The patient is an 64 66 year old white male who presented with left sided back pain. Imaging showed a left perinephric retroperitoneal hematoma history of smoking, COPD, and a left renal lower pole cystic lesion diabetes. The patient presented with hemorrhage. Additional imaging showed numerous pulmonary lesions. A endobronchial ultrasound guided fine needle aspiration was scheduledincreased shortness of breath.

* Congestive heart failureDiabetes * Ventricular tachycardiaCOPD* Ischemic heart diseaseSquamous cell carcinoma of skin

* Coronary stent placementExcision of squamous cell carcinoma* Implant Removal of adenomatous polyp of AICDsigmoid colon

The concern is a primary renal malignancy with metastatic disease to lungsdifferential diagnosis includes worsening of COPD. An endobronchial ultrasound guided FNA CT imaging of chest is scheduled. An onsite rapid diagnosis by cytology was scheduledperformed.

* CT Abdomen Chest shows a large perinephric hematoma hilar lung mass and large low anterior structure in left lower pole suspicious for a hemorrhagic renal cell carcinomamultiple mediastinal lymph nodes showing increased uptake on PET scan.* CT Chest shows multiple small lung lesions measuring up to 13x12 mm in greatest dimension.

CytologicallyYoursCoW20131216Cytology1.jpg|4x 10x magnification of a 4R lymph nodepleural fluid(ThinPrep). Groups of cohesive epithelial appearing cells can be are seen on low power. Lymphoid tissue is not easily identified.CytologicallyYoursCoW20131216Cytology2.jpg|20x 40x magnification of a 4R lymph nodepleural fluid (ThinPrep). This is a cellular specimen with groups Cluster of atypical cells along what appear to be a papillary or papillary-like structure. Single cells are also dispersed in the background. The cells are haphazardly arrangedshowing nuclear pleomorphism and scant cytoplasm.CytologicallyYoursCoW20131216Cytology3.jpg|40x magnification of a 4R lymph nodepleural fluid (ThinPrep). On higher power, the nuclei appear mildly atypical Chromatin is irregular and the cytoplasm is delicate clumped with salt and finely vacuolated. The nuclear contours pepper appearance; although, occasional nucleoli are somewhat irregularalso seen.CytologicallyYoursCoW20131216Cytology4.jpg|Cell block 40x magnification of 4R lymph nodepleural fluid (ThinPrep). The cytoplasm does not appear as vacuolated on alcohol fixed cell block material, but the nuclei are relatively uniform, but somewhat atypicalSome nuclear molding can be appreciated and a mitotic figure is present. CytologicallyYoursCoW20131216Cytology5.jpg|Cell block of 4R lymph nodepleural fluid. The Group of malignant cells showing nuclear molding, scant cytoplasm does not appear as vacuolated on alcohol fixed cell block material, but the nuclei and salt and pepper chromatin. Nucleoli are relatively uniform, but somewhat atypicalalso seen.

CytologicallyYoursCoW20131216Cytology6.jpg|PAX8 CD56 on 4R lymph node pleural fluid shows positive nuclear cytoplasmic staining.CytologicallyYoursCoW20131216Cytology7.jpg|PAX8 Synaptophysin on 4R lymph node pleural fluid shows positive nuclear cytoplasmic staining.

====Resident QuestionsOther immunostains performed====* <spoiler text="What are other immunohistochemical stains that would be applicable in this case?">BerEp4 Positive* RCCMoc31 Faintly positive*CD10Calretinin Negative*PAX2TTF1 Negative*Kidney specific antigenChromogranin Positive</spoiler>* Synaptophysin Positive* CD56 Positive* Napsin A Negative

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* Rapid diagnosis: Non-small Small cell carcinoma.* Final diagnosis: Renal cell carcinoma.