Differential Diagnosis

The patient's presentation with multiple pulmonary nodules, mediastinal adenopathy, and a history of abnormal chest radiograph suggests a complex diagnosis. The following differential diagnosis is organized into categories:

• Single Most Likely Diagnosis
  • Metastatic Disease: The presence of at least 60 nodular and irregular mass lesions in the lungs, ranging in size from a few millimeters to 7.4 cm, is highly suggestive of metastatic disease. The patient's history of coronary artery bypass surgery and the presence of a left paracentral retrosternal mass lesion also support this diagnosis.
• Other Likely Diagnoses
  • Primary Pulmonary Neoplasia: The CT findings of multiple pulmonary nodules and mass lesions, including a spiculated 3 cm right hilar mass lesion and a 4.8 cm left hilar mass lesion, are also compatible with primary pulmonary neoplasia.
  • Lymphoma: The presence of mediastinal adenopathy and multiple lymph nodes in the pretracheal and AP window regions could suggest lymphoma.
• Do Not Miss Diagnoses
  • Infectious Disease (e.g., Tuberculosis or Fungal Infection): Although less likely, infectious diseases such as tuberculosis or fungal infections could present with similar radiographic findings, and missing these diagnoses could have significant consequences.
  • Sarcoidosis: This diagnosis could also present with mediastinal adenopathy and pulmonary nodules, and although less likely, it should not be missed due to its potential for significant morbidity.
• Rare Diagnoses
  • Pulmonary Arteriovenous Malformations: Although rare, pulmonary arteriovenous malformations could present with multiple pulmonary nodules, and this diagnosis should be considered in the differential.
  • Histiocytosis: This rare diagnosis could also present with multiple pulmonary nodules and should be considered in the differential, especially if other diagnoses are ruled out.