Leiomyosarcomas of the oral tissues: clinicopathologic analysis of 50 cases

A Rare Lesion at Rare Location: A Surgeon's Enigma

Leiomyosarcoma of palate is a rare malignant spindle cell tumour in oral cavity. It is often misdiagnosed with other benign lesions like nodular fasciitis, clinical and histological similarity of rapid growth, rich cellularity, as the pathogenesis is unknown, which can make diagnosis and management challenging. The non-specific clinical, radiologic and pathological presentation of spindle cell tumours causes diagnostic difficulty due to similarities to granulation tissue, benign or malignant lesions in histologic and imaging features. Nevertheless, differentiation is important because the prognosis and treatment varies according to the type of tumor. NF is frequently evaluated by biopsy and also immunohistochemistry (IHC) which is very essential in cases of non-regressing lesions after biopsy. The present case report highlights the clinical and histopathologic challenges in a rare case of nodular fasciitis in the palate which initially diagnosed as granulation tissue and later confirmed as Grade l leiomyosarcoma on IHC.

Invasive leiomyosarcoma involving the tongue of an Arabian mare

A 10 year-old endurance Arabian mare was presented with an invasive, firm, multilobulated mass at the left ventral face of the tongue. The mare had a history of four months of ptyalism, dysphagia, severe halitosis, and dysmastication. The Evaluation of the horse included physical and oral examination, complete blood count and serum biochemistry profile, computed tomography evaluation of the head, and histopathology of the mass. The computerized tomography (CT) head scan showed the homogeneous mass in the oral cavity confirming the degree of invasion on the tongue, as well as a small mineral focus at the left dorsal mandibular border and increased density of the submandibular lymph nodes. At necropsy, gross findings in the oral cavity revealed an irregular, nodular and partially ulcerated mass at the level of the body of the tongue in the ventral aspect, with a size of approximately 10 × 15 × 8 cm. Histologically, the tongue revealed a neoplastic process of mesenchymal muscle origin. The tumor cells showed distinctive morphological and architectural patterns in some areas. An immunohistochemistry panel was done yielding a positive reaction for Calponin and Desmin, confirming diagnostics of as a soft tissue leiomyosarcoma in the tongue. Immunohistochemistry results, in combination with histopathologic morphology, were suggestive of a leiomyosarcoma originating in the perivascular wall tissue. Oral leiomyosarcoma are very rare in veterinary medicine, and to the authors' knowledge, this is the first case report to utilize histopathology, immunohistochemistry and imaginology to describe oral leiomyosarcoma in a horse.

Leiomyoma and Leiomyosarcoma (Primary and Metastatic) of the Oral and Maxillofacial Region: A Clinicopathological and Immunohistochemical Study of 27 Cases

Smooth muscle neoplasms represent an important group of lesions which is rare in the oral cavity. Leiomyoma (LM) is benign smooth muscle/pericytic tumor usually presenting as non-aggressive neoplasm, while leiomyosarcoma (LMS) represents its malignant counterpart. The rarity of these lesions, together with its unspecific clinical presentation and a variable histopathological appearance, lead to a broad list of differential diagnoses, hampering their diagnoses. Therefore, in this study we describe the clinical and microscopic features of a series of oral and maxillofacial LMs and LMSs. A retrospective search from 2000 to 2019 was performed and all cases diagnosed as LM and LMS affecting the oral cavity and gnathic bones were retrieved. Clinical and demographic data were obtained from the patients' pathology records, while microscopic features and immunohistochemistry were reviewed and completed when necessary to confirm the diagnoses. Twenty-two LMs and five LMSs were obtained. In the LM group, males predominated, with a mean age of 45.7 years. The upper lip was the most affected site, and 18 cases were classified as angioleiomyomas and four as solid LM. In the LMS group, females predominated, with a mean age of 47.6 years. The mandible was the most affected site. Diffuse proliferation of spindle cells, with necrosis and mitotic figures, were frequent microscopic findings. LMs and LMSs were positive for α-smooth muscle actin, HHF-35 and h-caldesmon. In conclusion, oral LM/LMS are uncommon neoplasms with the latter usually presenting as metastatic disease. H&E evaluation may be very suggestive of oral LMs, but h-caldesmon staining is strongly recommended to confirm LMS diagnosis.

