariasis had positive serologic testing postoperatively. Increased awareness of this entity as a cause of solitary pulmonary nodules may lead to preoperative serologic and intradermal testing, and to the possibility of arriving at a preoperative diagnosis.     

Cytomegaloviral infection presenting as a solitary pulmonary nodule.

Cytomegaloviral infection presenting in an immunologically compromised host as a solitary pulmonary nodule has not previously been reported. A patient with a renal transplant and with no pulmonary symptoms was noted to have a single nodule on a chest roentgenogram. At autopsy, this proved to be secondary to cytomegaloviral infection. Differential diagnostic considerations in the immunosuppressed patient are discussed.     

Intraparenchymal solitary fibrous tumor of the lung: an uncommon cause of a pulmonary nodule

Solitary fibrous tumor of the lung is a rare mesenchymal tumor entity that has been characterized histologically. Its CT features have not been described before in the radiologic literature. We present the clinical, radiologic, and imaging features of a solitary fibrous tumor of the lung. The lesion we describe demonstrated slow growth and well defined margins. Specifically, we demonstrate its avid heterogeneous enhancement following intravenous contrast administration. Although rare, the diagnosis should be considered in asymptomatic slow growing pulmonary nodules with similar features.     

Evaluation of the solitary pulmonary nodule

The solitary pulmonary nodule represents a common diagnostic challenge for clinicians. While most are benign, a significant number represent early, potentially curable lung cancers. With the increased utilisation of chest computed tomography, solitary pulmonary nodules are increasingly being identified and with lung cancer screening programmes now on the horizon globally, it is crucial clinicians are familiar with the evaluation and management of solitary pulmonary nodules. Through the evaluation of patient risk factors combined with computed tomography characteristics of solitary pulmonary nodules, including size, growth rate, margin characteristics, calcification, density and location; a clinician can assess the risk of malignancy. This article provides an up to date review of the imaging features of both benign and malignant solitary pulmonary nodules to assist in the identification of nodules that require histological confirmation or ongoing surveillance. In addition, we summarise the newly updated Fleischner Society Guidelines that provide clinicians with a framework for the evaluation and management of solitary pulmonary nodules.     

Computerized tomographic densitometry of the solitary pulmonary nodule using a nodule phantom

The successful application of computerized tomographic density analysis for evaluating the solitary pulmonary nodule has previously been described and the technique has since been simplified by using a calcium-equivalent nodule reference phantom. Because published experience with this technique remains limited, the current research reports the Cleveland Clinic experience with the CIRS model III pulmonary nodule reference phantom. Without knowledge of the final diagnosis, the nodule phantom was used as the standard for categorizing 31 nodules in 29 patients as either benign or indeterminate. Secure diagnoses were obtained in all cases. Eleven nodules were called benign and ten proved so, whereas 20 nodules were classified as indeterminate. One lesion, an adenocarcinoma, was falsely called benign using this technique. The excellent density discrimination achieved with CT makes this a superior tool for analysis of the solitary pulmonary nodule, and the nodule reference phantom has greatly simplified the technique of CT densitometry. As demonstrated by this and prior studies, calcification is not a unique feature of the benign lesion and successful clinical application of this technique requires cautious interpretation of results.     

Imaging evaluation of the solitary pulmonary nodule

The solitary pulmonary nodule (SPN) is a common diagnostic problem facing the pulmonologist. The incidence of SPNs is increasing primarily because of the increasing use of multidetector CT scanning for the evaluation of chest disease. This article reviews the radiologic assessment of the SPN, with a focus on thin-section CT, positron emission tomography, and CT-guided transthoracic needle biopsy in the characterization of SPNs. The incorporation of clinical factors, local practice patterns and expertise, and access to technology will guide the diagnostic evaluation in a given patient. An evidence-based diagnostic algortihm for SPN evaluation will be proposed.     

Mycobacterium abscessus pulmonary infection presenting as a solitary pulmonary nodule

Nontuberculous mycobacterial pulmonary infection is a rare cause of a solitary pulmonary nodule. All previously reported cases were caused by Mycobacterium avium complex, and a solitary pulmonary nodule caused by other NTM species has been very rarely reported. We describe the first case of Mycobacterium abscessus infection presenting as a solitary pulmonary nodule in a 51-year-old asymptomatic adult patient.     

Management strategies for the solitary pulmonary nodule

PURPOSE OF REVIEW: The challenge of diagnosis and management of solitary pulmonary nodules is among the most common yet most important areas of pulmonary medicine. Ideally, the goal of diagnosis and management is to promptly bring to surgery all patients with operable malignant nodules while avoiding unnecessary thoracotomy in patients with benign disease. RECENT FINDINGS: Effective management of the solitary pulmonary nodule depends upon an understanding of decision analysis principles so that diverse technologies can be integrated into a systematic approach. SUMMARY: In almost all patients computed tomography (CT) is the best first step. Three key questions can then help guide the workup of the SPN. These are what is the pretest probability of cancer, what is the risk of surgical complications, and does the appearance of the nodule on CT scan suggest a benign or malignant etiology. In patients with average surgical risk, positron emission tomography (PET) scan is warranted when there is discordance between pretest probability of cancer and the appearance of the nodule on CT scan. Thus, when either the patient has a low risk of cancer and the CT suggests a malignant origin, or when there is high risk of cancer and the CT appears benign, PET scan will be cost effective. In most other situations, PET scanning is only marginally more effective than CT and fine needle aspiration strategies but costs much more.     

Diagnostic approach to solitary pulmonary nodule

The solitary pulmonary nodule is a common radiologic abnormality that is often detected incidentally. Many malignant and benign diseases can present as a solitary pulmonary nodule on a chest roentgenogram. It is important to differentiate malignant nodules from benign nodules in the least invasive way and to make as specific and an accurate diagnosis as possible. In this paper, a diagnostic approach to the solitary pulmonary nodule was discussed.     

Thoracoscopic Nd:YAG laser resection of a solitary pulmonary nodule.

Advances in endoscopic surgical techniques and laser technology have expanded the role of thoracoscopy. We report a thoracoscopic resection of a benign pulmonary lesion. A 44-year-old man underwent a successful Nd:YAG laser-assisted thoracoscopic resection of a peripheral lung hamartoma. The patient's postoperative course was uncomplicated. Thoracotomy with its attendant morbidity was avoided. Continued success with thoracoscopic resection will have a significant impact on the management of select patients with peripheral, solitary pulmonary nodules.