Background: Pulmonary adenocarcinoma is a subtype of Non–Small Cell Lung Cancer. In pediatric oncology, primary lung cancer represents only 0.2% of all pediatric malignancies, and it is five times less likely than metastatic lung disease. It is an extremely rare etiology of pediatric primary lung cancer, as the most common cause is pleuropulmonary blastoma. In the literature, a systematic review merely identified 62 cases dating back to 1912. The reported cases seldom have known risk factors such as smoking or chemical exposure. Molecular changes, with the echinoderm microtubule-associated protein-like 4 and anaplastic lymphoma kinase (EML4-ALK) fusion correlated with younger age of presentation. Prognosis is grim with a reported overall survival of < 20%. Methods: Case report demonstrating diagnosis and clinical management of a patient with pediatric metastatic pulmonary adenocarcinoma. Results: A 14-year-old male presented with persistent emesis, weight loss, and fatigue despite months of non-diagnostic studies. A chest x-ray showed diffuse interstitial densities, effusions, and cardiomegaly. An echocardiogram showed a moderate pericardial effusion, requiring pericardiocentesis. Fluid Immunohistochemical staining was positive for Cytokeratin 7 (CK7), BerEp4, and partial transcription termination factor (TTF1), consistent with pulmonary adenocarcinoma. He had stage IVB with metastatic disease to the bones, liver, cervical lymph nodes, and bone marrow. Treatment initially included chemotherapy as per Keynote-407 (pembrolizumab, carboplatin and paclitaxel) due to continuous effusions, followed by protocol Keynote-189 (pembrolizumab, cisplatin, pemetrexed). Once his molecular testing revealed an EML4-ALK fusion, he was switched to oral therapy with the ALK inhibitor Alectinib. He achieved remission 9 months after starting therapy and is now 18 months from diagnosis. Conclusion: Pediatric pulmonary adenocarcinoma diagnosis can be extremely challenging given the broad and non-specific presentation in pediatrics. To our knowledge, this is the first reported case of an adolescent presenting with a pericardial effusion secondary to primary pulmonary adenocarcinoma, a rare malignancy. This case emphasizes the importance of molecular testing in guiding diagnosis and treatment. Although prognosis continues to be poor, this case offers hope for others newly diagnosed with pulmonary adenocarcinoma.
A) Chest x-ray at initial presentation demonstrating cardiomegaly and interstitial edema. B) CT showing anterior mediastinal mass protruding through the thoracic inlet. C) PET demonstrating anterior mediastinal and cervical lymph node hypermetabolic activity. D) PET showing hepatic and scattered osseous hypermetabolic lesions. E) Pericardial fluid cell block (400x) demonstrates cluster of malignant cells with irregular hyperchromatic basophilic nuclei, prominent nucleoli and eosinophilic cytoplasm. The nuclear to cytoplasmic ratio is increased. F,G,H) These images (200x) display positive immunohistochemical staining for CK7, Ber-EP4, and partial positivity for TTF1, respectively.
Citation: Journal of the National Comprehensive Cancer Network 21, 3.5; 10.6004/jnccn.2022.7234
A) Chest x-ray at initial presentation demonstrating cardiomegaly and interstitial edema. B) CT showing anterior mediastinal mass protruding through the thoracic inlet. C) PET demonstrating anterior mediastinal and cervical lymph node hypermetabolic activity. D) PET showing hepatic and scattered osseous hypermetabolic lesions. E) Pericardial fluid cell block (400x) demonstrates cluster of malignant cells with irregular hyperchromatic basophilic nuclei, prominent nucleoli and eosinophilic cytoplasm. The nuclear to cytoplasmic ratio is increased. F,G,H) These images (200x) display positive immunohistochemical staining for CK7, Ber-EP4, and partial positivity for TTF1, respectively.
Citation: Journal of the National Comprehensive Cancer Network 21, 3.5; 10.6004/jnccn.2022.7234
A) Chest x-ray at initial presentation demonstrating cardiomegaly and interstitial edema. B) CT showing anterior mediastinal mass protruding through the thoracic inlet. C) PET demonstrating anterior mediastinal and cervical lymph node hypermetabolic activity. D) PET showing hepatic and scattered osseous hypermetabolic lesions. E) Pericardial fluid cell block (400x) demonstrates cluster of malignant cells with irregular hyperchromatic basophilic nuclei, prominent nucleoli and eosinophilic cytoplasm. The nuclear to cytoplasmic ratio is increased. F,G,H) These images (200x) display positive immunohistochemical staining for CK7, Ber-EP4, and partial positivity for TTF1, respectively.
Citation: Journal of the National Comprehensive Cancer Network 21, 3.5; 10.6004/jnccn.2022.7234
