Hemangiopericytoma of the head and neck

Hemangiopericytoma/solitary fibrous tumor of the cranial base: a case series and literature review

Background

Hemangiopericytomas (HPCs) are uncommon soft tissue tumors. HPCs that grow in the cranial base are rare. Therefore, skull-base surgeons tend to overlook this disease. This study aimed to increase the awareness of HPCs by summarizing case data from our institution and related publications. We also aimed to contribute to the number of reported cases for future systematic reviews of HPCs.

Methods

This study included all patients who underwent surgery for HPC/solitary fibrous tumor (SFT) between August 2015 and August 2019. All surgeries were performed at Xiangya Hospital Central South University. We analyzed clinical characteristics, surgical highlights, treatment modalities, and outcomes.

Results

We included six patients, aged 32–64 years. Lesions were located in the parapharyngeal space in three patients, pterygopalatine fossa in two, and saddle area in one. All patients underwent nasal endoscopic endonasal surgery. In five patients, tumors involved the internal carotid artery (ICA). The exposure and protection of the ICA during surgery are challenging but critical to complete tumor removal. The 3-year overall survival(OS) rate was 66.7%.

Conclusions

HPC/SFTs are rare tumors of the cranial base that are prone to recurrence. Cranial base HPC/SFTs are often closely associated with the ICA. To our knowledge, this case series reports the largest number of cases of HPCs associated with the ICA. We believe that there is a strong relationship between patient prognosis and whether the tumor encircles the ICA and whether the tumor is completely resected. To confirm this suggestion, more cases are needed for further analysis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12893-022-01718-5.

Rare Diseases of the Nose, the Paranasal Sinuses, and the Anterior Skull Base

Due to their low incidence and thus resulting limited diagnostic criteria as well as therapeutic options, rare diseases of the nose, the paranasal sinuses, and the anterior skull base are a significant challenge. The value as of which a disease has to be considered as rare amounts to a maximum of 5 patients per 10 000 people. Within these diseases, however, there are extreme differences. Some rare or orphan diseases like for example the inverted papilloma belong to regularly diagnosed and treated diseases of larger departments of oto-rhino-laryngology whereas other rare diseases and malformations have only been described in less than 100 case reports worldwide. This fact emphasizes the necessity of bundling the available experience of diagnostics and therapy. The present article gives an overview about rare diseases of the nose, the paranasal sinuses, and the anterior skull base from the field of diseases/syndromes of the olfactory system, malformations of the nose and paranasal sinuses, ventilation and functional disorders as well as benign and malignant tumors. The classification and data on diagnostic and therapeutic options were established based on the current literature.

Sinonasal glomangiopericytoma: Is anything new?

More than 100 cases of sinonasal hemangiopericytoma have been reported in the literature, but only a handful of cases of nasal glomangiopericytoma. In this article, we report a case of a nasal glomangiopericytoma that was treated with endonasal surgical excision. We also attempt to clarify the confusion that attends to the nomenclature surrounding the terms glomangiopericytoma and hemangiopericytoma, which are often used interchangeably. Although glomangiopericytomas are histologically similar to sinonasal hemangiopericytomas, they sometimes behave in a different clinical manner. To further enhance our understanding of nasal glomangiopericytomas, more cases need to be reported. This may improve our ability to establish specific treatment modalities for this type of neoplasm and to predict clinical outcomes.

Treatment outcome and prognostic factors of head and neck hemangiopericytoma: meta-analysis

BACKGROUND

Head and neck hemangiopericytoma (HNHPC) is rare. Treatment outcome and specific prognostic factors were unexplored.

METHODS

A case meta-analysis, in which treatment and outcome data were available, was performed.

RESULTS

A total of 116 primary HNHPC cases were analyzed. Poor pathologic differentiation was associated with increased risk of tumor recurrence (odds ratio [OR] = 2.378; p = .005), metastasis (OR = 3.634; p = .011), and mortality (OR = 4.563; p = .002), whereas surgery was associated with decreased risk of tumor recurrence (OR = 0.109; p = .004). The tumor size >5.0 cm in diameter (hazard ratio [HR] = 6.391; p = .002), nonsurgical treatment (HR = 7.648; p = .000), and poor pathologic differentiation (HR = 1.705; p = .012) were the independent unfavorable prognostic factors for disease-free survival. Moreover, nonsurgical treatment (HR = 8.097; p = .002) and deep tumor location (HR = 4.074; p = .013) were independent adverse prognostic factors for overall survival (OS).

