When exhaustive keratin staining was combined with EMA staining on laryngeal SpCC, Thompson etal. Osteoclast-like giant cells can be present, resulting in histologic features resembling those seen in giant cell tumor of bone.
Fig. 10.118).425 Microscopically, the identifiable epithelial elements, when present, may show squamous differentiation, glandular differentiation, or be undifferentiated, thus resembling large cell carcinoma (Fig. On long-term clinical follow-up, no patient has had clinically malignant disease. Most SpCC will have some foci of clear squamous differentiation.
There is an extensively ulcerated surface covered by fibrinopurulent material (Fig. These SpCC can closely mimick exuberant granulation tissue (a major pitfall for the surgical pathologist), particularly on frozen section. 1a). Myogenic differentiation in spindle cell (sarcomatoid) carcinomas of the upper aerodigestive tract. Sarcomatoid carcinomas were historically defined in the 1999 World Health Organization classification. This leaves a significant minority of cases where there is no definitive light or immunohistochemical evidence of epithelial differentiation. and transmitted securely. SpCC also shows features of epithelial-mesenchymal transition, e.g., up-regulation of transcription repressors (Snail, Slug, SIP and Twist etc.) Most IMT pursue a benign clinical course. However, by current standards, adequate IHC analysis was not performed. These data strongly argue that transcriptionally active HPV is rare in these tumors and, thus, not a significant contributor to their development or outcomes. Spindle cell carcinoma is an unusual variant of SCC where part, or all, of the tumor resembles a sarcoma (Figure 28). There are numerous atypical spindle cell lesions which can present along the UADT mucosa. In the larynx, true sarcomas (with the exception of chondrosarcoma) and benign mesenchymal tumors are very rare. FOIA The patient may complain of swelling, pain, paresthesia, persistent ulceration, or bleeding. The .gov means its official. The 31 cases of spindle cell carcinoma were tested for p16 immunohistochemistry and either RNA in situ hybridization or RT-PCR for high-risk HPV. Spindle cell lesions can occur in head and neck skin, in the soft tissues of the scalp, orbit, and neck, and along the upper aerodigestive tract (UADT) mucosa. Typically, the spindle cell component is more haphazard than most true sarcomas, with any fascicle formation limited and irregular. The pathologic and clinical features can resolve this differential diagnosis. However, sarcomas in the head and neck area located at mucosal surfaces are extremely rare, and, when they do occur, an intervening fibrous layer usually separates the lesion from the overlying epithelium. However, if SpCC occurs intraosseously,366 its distinction from sarcomas with a spindle cell appearance may be extremely difficult or even impossible if immunohistochemistry or electron microscopy fail to reveal epithelial characteristics (Fig.