Pediatric leiomyoma of the oral cavity: A rare entity

Leiomyoma is a benign smooth muscle tumor that frequently occurs in the uterine myometrium of the uterus and gastrointestinal tract rarely but seldom encountered in the oral cavity, particularly in children. Its occurrence in the oral cavity is considered rare probably because of the scarcity of smooth muscle tissue in the oral cavity. The frequently affected anatomical areas intraorally are lips, palate and tongue. The purpose of this case report is to put forth a rare case of oral leiomyoma in a 10-year-old girl child involving the retromolar region.

Leiomyosarcoma of the jaw: case series

Objectives

Leiomyosarcoma is a malignant neoplasm that affects smooth muscle tissue and it is very rare in the field of oral and maxillofcial surgery. The purpose of this study was to obtain information on diagnosis of and treatment methods for leiomyosarcoma by retrospectively reviewing of the cases.

Patients and Methods

The study included nine patients who were diagnosed with leiomyosarcoma in the Department of Oral and Maxillofacial Surgery at Seoul National University Dental Hospital. The subjects were analyzed with respect to sex, age, clinical features, primary site of disease, treatment method, recurrence, and metastasis.

Results

Particular clinical features included pain, edema, mouth-opening limitations, dysesthesia, and enlarged lymph nodes. All cases except one were surgically treated, and recurrence was found in two cases. Four of nine patients were followed up without recurrence and one patient underwent additional surgery due to recurrence.

Conclusion

In our case series, notable symptoms included pain, edema, mouth-opening limitations, and dysesthesia; however, it was difficult to label these as specific symptoms of leiomyosarcoma. Considering the aggressive characteristics of the disease and poor prognosis, surgical treatment is necessary with careful consideration of postoperative radiotherapy and chemotherapy.

Primary oral leiomyosarcoma: A systematic review and update

The aim of this systematic review was to address the clinicopathologic inconsistencies noted with primary oral leiomyosarcoma in the literature by amassing the available data published into a comprehensive analysis. Eligibility criteria included publications of cases with dedicated immunohistochemical work-up along with radiographs to evaluate location. Based on these criteria, the systematic review compiled 29 cases. Four primary location sites were identified in the reported cases: soft tissue presentation only, soft tissue with bony involvement, bony involvement only, and bony involvement with a soft tissue component. The majority of primary oral leiomyosarcoma cases reviewed showed a soft tissue predilection, which is in contrast to prior reports of jawbones being the most common site. In addition, there was an improved 5-year survival rate for primary oral leiomyosarcoma limited to the oral cavity and gnathic bones without extension into paranasal sinuses.

Unusual presentation of metastatic leiomyosarcoma-right forearm swelling

Leiomyosarcoma (LMS) is a rare smooth muscle connective tissue tumour accounting for around 11% of soft-tissue sarcomas (Ducimetiere F, Lurkin A, Ranchere-Vince D, Decouvelaere AV, Péoc’h M, Istier L et al. Incidence of sarcoma histotypes and molecular subtypes in a prospective epidemiological study with central pathology review and molecular testing. PLoS One 2011;6:e20294). LMS are highly unpredictable tumours that can present at any site in the body, most commonly in the uterus, stomach, small intestine and retroperitoneum. There are few published case reports within the literature on the metastatic spread of LMS to skeletal muscle. We present an unusual presentation of metastatic Leiomyosarcoma in the right forearm of a 71-year-old male treated with limb-sparing surgical excision. This case report demonstrates the unusual and unpredictable nature of metastatic LMS presentation, which poses difficulty in diagnosis and management.

Sarcomas of the Oral and Maxillofacial Region: Analysis of 26 Cases with Emphasis on Diagnostic Challenges

Sarcomas of the Oral and Maxillofacial Region (SOMR) are rare lesions which pose diagnostic and management challenges. We analyzed 26 cases of SOMR with respect to clinical presentation, histopathological subtype, treatment modalities, recurrence, and treatment outcome. In our series, Osteosarcoma (OS) was the most common type of sarcoma (7 cases), followed by 5 cases of Ewing's Sarcoma (ES), 3 cases each of Chondrosarcoma (CS) and Leiomyosarcoma (LMS), 2 cases each of Malignant Peripheral Nerve Sheath Tumor (MPNST), Pleomorphic Undifferentiated Sarcoma (PUS), Myeloid Sarcoma (MS)and Rhabdomyosarcoma (RMS). Surgery was the primary treatment modality in most cases and was combined with adjuvant chemo/ radiotherapy in few cases. 24 of the 26 cases were followed up for an average period of 40.67 months. Adverse disease outcomes like recurrence were seen in 2 cases whereas death due to the disease was reported in 7 cases. In view of the diagnostic challenges faced in SOMRs, it appears practical to stress on the underlying genetic aspects of the disease process rather than histological subtyping to improve disease outcome.

