Lung

The upper lobe tissue measured 17 x 11 x 5.5 cm. and contained a mass that measured 8.0 x 6.0 x 6.0 cm in diameter having a reddish-tan, soft and friable cut surface. The mass appeared to arise in a segmental bronchus and extended into the surrounding parenchyma (Figure 1A). The microscopic sections showed a tumor composed of large pleomorphic cells, spindle cells, and scattered giant cells (Figure 2 arrow). Numerous mitotic figures were seen. No gland formation or other differentiating features were observed. The initial pathologic diagnosis was: nonsmall cell carcinoma of lung.

Jejunum

The resected specimen consisted of a 15.0-cm segment of small intestine. The lumen was eroded into by a mesenteric mass that measured 7.0 cm in diameter. The tumor was yellowish-tan with extensive hemorrhage and necrosis. A segment of large intestine was adherent to the small bowel by fibrous adhesions but was not involved by the neoplasm. Extensive fibrinosuppurative exudates involved the serosa of both small and large intestines and the mesentery (Figure 3). The microscopic appearance of the tumor was identical to that of the previously resected lung mass, consisting of undifferentiated pleomorphic cells, spindle cells and giant cells (Figure 4: the arrow shows an example of multinucleated giant cell characteristic of this neoplasm). The diagnosis was: metastatic nonsmall cell carcinoma of lung.

A number of special stains and immunohisto-chemical (IHC) stains were performed on the lung tumor with the following results:

Negative: Mucin, CK-20, CK-7, CD34, SI00, SMA, and HMB-45 Positive: AE (keratin), focal, and vimentin, strongly reactive.

The stain pattern and histologic appearance was suggestive of a rare subtype that resembled a carcinosarcoma. Because of the unusual presentation and histological pattern, the tissue specimens were referred to the Armed Forces Institute of Pathology (AFIP) for consultation, and additional stains were performed with the following results:

Negative: EMA, Ber-EP4, CEA, S-100, HMB-45, Tyrosinase, Melan A, TTF-1, Inhibin, ER, PR, AFP, CD117 [KIT], CD34, Actin, SMA, Desmin, Myo-Dl, Myoglobin CD20, CD79, CD3, CD5, CD43, LCA, LeuMl,CD21. pharmacy uk

Figure 1. Resected primary lung tumor

Figure 1. Resected primary lung tumor. The arrow (A) shows the main stem bronchus opening into the necrotic tumor.
Figure 2. Photomicrograph of a lung tumor, which shows large polygonal malignant tumor cells with eosinophilic cytoplasm, varying in size and shape; hyperchromatic nuclei; and numerous multinucleated tumor giant cells, such as the one shown at the arrow.
Figure 3. Segment of jejunum with a mesenteric mass (B) that erodes into the lumen with partial obstruction and proximal dilatation.
Figure 4. photomicrograph of the small-bowel lesion which is similar to the lung lesion in Figure 2. Note the multinucleated giant cell at the arrow.

Positive: Pancytokeratin, and focal CD30.

The AFIP interpretation, based on the morphology, phenotype and pattern of spread was:

1. Lung (LUL): Pleomorphic (giant cell and spindle cell) carcinoma.

2. Jejunum: Metastatic pleomorphic carcinoma.

The report noted that pleomorphic carcinoma has a propensity to metastasize to the small bowel. buy antibiotics canada