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
			Histology	Immunohistochemistry	Other differentiating features	Topography	Pulmonary growth pattern	Mets
Squamous cell carcinoma	Papillary
	Clear cell
	Small cell
	Basaloid
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 lesions of carcinoma
Papillomas	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 Others
	Mucinous cystadenoma