SATB2 is frequently expressed in ossifying and non-ossifying peripheral oral fibroma of the gingival region but not in reactive fibromatous lesions from other intraoral sites

Ossifying fibroma from surgical excision to periodontal management: case report

Introduction and importance

Peripheral ossifying fibroma is one of the commonly occurring reactive benign lesions that occurs in the gingiva, predominantly in females, especially in the anterior maxillary region of young women and in pediatric patients. It causes unsatisfactory esthetics, difficulty in maintaining good oral hygiene and difficulty in mastication.The importance of this clinical case is to emphasize the interest of early management of the residual defect after the removal of the gum growth.

Case presentation

A 39-year-old female patient was referred to the clinical department of periodontology, with the chief complaint of bleeding gingiva, unsatisfactory esthetics and gum growth on the interproximal area in relation to left maxillary canine and premolar region, with the size ~2 cm×1.5 cm.

Clinical discussion

This article describes an atypical case of peripheral ossifying fibroma with the clinical, histopathologic, and radiographic features in the posterior maxilla in an adult female patient. Treatment consisted of complete surgical excision, gingival curettage, and management of keratinezed gingiva by utilizing laterally displaced flap. Clinical healing was satisfactory at 2 weeks, and excellent coverage of residual mucogingival defect with no evidence of recurrence was achieved 3 weeks postoperatively. The patient was satisfied with case resolution with a follow-up of 1 year.

Conclusion

Although surgical excision is the treatment of choice, sometimes it may induce residual soft tissue defect, which may further precipitate functional and esthetic discrepancies if not managed.

Immunohistochemical Characterization of Gingival Fibromas

PURPOSE

Gingival fibromas (GFs) are fibrous lesions of the gingiva that are not well defined in the literature. They are histologically similar to peripheral ossifying fibromas (POFs), both being characterized as cellular proliferations of dense fibrous tissue, with POFs differing in that they demonstrate foci of calcification. This study aims to expand upon the immunohistochemical characterization of GFs, and to confirm their osteoblastic phenotype.

METHODS

Formalin fixed, paraffin embedded GFs, POFs and fibroepithelial polyps (FEPs) of the gingiva were examined. Immunohistochemical staining was performed for special AT-rich sequence binding protein 2 (SATB2), runt-related transcription factor 2 (RUNX2), osteocalcin and alpha-smooth muscle actin (αSMA). Sections were evaluated by light microscopy and the immunohistochemical staining patterns were assigned immunoreactive scores (IRS) based on percentage of stained cells and intensity of staining.

RESULTS

GFs, POFs, and FEPs of the gingiva expressed osteoblastic markers SATB2, RUNX2 and osteocalcin. GFs and POFs expressed αSMA while FEPs of the gingiva did not. GFs and POFs had similar staining patterns of SATB2, RUNX2 and αSMA.

DISCUSSION

These findings demonstrate that GFs and POFs exhibit a similar immunohistochemical profile, and supports a theory that GFs are osteoblastic lesions possibly related to POFs.

Hepatocellular carcinomas can be Special AT-rich sequence-binding protein 2 positive: an important diagnostic pitfall

Special AT-rich sequence-binding protein 2 (SATB2) is a sensitive and specific marker for tumors originating with the colon and appendix. It is now commonly used in surgical pathology, while working up carcinomas of unknown primary. We had anecdotally encountered occasional hepatocellular carcinomas (HCCs) that were SATB2 positive. Immunohistochemical expression of SATB2 in HCC has not yet been examined in detail. In this study, we evaluated SATB2 expression in 46 HCCs. Nineteen (41%) of 46 HCCs were positive for SATB2. SATB2 expression in HCCs was more commonly seen in poorly differentiated tumors (11 of 13 cases, 85%) than well and moderately differentiated tumors (8 of 33 cases, 24%), p value = 0.0001. No other statistically significant correlations were observed (p > 0.05). There were no other statistically significant correlations between SATB2 expression and age, gender, background liver disease, and cirrhosis (p > 0.05). Results of our study show that a significant subset (41%) of HCCs can be SATB2 positive. Awareness of this phenomenon is important as SATB2 expression in a liver tumor does not completely exclude a diagnosis of HCC.