CONCLUSION

These results suggest a management emphasizing the surgical removal of the tumor as first-line treatment. Tumor size >5.0 cm, poor pathologic differentiation, deep tumor location, and nonsurgical treatment were independent adverse prognostic factors.

Sacro-anterior haemangiopericytoma: a case report

Haemangiopericytoma (HPC) is a rare vascular tumor with borderline malignancy, considerable histological variability, and unpredictable clinical and biological behavior. HPC can present a diagnostic challenge because of its indeterminate clinical, radiological, and pathological features. HPC generally presents in adulthood and is equally frequent in both sexes. HPC can arise in any site in the body as a slowly growing and painless mass. The precise cell type origin of HPC is uncertain. One third of HPCs occur in the head and neck areas. Exceptional cases of hemangioblastoma arising outside the head and neck areas have been reported, but little is known about their clinicopathologic and immunohistochemical features. This study reports on a case of a large sacro-anterior HPC in a 65-year-old male.

Primary sarcomas of the salivary glands: case series and literature review

BACKGROUND

Mesenchymal malignancies of salivary origin are rare and are histologically diverse. We reviewed our experience with these tumors, as well as the published literature, with an emphasis on treatment modalities and prognosis.

METHODS

We identified 17 patients treated for malignant mesenchymal cell tumors at The University of Texas MD Anderson Cancer Center between 1990 and 2007. We compared our results to the literature from January 1990 to July 2010.

RESULTS

Tumors were located primarily in the parotid gland and were primarily T1 tumors (<5 cm). All patients were treated with surgical resection, and 13 patients were given adjuvant therapy. Seven patients (41%) had recurrence, and 4 developed distant metastases. The overall 5-year and 10-year survival rates were 42% and 20%, respectively.

CONCLUSIONS

Our case series and literature review show that sarcomas of the salivary glands have a high rate of recurrence and are associated with a poor prognosis.

Haemangiopericytoma of the jaw

Haemangiopericytoma (HPC) is a vascular tumour which originates in the pericytes of vessels and therefore it may occur at any site, but it is very uncommon in the jaw. From January 2000 to December 2011, a retrospective analysis of nine consecutive patients with HPCJ was performed. There were five patients with a primary tumour and four patients with a recurrent tumour. Of the nine patients, eight were male and one female. Their ages ranged from 23 years to 51 years, with a median age of 38 years. The tumours were located in the mandible in six patients and in maxilla in three cases. The median course of disease was 7.6 months (range 2-12 months). All patients underwent surgery. Two patients had postoperative adjuvant radiotherapy, and two cases were given postoperative adjuvant chemotherapy. The median follow-up period was 49 months (10-101 months). One patient suffered from lumbar metastasis, while another case had metastasis at local and multiple distant sites, and eventually died. There was no local recurrence or metastasis in other seven cases. HPCJ are rare and the clinical characteristics are not specific. The first choice of treatment is radical surgery. Adjuvant radiotherapy may be effective to improve the prognosis of HPCJ.

Hemangiopericytoma of the Parapharyngeal Space

Hemangiopericytomas of the head and neck are rarely found in the parapharyngeal space. We report the case of a 53-year-old woman who presented with a globus sensation in her throat. Imaging detected a left submucosal oropharyngeal mass that extended into the prestyloid parapharyngeal space. The tumor was surgically excised en bloc. Histopathologic examination identified it as a hemangiopericytoma. We discuss the diagnosis and management of this rare entity.

A case of hemangiopericytoma of the soft palate with articulate disorder and dysphagia

We report a case of hemangiopericytoma of the soft palate of 60-year-old patient, who noticed a mass of the soft palate and experienced difficulty in speaking. We found a pediculate, hard, elastic mass measuring 38 mm (cross-sectional diameter). Computed tomography (CT) scans and dynamic magnetic resonance imaging (MRI) confirmed irregularly shaped mass and revealed a heterogeneous internal composition, consistent with vascular tumors. We excised the tumor under general anesthesia. Histopathological diagnosis was based on positive immunoreactivity of CD99 and vimentin and weak, positive staining of CD34. Three and half years following tumor excision, there is no recurrence or metastasis.

