Pathology Notes

Practice question III answers Lung and pleural tumors © Jun Wang, MD, PhD   1. B. Malignant tumors composed of irregular glands lined by atypical cells are adenocarcinoma s . Abscess is characterized by collection of neutrophils and other inflammatory cells in a necrotic background, but do not have glandular growth. Metastatic renal cell carcinoma does not have glandular pattern and is negative for TTF-1. Small cell carcinoma has solid nests of cells with round to oval molding nuclei and scant cytoplasm. Squamous cell carcinoma has squamous differentiation characterized by intercellular bridges and keratin pearls . 2. D. TTF-1 is usually positive in adenocarcinomas of lung. Calretinin and WT-1 are positive for mesothelioma . Chromogranin is a neuroendocrine marker that is expressed in neuroendocrine tumors, including carcinoid , small cell carcinoma , and olfactory neuroblastoma . P63 is a marker for squamous cell differentiation and is positive for squamous cell carcinom

Practice questions III Lung and pleural tumors © Jun Wang, MD, PhD   1. Use this case and this image for next three questions . A 75-year-old woman presents with non-productive cough and a 15 lb weight loss in the past 6 months. She does not have fever or chest pain. She has a history of clear cell type renal cell carcinoma at age 57 and was treated with left nephrectomy. Her past medical history is otherwise unremarkable. She does not smoke cigarette nor drink alcohol. Radiologic examination reveals a 2.5 cm lesion in the right middle lobe. An image of the biopsy is shown. There are foci of necrosis with neutrophils. What is most likely the diagnosis?     ( Image credit: Yale Rosen from USA, CC BY-SA 2.0 <https://creativecommons.org/licenses/by-sa/2.0>, via Wikimedia Commons)   A. Abscess B. Adenocarcinoma C. Metastatic renal cell carcinoma D. Small cell carcinoma E. Squamous cell carcinoma   2. A 75-year-old woman presents with non-productive cough and a 15 lb weight