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Objectives Clear cell odontogenic carcinoma (CCOC) is a rare malignant odontogenic epithelial neoplasm composed mainly of clear cells. It was first described in early 1980s with great uncertainty of its behavior. Nearly 100 well-characterized cases have been reported to date with mean age at presentation of 54 years and female-to-male ratio of 1.6:1. It shows greater predilection for mandible compared to maxilla. Herein, we present a case of CCOC arising in maxilla and discuss the clinicopathologic presentation with emphasis on the potential differential diagnoses of other head and neck clear cell tumors (HNCCTs). Case Presentation A 68-year-old male presented with facial swelling and hard palate bleeding. CT scan revealed large destructive mass at the floor of right maxillary antrum with involvement of hard palate. Biopsy showed invasive carcinoma with squamous differentiation and focal keratinization. No evidence of lymph node metastasis was noted radiographically. The patient subsequently underwent total maxillectomy with complete resection of the tumor. Results Histologic sections revealed tumor arranged in lobular islands showing biphasic morphology including peripheral palisaded hyperchromatic basaloid cells and central clear to faintly eosinophilic cells with well-demarcated cell membranes. The intervening stroma was fibrous and showed hyalinization. The diagnosis of CCOC was made on the basis of tumor morphology in conjunction with EWSR1 gene rearrangement, which was detected by fluorescence in situ hybridization (FISH). Conclusion CCOC, although rare, should be considered in the differential diagnosis of tumors with a clear cell component. It can mimic a variety of HNCCTs, particularly clear cell variant of squamous cell carcinoma, clear cell tumors from minor salivary glands, or metastases from other sites. These tumors can be locally aggressive with a relatively high recurrence rate. Pathologists should be cognizant of this entity with other HNCCTs and the use of proper ancillary testing to avoid potential pitfalls.

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Inflammatory fibroid polyps are rare, benign, tumor-like lesions of the gastrointestinal tract. The lesion was first described by Vanek in 1949. Most frequently, they are localized in the gastric antrum, but can develop anywhere in the gastrointestinal tract. In the small intestine, these polyps cause obstruction-intussusception. Most IFPs are polypoid masses smaller than 5 cm, although sizes up to 20 cm have been reported. We report a case of a 56-year-old man with progressive midabdominal pain and tenderness in left lower quadrant. CT scan of abdomen and pelvis revealed an unusual, tubular, elongated mass causing mild partial obstruction and short segment intussusception. The patient underwent exploratory laparotomy and resection of the mass. Gross examination showed a large, solid, tan-white elongated tumor mass protruding into the small bowel lumen on one side and pushing the serosal surface on the other side. The large luminal portion of the protruding tumor measured 15.0 × 5.5 × 4.0 cm, and the extraluminal portion measured 5.5 × 4.0 cm. Total length of the tumor was 20.5 cm. Multiple sections showed a well-demarcated, nonencapsulated, fibrohistiocytic mass composed of widely spaced, bland, spindled and stellate-shaped cells emdedded in a collagenous fibromyxoid stroma with trapped collagen bundles, eosinophils, and few scattered plasma cells with foci of benign lymphoid aggregates. Immunoperoxidase stains were positive for CD34, vimentin, and CD68 (fibrohistiocytic marker) and negative for c-kit (CD117), actin, desmin, and S-100 protein. There was no histologic evidence of malignancy. The histopathologic features and the immunoperoxidase stains were consistent with a benign, nonneoplastic tumor-like mass, consistent with a giant inflammatory fibroid polyp-tumor-like mass (Vanek tumor). Inflammatory fibroid polyp, a rare, benign lesion of the gastrointestinal tract, arises from the submucosa. The lesion described in the present report is the largest inflammatory fibroid polyp reported to date; it occurred in the ileum, heretofore considered a rare location, and had a marked intraluminal and extraluminal component.

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