Primary Leiomyosarcoma of the Buccal Mucosa: Report of a Case and Review of the Literature

This clinicopathologic study of primary oral leiomyosarcoma of the buccal mucosa involves a literature review of 15 cases with the addition of our report of a case. The demographic details, tumor size, treatment and outcome are documented for all the cases. In addition, this review examines the histologic features of leiomyosarcoma while noting that differentiation from other spindle cell tumors can be challenging, underscoring the necessity of an immunohistochemical work up for an accurate diagnosis. The unpredictability of the clinical behavior of these aggressive tumors requires, at the very least, wide local surgical excision and prolonged follow up.

Gingival Leiomyosarcoma in a Young Woman: Case report and literature review

Leiomyosarcoma (LMS) is a rare mesenchymal malignancy, of which 3-10% of cases occur in the head and neck region. We report a 22-year-old woman who was referred to the University Hospital of Siena, Italy, in 2016 with an ostensibly benign asymptomatic lump on the mandibular gingiva. The lesion grew rapidly, causing otalgia in the right ear. An excisional biopsy was performed and primary LMS was diagnosed histologically. Subsequently, the patient underwent radical re-excision of the perilesional mucosa, a partial bone resection and the extraction of four teeth. No recurrences or metastases were detectable at a 20-month follow-up. This report discusses the differential diagnosis of LMS with regards to other benign and malignant lesions and reviews the recent literature on primary and secondary oral LMS. Due to its innocuous clinical features-including its asymptomatic nature and presentation at a young age-this aggressive malignancy can go undetected; therefore, an early histopathological diagnosis is crucial.

Primary Leiomyosarcoma of the Mandibular Alveolar Mucosa of a 12-Year-Old Child from Ethiopia: A Case Report

Leiomyosarcomas (LMSs) are rare malignant mesenchymal tumors which show smooth-muscle differentiation. Most LMSs involving the oral tissues primarily affect the maxillary sinus, the maxillary or mandibular bone. We present a case of LMS of the mandibular alveolar mucosa, arising in a 12-year-old male child from Ethiopia. A malignant spindle cell-like neoplasm was diagnosed on clinical and radiographic findings as well as on incisional biopsy. The tumor was resected with wide margins. The following histopathologic examination with additional immunohistochemical studies secured the diagnosis LMS. Microscopically, the spindle-shaped tumor cells were arranged in an interlacing fascicular pattern and contained oval to elongated, blunt-ended (cigar-shaped) nuclei. The immunohistochemical examination showed immunoreactive tumor cells for vimentin, actin, desmin, and H-caldesmon, which is pathognomonic for LMS. Immunohistochemical studies are mandatory to differentiate the LMS from other similar spindle cell neoplastic lesions. Radical resection with safety margins and a lifelong periodic follow-up has to be recommended.

Leiomyosarcoma of the parapharyngeal space: a very rare entity

Leiomyosarcoma of the head and neck is very rare, as only about 100 cases have been reported; of these, only 3 cases have been previously reported in the parapharyngeal space. We report the fourth such case, and we review the features of this entity. The patient was an 84-year-old woman who presented to the emergency department for treatment of an 18-month history of right-sided headache, a 6-month history of right-sided hearing loss and nasal obstruction, and a 2-month history of dysphagia. Physical examination revealed a bulge in the right side of the soft palate and the right lateral nasopharyngeal wall and complete obstruction of the right eustachian tube. Indirect laryngoscopy detected a bulge in the right lateral hypopharyngeal wall. Otoscopy revealed otitis media with effusion in the right ear. Imaging demonstrated a space-occupying lesion in the right parapharyngeal space that extended from the base of the skull to the level of the hypopharynx. Biopsy and histology identified the mass as a leiomyosarcoma. Metastasis to the brain was discovered shortly thereafter, and the patient died 10 months later. The unusual presentation of head and neck leiomyosarcoma requires a high index of suspicion and appropriate diagnostic imaging. Surgical excision is the recommended treatment when feasible; chemoradiotherapy does not appear to affect disease progression.

