Nodular fasciitis of the lip mucosa: a rare but clinically important entity

Oral Nodular Fasciitis: A Case Report in an Uncommon Location and Review of the Literature

Nodular fasciitis (NF) is a benign, self-limiting condition that is often misdiagnosed due to its resemblance to other lesions. Although NF is common, its occurrence in the oral cavity is rare and particularly challenging for both clinicians and pathologists. To date, no case has been reported in the retromolar area of the oral cavity. A 49-year-old male patient presented with a painless, rapidly growing, firm nodule in the right retromolar area. Histopathological examination revealed spindle cell proliferation with characteristics of NF and immunohistochemical analysis confirmed the diagnosis. The lesion was treated by conservative surgical excision, without recurrence at a one-year follow-up. In the current case, 54 cases of oral nodular fasciitis (ONF) have been documented. The majority of ONF-affected individuals are in their 40s, with a 1:1 male-to-female ratio. The buccal mucosa was the most commonly involved site followed by the tongue and labial mucosa. Histopathologically, the most prominent features were the proliferation of uniform spindle-shaped cells within a myxomatous and/or fibrotic background. A positive smooth muscle actin (SMA) stain was a consistent finding. Complete local excision remains the preferred treatment method, and no recurrences have been reported. This report underscores the importance of considering NF in the differential diagnosis of oral spindle cell lesions and emphasizes the need for a comprehensive evaluation to guide appropriate management.

A benign, low-grade myofibroblastic lesion mimicking a sarcoma

Benign myofibroblastic lesions can clinically and histologically be mistaken for sarcoma. Excessive and potentially disfiguring surgical treatment can be avoided by ruling out malignancy. We present the case of a low-grade, myofibroblastic lesion of the lip, which shows how detailed clinical examination rather than reliance on histopathological information alone helped to achieve this. Differential diagnoses of myofibroblastic lesions are also discussed.

Diagnosis and Differential Diagnosis of Desmoplastic Fibroblastoma by Clinical, Radiological, and Histopathological Analyses

Background:

Desmoplastic fibroblastoma (collagenous fibroma) is an uncommon benign soft-tissue tumor, rarely involving bone. It shares some overlapping features with other infiltrate tumors, such as desmoid-type fibromatosis, neurofibroma, and low-grade fibromyxoid sarcoma. The misdiagnosis may cause unnecessary surgical overtreatment, especially for those involving bone. In order to deepen the understanding of the diagnosis and differential diagnosis of desmoplastic fibroblastoma, we planned to analyze the clinical, radiological, and histopathological features and the outcome of desmoplastic fibroblastoma on the basis of case analysis and literature review.

Methods:

Sixteen cases were retrieved from the surgical pathology records from May 2011 to April 2016 in the Department of Pathology in Beijing Jishuitan Hospital. Formalin-fixed, paraffin-embedded specimens of 16 cases of desmoplastic fibroblastoma were collected. Hematoxylin and eosin stain and immunohistochemistry were used to observe the histological features of desmoplastic fibroblastoma of soft tissue and bone. The images for diagnosis obtained from the ultrasonic examination, X-ray, magnetic resonance imaging, and computed tomography were used to observe the radiological features. Related literatures were retrieved from the PubMed and CNKI databases.

Results:

Sixteen cases of desmoplastic fibroblastoma of soft tissue were located in the hand (n = 7), foot (n = 4), upper arm (n = 1), shoulder (n = 1), forearm (n = 2), and one case occurred in the proximal femur. Age ranged from 32 to 82 years (median age: 58 years). There were six females and ten males. Histologically, the lesions of soft tissue appeared as well-circumscribed masses with abundant collagenous matrix and low vascularity. Tumor cells were stellate- or spindle-shaped and uniformly distributed within the extracellular matrix. In five cases, the desmoplastic fibroblastoma were found to have infiltrated into the skeletal muscle tissue. In one case of desmoplastic fibroblastoma of bone, radiographs revealed osteolytically well-defined lesion. Immunohistochemistry stain showed that vimentin and smooth muscle actin were positive in all cases of desmoplastic fibroblastoma.

Conclusions:

Desmoplastic fibroblastoma (collagenous fibroma) has prominent clinical, histopathological, and radiological features. Before the differential diagnosis from other tumors is obtained by thorough analysis and comparison of the similar and different characteristics, the appropriate surgical management and accurate prognosis evaluation could not be delivered to the patient.

Oral nodular fasciitis – A case report with a diagnostic schema

Introduction: The spectrum of myofibroblastic lesions of the oral cavity ranges from reactive to benign to malignant lesions with overlapping histopathologic and immunohistologic characteristics posing a diagnostic dilemma. Observation: A 30-year-old male presented with a spontaneous swelling over the right lower buccal gingiva giving a clinical suspicion of a benign mesenchymal tumor. The lesion presented with a varied biphasic microscopic appearance that posed as a challenge for diagnosis. Commentaries: The incisional biopsy of the lesion showed a highly collagenous stroma with spindle-shaped cells, while the excision biopsy revealed myxoid and hyalinized stroma. A panel of markers comprising of SMA (smooth muscle actin). CD-34, β-Catenin, and Alcian blue stain was employed to arrive at a diagnosis. Conclusion: Most myofibroblastic lesions present with diverse histological appearance which warrants a thorough assessment of the cellular and stromal components for an accurate diagnosis.

Desmoplastic fibroblastoma (collagenous fibroma) of the oral cavity

Desmoplastic fibroblastoma is benign soft tissue tumor, with fibroblastic or myofibroblastic origin, that rarely occurs in oral cavity. We reported the case of a 56-year-old man who presented a tumor in the left mandibular alveolar ridge, with slow and asymptomatic growth, with no osseous involvement. The tumor was sessile with lobulated surface, covered by healthy mucosa with erythematous areas. The lesion was excised and specimens sent to histopathology and immunohistochemistry. Histopathological exam showed a non-encapsulated fibroblastic proliferation, characterized by myofibroblasts, spindle and stellate fibroblasts with large or oval nuclei and bi or tri nucleation, immersed in an abundant hypocellular dense collagen stroma. Tumor cells were positive for vimentin, HHF35, α-smooth muscle actin and factor XIIIa. The diagnosis of desmoplastic fibroblastoma was based in the clinical history of absence of trauma related to the growth in the alveolar ridge, associated with macroscopic, microscopic and immunohistochemical features. The patient is free-diseases by eight months.

KEY WORDS

Collagenous fibroma, desmoplastic fibroblastoma, neoplasm of connective and soft tissue.

Nodular Fasciitis of the Orofacial Region: An Uncommon Differential

Nodular fasciitis is a benign proliferative spindle-cell lesion that presents as a rapidly growing mass arising from the subcutaneous fascia, leading it to be erroneously diagnosed as a sarcoma. These lesions commonly present in individuals in their third to fifth decades of life with no definite gender predilection. They are frequently located on the extremities and the trunk and infrequently in the head and neck region. Lesions in the orofacial region are uncommon. We describe an interesting case of orofacial nodular fasciitis in a 21-year-old boy that essentially summarises the clinical features and management of this pseudosarcomatous reactive proliferative lesion. Clinicians and more so maxillofacial surgeons need to be aware of the distinctions between nodular fasciitis and its malignant mimic (sarcomas) in order to limit overtreatment and the resultant treatment-related morbidities.