Management of sinonasal hemangiopericytomas: a systematic review

BACKGROUND

Hemangiopericytomas are typically found in soft-tissue, but only rarely found in the sinonasal tract. Sinonasal hemangiopericytomas have been reported mostly through case studies, and optimal treatment is considered surgical excision. Classically, open surgical methods of tumor extirpation have been considered standard of care. With the wider use of endoscopic methods, an updated systematic review in terms of treatment is warranted.

METHODS

Cases were identified using a MEDLINE and PubMed search. Relevant studies were identified, and data was extracted regarding patient demographics, presenting symptoms, tumor characteristics, treatment, and outcomes.

RESULTS

A total of 128 cases were collected from 56 articles, consisting of case reports and series. The most common presenting symptoms were epistaxis, nasal obstruction, and facial pain/swelling/pressure. Computed tomography (CT) and X-ray were the most common modes of imaging during diagnosis and operative planning. The tumor often occupied multiple locations in the sinonasal tract at initial presentation. Surgical resection was the mainstay of treatment in 126 of the 128 cases (98.4%), either through open resection or endoscopic techniques. Surgical removal resulted in no recurrence in 79.7% of the cases. The use of endoscopic techniques increased significantly in the past decade. This review found no significant difference in terms of recurrence between endoscopic and open treatment groups, age, gender, and unilocality vs multilocality of tumor.

CONCLUSION

Surgical management remains the mainstay of treatment for hemangiopericytomas. Endoscopic resection of these lesions has increased over the last few decades and has become a safe, viable, and reasonable alternative to open resection.

Systematic review of treatment and prognosis of sinonasal hemangiopericytoma

BACKGROUND

This study was undertaken to determine the recurrence rate for open and endoscopic surgery and the clinical prognosis of this sinonasal tumor.

METHODS

A systematic review of individual cases of sinonasal hemangiopericytoma was performed. A total of 97 articles were included in the study and reviewed to extract the relevant information about each case.

RESULTS

In all, 194 cases of sinonasal hemangiopericytoma were identified. There were 53 recurrences (27.3%), 6 tumor-related deaths (3.1%), and 4 cases of metastases (2.1%). There was no significant difference between rate of recurrence for endoscopic or open resection (p = .06). Incomplete excision was the most important predictor of recurrence (odds ratio = 11.50, 95% confidence interval 3.76-36.82, p < .001). Radiotherapy may be advantageous in cases of incomplete surgical resection (p = .03).

CONCLUSIONS

Complete excision is essential to minimize tumor recurrence and radiotherapy may decrease the rate of recurrence in the case of incomplete resection. Current evidence does not suggest that open resection is superior to endoscopic resection.

Select Neoplasms of the Sinonasal Tract

The sinonasal tract (SNT) includes the nasal cavity and paranasal sinuses (maxillary, ethmoid, frontal, and sphenoid) and may give rise to a variety of nonneoplastic and neoplastic proliferations, including benign and malignant neoplasms. The benign neoplasms of the SNT include epithelial neoplasms of surface epithelial origin, minor salivary gland origin, and mesenchymal origin. The spectrum of malignant neoplasms of the SNT includes epithelial malignancies, sinonasal undifferentiated carcinoma, malignant salivary gland neoplasms, neuroectodermal neoplasms, neuroendocrine neoplasms, melanocytic neoplasm, and sarcomas. This article concentrates on some of the more common types of benign and malignant neoplasms.

Concurrent Cochlear Implantation with Resection of Skull Base Hemangiopericytoma following Sudden Deafness in an Only Hearing Ear

A 72-year-old man with a known left acoustic neuroma, left-sided deafness, and a recently diagnosed right infratemporal fossa (ITF) hemangiopericytoma, presented with sudden deafness in his right ear. Imaging revealed right-sided skull base extension and a large intracranial tumor component. The patient underwent a frontotemporal crainiotomy with concomitant ITF approach. Complete tumor resection was possible, though invasion of the otic capsule was present. Immediately postresection, a cochlear implant (CI) was performed via a transmastoid approach. Full electrode insertion was achieved and confirmed by visualization through the dehiscent middle fossa floor. Mastoid obliteration was then performed with a free fat graft. Postoperative imaging confirmed complete tumor resection (Simpson grade I) and adequate CI placement. Follow-up magnetic resonance imaging was performed at 6 and 12 months, and no tumor recurrence was seen. Prior to CI activation, the patient was completely deaf bilaterally. At 18-month follow-up, however, excellent hearing was achieved with the right CI (16 of 22 electrodes active), and the patient is now conversational with no obvious deficit. His cognitive function is excellent, corresponding to preoperative status, and he is independent in his activities of daily living. Following adjuvant radiation, our patient remains disease free at 18 months.