Tonsillar leiomyosarcoma

Leiomyosarcomas of the head and neck is an extremely rare entity that because of its infrequency has been associated with both delayed diagnosis and misdiagnosis. Sinonasal tract is the most common site in this region. The overall prognosis is poor. It is necessary for appropriate immunohistochemical investigation for accurate diagnosis. Tonsillar leiomyosarcoma presented only 1 case in the English-language literature (PubMed, Ovid, and Proquest databases). We report a second case of leiomyosarcoma arising in the tonsil in a 38-year-old woman.

LEVEL OF EVIDENCE

Level IV therapeutic study.

Primary leiomyosarcoma of the maxilla: An investigative loom-report of a challenging case and review of literature

Leiomyosarcoma (LMS) is a malignant neoplasm composed of cells showing distinct smooth muscle features. Majority of the tumors are located in the retroperitoneum, including the pelvis and the uterus but are rare in the oral and pharyngeal region. Intraorally, they are present as painless, lobulated, fixed masses of the submucosal tissues in middle-aged or older individuals. Lesions are usually slow growing and are less than 2 cm in diameter at the time of diagnosis. Here we report the clinico-pathological findings of a case of primary LMS of the maxilla in 63-year-old male patient with an emphasis on the judicious use of ancillary diagnostic modalities to arrive at a definitive diagnosis.

Solitary myofibroma of the mandible: an immunohistochemical and ultrastructural study with a review of the literature

A solitary myofibroma (MF) is an unusual spindle cell neoplasm that usually arises in the soft tissue, skin, or bone of the head and neck region in infancy. We report an extremely rare case of MF of the mandible in an 18-year-old Japanese woman together with the conventional histologic, immunohistochemical, and electron microscopic findings. The tumor was well circumscribed and composed of fibroblast-like or myofibroblast-like spindle cells. On immunohistochemical evaluation the tumor cells were positive for vimentin, α-smooth muscle actin, HHF-35, and calponin, but negative for neurogenic antigens and markers for vascular endothelial cells. The Ki-67 labeling index was 10 % and the p53 labeling index was 10 %. Ultrastructural examination revealed smooth muscle cell differentiation. The patient was treated by surgical resection and underwent follow-up without any signs of recurrence. MF presents a wide range of differential diagnosis, including benign and malignant neoplasms. Therefore, accurate diagnosis may avoid an unnecessarily aggressive therapy.

Melanotic and non-melanotic malignancies of the face and external ear - A review of current treatment concepts and future options

Skin has the highest incidence and variety of tumors of all organs. Its structure is of great complexity, and every component has the potential to originate a skin neoplasm (SN). Because of its exposed nature, skin is vulnerable to carcinogenic stimuli such as UV radiation. Various entities can cause SN. Nonmelanotic skin cancers (NMSC) are the most common of all cancers, with over one million cases diagnosed annually in the US. Basal cell carcinoma (BCC) accounts for approximately 80% of all NMSC, most of the remaining 20% being squamous cell carcinoma (SCC). The skin of the head and neck is the most common site for tumors, accounting for more than 80% of all NMSC. BCC, SCC, and malignant melanomas (MM) represent 85-90% of all SN. Merkel cell tumors (MCC), lymphoepithelioma-like carcinomas of the skin (LELCS), dermato-fibro-sarcomas, leiomyosarkomas, and Kaposi-sarcomas are less frequent in the facial skin region and the external ear. Based on data from the German Federal Cancer Registry (2003/2004), 140,000 people in Germany were affected by SN (100,000 BCC, 22,000 SCC, 22,000 MM). This number increases considerably if malignant precursors, such as actinic keratosis, are included. Each year, the frequency of SN diagnosis rises by 3-7%. Among all known malignant tumors, MM exhibits the highest rate of increase in incidence. In the past, SN was primarily diagnosed in people aged 50 years or older. However, recently, the risk for developing SN has shifted, and younger people are also affected. Early diagnosis is significantly correlated with prognosis. Resection of SN creates defects that must be closed with local or microvascular flaps to avoid functional disturbing scar formation and deflection of the nose, eyelids, or lips. All therapeutic strategies for SN, the current standard for adjuvant and systemic treatment, and the management of the increasing number of patients under permanent blood thinner medication are described with regard to the treatment of SN.

