The photos show an apparently biphasic malignancy. Figures 1~3 show an epithelial malignancy (carcinoma), while figures 4~6 show a high grade glioma (glioblastoma). The combination is certainly intriguing.

Peripheral palisading of neoplastic cells and formation of glandular spaces are present in the former, making it an adenocarcinoma. No hyalinized basement membrane material or cytoplasmic keratinizarion is detected to suggest adenoid cystic carcinoma or basaloid carcinoma. The tissue between epithelial nests is gliotic parenchyma that shows no hypercellularity, necrosis, or obvious atypical glial cells. The latter has congested vessels, hypercellularity, marked cytologic atypia and clear cut glial (astrocytic) differentiation in Figure 4 that are consistent with anaplastic astrocytoma or glioblastoma. I am not certain, but there may be tumor necrosis in Figure 6, which would make this a glioblastoma.

Two possibilities exist for such combination - (1) collision cancer (co-existing metastatic adenocarcinoma and glioblastoma), and (2) glioblastoma with epithelial metaplasia. In an elderly individual and with such a large area of adenocarcinoma that may not actually be located within the glioblastoma, possibility (1) is favored. Possibility (2) is a very rare occurrence. Metaplastic epithelial elements in glioblastomas can be either glandular or squamous or both, but the areas of involvement are usually small and typically surrounded by glioblastoma.

I wait to be educated.

马教授分析的精辟，这例我们发的胶质母细胞瘤伴转移癌（所谓碰撞瘤），患者拒绝进一步检查治疗，肺内未提示占位，但我们做了免疫组化TTF-1阳性。癌巢周围似乎有栅栏样排列，腺癌好像不太典型。过两天再把免疫组化结果传上。

高手对话啊!感谢月新老师的翻译,让我大开眼界.

该例我有两点不同意见:
1.胶质成分够诊断胶母吗?  个人认为还不够,坏死不典型,血管增生不明显,细胞异型性也不够;
2.上皮性成分一定是腺癌吗? 个人认为也不一定,更倾向于基底细胞样鳞癌,是否有神经内分泌分化?

此外,转移瘤引起的胶质细胞反应到底能有多重,是否会引起如本例相似的改变,我们无从得知.因此,我认为在诊断"碰撞瘤"或"癌在胶质母细胞瘤中"时应格外慎重,毕竟国内外并没有相关的公认的诊断标准.

AMEN, 胶母够了吧，血管内皮增生最后一张图片左下角非常明显，有点像肾小球样结构，肿瘤细胞丰富，有明显异型性（第四张），本例坏死也比较明显（未上传）。
癌的类型我们也感觉腺癌不太像，报了转移性低分化癌。

谢谢xiaohl

 同意xiaohl老师意见

 同意xiaohl老师意见