Endoscopic, endonasal management of sinonasal haemangiopericytoma: 12-year experience

AIM

To report our experience with endoscopic, endonasal management of sinonasal haemangiopericytoma.

MATERIALS AND METHODS

Retrospective review of the medical records of 10 patients undergoing endoscopic, endonasal surgery for sinonasal haemangiopericytoma of the nose and paranasal sinuses, between 1997 and 2008.

RESULTS

Five men and five women were included. Their mean age at surgery was 59 years. All patients underwent endoscopic, endonasal resection of their tumour. Major post-operative complications were encountered in only one patient (stroke). Local recurrence was diagnosed in only one patient (10 per cent), who subsequently underwent a combined resection (endoscopic and external) with orbital exenteration.

CONCLUSIONS

Sinonasal haemangiopericytomas are rare tumours that are usually benign. The mainstay of treatment is wide surgical excision with free resection margins. Nowadays, the great majority of patients can be treated using a purely endoscopic, endonasal approach.

Haemangiopericytoma of the mandible

Haemangiopericytomas (HPCs) found in bony structures are rare sarcomas of vascular origin. Here, we report the case of a 41-year-old female with a HPC originating in the right ramus of the mandible. After tumour staging and biopsy for histological reference the tumour was surgically removed. The surgical technique is described and therapy options of these rare cases are discussed and compared with these cases already documented. To the best of our knowledge, this is the 6th case of mandibular HPC reported in the literature.

Lipomatous hemangiopericytoma of the skull base and parapharyngeal space

OBJECTIVE

To discuss the diagnosis and clinical management of lipomatous hemangiopericytoma.

STUDY DESIGN

Case report.

SETTING

Tertiary referral center.

PATIENT

A 36-year-old woman was encountered with symptoms of facial numbness, blurred vision, headache, and lightheadedness of 6 weeks' duration. Magnetic resonance imaging revealed a 5.0-cm mass in the right parapharyngeal space and skull base extending inferiorly to the level of the carotid bifurcation. The mass was consistent radiographically with a glomus jugulare tumor, and surgical extirpation was performed.

INTERVENTION

The patient underwent a transtemporal approach to the right posterior fossa and jugular foramen including mastoidectomy and isolation and preservation of Cranial Nerves VII, X, XI, and XII. Microscopic analysis of the mass revealed a highly cellular spindled mesenchymal tumor with a pericytoma pattern. Almost half of the mass displayed a mature lipomatous component. These findings were consistent with a lipomatous hemangiopericytoma.

RESULTS

The authors describe the first case of lipomatous hemangiopericytoma involving the skull base. This rare variant of the more common hemangiopericytoma has been described previously in the retroperitoneal and lower extremities. Although one case of lipomatous hemangiopericytoma has been described in the occipital region, this is the first report of this entity involving the parapharyngeal space, skull base, and jugular foramen.

CONCLUSION

The authors demonstrate that lipomatous hemangiopericytoma can occur in the parapharyngeal space and skull base. Once thought to be an aggressive variant, this tumor has an extremely low propensity for distant or local recurrence. Adjuvant therapies such as radiation and chemotherapeutic agents are reserved for recurrent or metastatic lesions.

A metastatic haemangiopericytoma of the floor of the mouth

A case of metastatic haemangiopericytoma in the floor of the mouth is described. Haemangiopericytoma is a relatively rare slow-growing vascular tumour with variable malignant potential. This tumour has been identified in almost every region of the body, but its occurrence in the oral cavity has been rarely reported. The rate of regional and distant metastasis of the tumour is low. This case, presented 12 years after initial surgery suggested the need for careful long-term follow-ups of patients with haemangiopericytoma.

Giant Hemangiopericytoma of Mandible

The hemangiopericytoma is a tumor of the pericytes. It represents 1% of vascular tumors. It is frequently located in inferior limbs, the pelvis, and the retroperitoneum. A painless mass of slow growth is main presentation. Imaging is not specific. Only microscopic and immunohistochemical findings can verify the lesion. The surgical treatment is elective. The search of the world medical literature revealed the publication of only four cases of hemangiopericytoma of the jaw. We present the case of a patient with a giant hemangiopericytoma that originated in the jaw. Studies showed an enormous mass and destruction of the right jaw. A right hemimandibulectomy including the condyle was performed. Mandibular reconstruction was performed with titanium plates with condyle and bone graft of the iliac crest; a piece of silastic with titanium mesh was placed in the temporomandibular articular fossa. Two years after surgery, good aesthetic and functional results were evident, and tumor recurrence was not observed.