Leimyosarcoma of the buccal mucosa and review of literature

Leiomyosarcoma (LMS) is an uncommon malignant spindle cell tumor of the head and neck region. The occurrence is particularly rare in the buccal mucosa of the oral cavity. It is a rapidly growing tumor with aggressive behavior and poor prognosis. Method: This article presents a rare case of primary leimyosarcoma of the buccal mucosa in a 35 year old female and retrospective analysis of primary oral LMS published in the English literature since past 20 years is done. Diagnosis was confirmed by immunohistochemistry profile showing positivity for vimentin, smooth muscle actin (SMA), high proliferative index displayed by Ki-67, focal positivity for pan-CK and negativity for S-100. Conclusion: Based on the presence of malignant spindle cells showing positivity for vimentin and SMA, a diagnosis of leiomyosarcoma was made.

Intraosseous leiomyosarcoma of the mandible: a case report

Leiomyosarcomas are rare smooth muscle tumors that can occur anywhere in the body. These tumors rarely occur in the head and neck owing to the limited amount of smooth muscle in the region. The clinical diagnosis of leiomyosarcoma is challenging because of the nonspecific presentation of the disease. The most definitive diagnosis is based on tissue biopsy or surgical resection and histopathologic confirmation. A case of intraosseous leiomyosarcoma of the mandible and a review of the literature are presented.

Primary and secondary leiomyosarcoma of the oral and perioral region--clinicopathological and immunohistochemical analysis of a rare entity with a review of the literature

PURPOSE

Leiomyosarcoma (LMS) rarely occurs in the head and neck region. These tumors present with a wide range of clinical features, so the diagnosis is predicated on conventional microscopic findings coupled with immunohistochemical analysis.

PATIENTS AND METHODS

Clinical and histologic data of 7 patients with LMS of the head and neck were recorded retrospectively. In addition to routine immunohistochemistry, staining for cell cycle regulator proteins p16 and p21 was performed.

RESULTS

Five LMSs (4 intraoral, 1 dermal cheek) occurred primarily in the oral and perioral region. Two LMSs (parietal and sinonasal) were diagnosed as metastases originating from the uterus and pelvis. Treatment of the primary LMSs consisted of radical tumor resection with clear margins. Distant metastases from LMSs were irradiated or excised as palliative treatment. Three of 5 patients (60%) with primarily excised LMS developed recurrence after an average of 7 months, with lung metastases occurring after 17 months. In 1 patient, cervical lymph node metastases were detected after 10 months. Of all patients, 5 died after an average survival period of 2.4 years. The mean survival period of the 5 patients with primary LMS of the head and neck was 3.3 years. All tumors were positive for vimentin and α-smooth muscle actin, with 57% of tumors showing positive nuclear expression of p16 and 71% of p21. Lack of p16 nuclear expression was associated with a shorter mean survival time (1.3 vs 4.3 yr for p16 positivity).

CONCLUSION

Lung and cervical lymph node metastases often occur in LMS of the head and neck. Presurgical staging, including gynecologic examination, whole-body computed tomography, and sometimes positron-emission or computed tomography, to rule out LMS metastasis is mandatory. Surgical resection of the tumor should be given top priority. Lack of p16 reactivity may have a prognostic value for LMS because it was related to a trend toward poorer survival.

Leiomyosarcomas of the oral cavity: report of a radiation-associated and a metastatic case

BACKGROUND

Leiomyosarcoma is rare in the oral cavity, where it may arise as primary, radiation-associated, or metastatic tumor. This article reports two cases of oral leiomyosarcoma, discussing the range of clinicopathological features and the significance of these presentations.

CASE REPORT

One case is a radiation-associated leiomyosarcoma arising in the tongue of a 71-year-old male occurring 22 years after radiation therapy for tonsil squamous cell carcinoma that was surgically treated. The other one is a mandible metastasis from a retroperitoneal widespread leiomyosarcoma in a 69-year-old man, who was treated by surgery and chemotherapy but died from the disease.

DISCUSSION

Post-radiotherapy sarcomas of the oral cavity and oral metastasis from soft tissue sarcomas are very uncommon, but based on patient's clinical history, they should be considered by oral health care providers in order to allow an early diagnosis and proper and timely management. Finally, to the best of our knowledge, this seems to be the first reported case of tongue leiomyosarcoma arising in a previously irradiated field.

