Sandbox lung cancer differential

• Overlapping histologic features differentiation of primary and secondary tumors are difficult.
• Topography, size and form of pulmonary growth pattern are important aspects for the differential diagnosis.
• Primary lung tumors are mainly localized in upper lobes as singular nodules, metastases in lower lobes as multiple lesions.
• On the contarary, endobronchial primary or secondary squamous cell carcinomas findings of severe dysplasia and CIS of the bronchial epithelium are important.
• Stroma and vascularisation pattern of primary and secondary lung tumors differ in distribution, arrangement and extracellular matrix components.
• Pulmonary vascular changes in primary tumors are characterized by vascular infiltration, destruction and occlusion whereas in secondary tumors intravascular embolisation and extravasation predominate.

Malignant lung carcnimoma
			Epidemiology	Topography	Histology	Immunohistochemistry		Topography	Pulmonary growth pattern	Mets	Other differentiating features
Squamous cell carcinoma	Papillary		Cigarette smokers Arsenic	Centrally in the mainstem	Exophytic and endobronchial growth. Limited amount of intraepithelial spread without invasion.
	Clear cell				Predominantly composed of cells with clear cytoplasm.
	Small cell				Poorly differentiated with small tumor cells Focal squamous differentiation. Lacks the characteristic nuclear features of small cell carcinoma. Focal intercellular bridges or keratinization.
	Basaloid				Prominent peripheral palisading of nuclei. Poorly differentiated Carcinomas with an extensive basaloid pattern but lacking squamous differentiation
Small cell carcinoma	Combined small cell carcinoma
Adeno carcinoma	Adenocarcinoma, mixed sub type
	Acinar adenocarcinoma
	Papillary adenocarcinoma
	Bronchio-alveolar carcinoma	Non-mucinous
		Mucinous
		Mixed non-mucinous and mucinous or indeterminate
	Solid adenocarcinoma with mucin production	Fetal adenocarcinoma
		Mucinous (“colloid”) carcinoma
		Mucinous cystadenocarcinoma
		Signet ring adenocarcinoma
		Clear cell adenocarcinoma
Large cell carcinoma	Giant-cell carcinoma of the lung
	Basaloid large cell carcinoma of the lung
	Clear cell carcinoma of the lung
	Lymphoepithelioma-like carcinoma of the lung
	Large-cell lung carcinoma with rhabdoid phenotype
	Large cell neuroendocrine carcinoma of the lung
Sarcomatoid carcinoma	Pleomorphic carcinoma
	Carcinosarcoma
	Spindle cell carcinoma
	Giant cell carcinoma
	Pulmonary blastoma
Carcinoid tumour	Typical carcinoid
	Atypical carcinoid
Salivary gland tumours	Mucoepidermoid carcinoma
	Adenoid cystic carcinoma
	Epithelial-myoepithelial carcinoma
Preinvasive lesions	Squamous carcinoma in situ
	Atypical adenomatous hyperplasia
	Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia
Mesenchymal tumors	Epithelioid haemangioendothelioma
	Angiosarcoma
	Pleuropulmonary blastoma
	Chondroma
	Congenital peribronchial myofibroblastic tumor
	Diffuse pulmonary lymphangiomatosis
	Inflammatory myofibroblastic tumor
	Synovial sarcoma Monophasic Biphasic
	Pulmonary artery sarcoma
	Pulmonary vein sarcoma

Benign lung tumor
			Epidemiology	Histopathology	Immunohistochemistry	Topography	Spread
Papilloma	Squamous cell papilloma	Exophytic
		Inverted
	Glandular papilloma
	Mixed squamous cell and glandular papilloma
Adenomas	Alveolar adenoma
	Papillary adenoma
	Adenomas of the salivary gland type	Mucous gland adenoma
		Pleomorphic adenoma
	Mucinous cystadenoma
	Lymphoproliferative tumors	Marginal zone B-cell lymphoma of the MALT type
		Diffuse large B-cell lymphoma
		Lymphomatoid granulomatosis
		Langerhans cell histiocytosis
Miscellaneous tumors	Harmatoma
	Sclerosing hemangioma
	Clear cell tumor
	Germ cell tumors	Mature tratoma
		Immature teratoma
		Other germ cell tumours
	Intrapulmonary thymoma
	Melanoma
Metastatic tumors