Variant of large cell carcinoma – a large cell neuroendocrine carcinoma: LCNEC that large cell carcinoma histology neuroendocrine tumors showed morphological characteristics, their differentiation is low, a vicious high between the biological behavior of atypical carcinoid and small cell cancer between. Majority of patients with a history of smoking. Clinically, most patients have symptoms of bronchial obstruction.
the naked eye: LCNEC was single nodule mass, clear boundary for the central and peripheral type, maximum tumor diameter of 1.3-8cm, an average of 3.0cm. Section the tumor was reddish-brown, white, or sallow, many accompanied by focal hemorrhage and necrosis.
microscope: the tumor cells are widely distributed evenly, and present the structural characteristics of neuroendocrine tumors. Large tumor cells, were polygonal, nuclear / cytoplasm ratio low, rich cytoplasm containing eosinophilic granules, fine or coarse chromatin, small nucleoli can be seen or not seen nucleoli. Mitotic common. Easy to see large necrosis. Rare tumor stroma, mainly thin-walled blood vessels and fibrous connective tissue.
Immunohistochemistry: LCNEC of epithelial markers were positive for antibodies, most of the LCNEC tumor cells to hormone antibodies, gastrin (gastrin) were also positive.
variant of large cell carcinoma – a large cell neuroendocrine carcinoma of electron microscopy: cell cytoplasm shows dense core granules, particle size of 100-270nm. In addition, large cell carcinoma in general, like, LCNEC seen between micro-glandular cells (adenoid differentiation) and desmosome structure (squamous differentiation). If the large cell neuroendocrine carcinoma associated with small cell carcinoma, is classified as a composite of small cell carcinoma type.
differential diagnosis: LCNEC be with SCLC, identification of poorly differentiated adenocarcinoma and poorly differentiated squamous cell carcinoma.
a. SCLC: Although the two were neuroendocrine tumors, but malignant SCLC higher degree of clinical surgery is generally not, but chemotherapy and radiotherapy. Histological differences between the two, in addition to cancer volume, there are a number of other morphological characters.
b. poorly differentiated adenocarcinoma: a small number of LCNEC are scattered tube-like structure formation, like low grade adenocarcinoma. But a closer look at these tube-like structures, in fact, rosettes structure. Rosettes and different: The former small and rules, radial-shaped or oval cells were trapped cavity-like structures in the nucleus of these cancer cells at the base of cavity margin strong eosinophilic cytoplasm or processes for the chamber, missing or occasional non-mucinous secretions.
c. poorly differentiated squamous cell carcinoma: some LCNEC organ-like structure is not obvious, obvious multiforme cells. If there is more of the spindle cells, showing large and small nests, chip block or beam distribution, also appears more interstitial lymphocyte infiltration, scales easily misdiagnosed as poorly differentiated LCNEC but a closer look shows the daisy group structure, the phenomenon can not see the bridge keratinized cells, squamous cell carcinoma does not have a hierarchical structure.
variant of large cell carcinoma – prognosis of large cell neuroendocrine carcinoma: relevant reports suggest LCNEC and adenocarcinoma than squamous cell carcinoma and poor prognosis.