Primary oral leiomyosarcoma: a retrospective clinical analysis of 20 cases

PURPOSE

As a review and clinical analysis of primary oral leiomyosarcoma (LMS) cases in West China stomatology Hospital in the past 37 years, this study provides demographic, therapeutic and prognostic information of this rare tumor.

PATIENTS AND METHODS

In our study, 20 cases of primary oral LMS treated between 1972 and 2008 in West China Stomatology Hospital were analyzed retrospectively. A thorough review of clinical records was carried out and potential indicators of survival were analyzed.

RESULTS

The most common symptom of oral LMS presented as a painless mass. The median age of patients was 37 years, and the peak incidence age of this tumor was in the 2nd and 5th decades. There was no predilection of gender, and the male-to-female ratio was 11:9. The most frequently occurring site of oral leiomysarcoma was the jawbones. The prognosis of this tumor was poor as a result of the high local recurrence and the estimated 2 year survival was 17.6%. The bony involvement and method of therapy was observed to have an influence on the prognosis and survival of this tumor (P < 0.05).

CONCLUSION

There was a predilection site of jawbones for oral LMS, and bony involvement was a potential indicator suggesting a poorer prognosis. The recommended method of therapy on this tumor was aggressive, radical surgical resection; however, adjuvant radiotherapy and chemotherapy may also have a beneficial effect.

Oral myofibromas: report of two cases and review of clinical and histopathologic differential diagnosis

Myofibroma is a benign mesenchymal neoplasm composed of myofibroblasts which has been described with different synonyms since the first report in 1951. It may show clinical and histologic features that may be misinterpreted as a malignancy. We describe 2 cases of oral myofibromas affecting infants; the first one showed a rapid growth with teeth displacement and ulceration; the second one presented a relatively slow growth with an indolent course. Differential diagnosis included benign and malignant mesenchymal neoplasms, salivary gland tumors, and reactive processes. Microscopic analysis of both lesions revealed a spindle cell tumor with immunoreactivity for vimentin, muscle-specific actin, and specific smooth muscle isoform alpha-actin, rendering the diagnoses of myofibroma. The patients were treated with surgical excision, and both are in follow-up without any signs of recurrence. Myofibroma presents a wide range of differential diagnosis, including benign and malignant neoplasms. Therefore, accurate diagnosis may avoid an unnecessary aggressive therapy.

Oral leiomyosarcomas: report of two cases with immunohistochemical profile

Leiomyosarcoma of the oral cavity is a very rare tumor associated with aggressive clinical behavior and low survival. In this paper, we report 2 cases of leiomyosarcoma, affecting the gingival mucosa of a 54-year-old female and the maxillary bone of a 63-year-old male. Histologically, the tumors were composed of variably oriented fascicles of spindle-shaped cells with cigar-shaped nuclei and eosinophilic cytoplasm. The lesions were treated by surgical resection. Immunoreactivity to anti-vimentin, anti-smooth muscle actin, anti-desmin, anti-laminin, and anti-muscle-specific actin antibodies were found; conversely, the tumor cells were negative for anti-S100 and AE1/AE3 proteins. This report emphasizes the role of immunohistochemical study for correct diagnosis of leiomyosarcoma.

Primary oral leiomyosarcoma: a clinico-pathologic study and analysis of prognostic factors

This clinico-pathologic study of primary oral leiomyosarcomas and analysis of potential prognostic factors involved a literature review of 64 cases and a report of four cases treated in the authors' unit. The demographic details, clinical presentation, diagnosis, treatment and outcome were documented for the whole group and clinico-pathologic variables analysed to detect potential prognostic factors. The most common presentation was that of a painless mass, with peak incidence in the 6th decade and a slight male predeliction (M:F=1.3:1). The maxilla was the most frequently involved site, followed by the mandible and tongue. Surgical excision was most commonly employed with radiotherapy and chemotherapy being reserved for recurrent and metastatic tumours. Local recurrence (34%) and metastasis (35%) were not uncommon and occurred most frequently to the lungs and regional lymph nodes (15%). Age, sex, size and mitotic index were not statistically related to recurrence or metastasis. Site (P=0.0125) was a predictor of metastasis. Metastasis (P=0.010) and lesions involving the maxilla and mandible (P=0.019) were associated with decreased survival. The estimated 5 year survival was 55% for the whole group and 43% and 19% for patients with bony involvement and metastasis respectively.