Endoscopic Resection of Sinonasal Hemangiomas and Hemangiopericytomas

INTRODUCTION

Endoscopic resection of benign neoplasms, such as inverted papilloma, has been well described. There are limited case reports of endoscopic resection of benign vascular tumors, including hemangiomas, or those with low-grade malignant potential, such as hemangiopericytomas.

METHODS

Retrospective review of sinonasal hemangiomas and hemangiopericytomas resected endoscopically at a single tertiary-care facility.

RESULTS

Three hemangiomas and 3 hemangiopericytomas were resected endoscopically with no recurrences at a mean follow-up of 22 months. Four tumors involved the skull base; 2 of these underwent preoperative embolization. One patient had a CSF leak that occurred as the tumor was removed from the cribriform plate and that was successfully repaired intraoperatively. The average size of the tumors was 5.8 cm x 2.7 cm with all tumors at least 2.5 cm in greatest dimension by computed tomography or magnetic resonance imaging. The largest tumor was 12 cm in greatest dimension. An average of 8 intraoperative frozen section margins was taken around 5 tumors, with all margins of each tumor clear on final pathology. Patients included 4 males and 2 females with an average age of 47 years.

CONCLUSION

Large vascular neoplasms of the sinonasal cavity, such as hemangiomas and hemangiopericytomas, can be safely removed using endoscopic techniques. Although these patients have a limited follow-up, it is prudent to perform long-term endoscopic follow-up in order to detect recurrences regardless of resection technique.

Hemangiopericytoma of the infratemporal fossa: progression toward malignancy in a 30-year history

Hemangiopericytoma is a rare vascular tumor first described by Stout and Murray in 1942 and characterized by a proliferation of Zimmermann's pericytes, smooth muscle cells arranged around blood vessels. This tumor presents as a slowly enlarging painless mass. Diagnosis with certainty is often a difficult one because of the close likeness with other spindle cell tumors; it requires the help of immunohistochemical techniques and sometimes ultrastructural techniques. Only 15% of hemangiopericytomas are localized in the cervicofacial region; in particular, occurrence in the infratemporal fossa is an exceptional occurrence. In this article, we report an unusual case of recidivate hemangiopericytoma of the infratemporal fossa that has progressively assumed features of malignancy over 30 years. The hemangiopericytoma relapse potentiality is elevated, even when the histologic characteristics of the tumor indicate a low aggressivity, and therefore every hemangiopericytoma must be considered to have malignant potential. In conclusion, the unpredictable behavior of hemangiopericytoma requires a radical primary treatment to avoid the risk of relapses that always are frequent and aggressive.

Hämangioperizytom (extrapleuraler solitärer fibröser Tumor)

BACKGROUND

Hemangiopericytoma was first mentioned in 1942. It is a very uncommon potentially malignant vascular tumour which can occur at every site of the body. According to the WHO, most of the tumours formerly diagnosed as hemangiopericytomas are considered to be extrapleural solitary fibrous tumours. The diagnosis of "hemangiopericytoma" is now only determined if a constant histological picture of hemangiopericytoma is present. The tumour can lead to lymphogenous or hematogenous metastasis. The major location of occurrence is the cutis and subcutis. It originates from the pericytes of the vascular wall. This is reflected in its vascular character and therefore the hemangiopericytoma might clinically be mistaken for a hemangioma.

CASE REPORTS

Patient 1: 60 years, female; diagnosis: malignant suboccipital hemangiopericytoma; size: 4.9 x 4.5 x 4.2 cm; pT1bNXMX L0 V0 Pn0; stage IA; grading G1; R0.Patient 2: 38 years, male; diagnosis: benign hemangiopericytoma infraorbital left; size 1.5 x 1.5 x 1.5 cm.

DISCUSSION

Most often the hemangiopericytoma becomes clinically conspicuous as a slowly growing, painless swelling. The consistency ranges from soft to dense, and the color is greyish-blue. The slow and painless growth carries the danger of a clinically wrong diagnosis and thus delayed therapy. The histological diagnosis of hemangiopericytoma is determined by biopsy. Besides histology, MRI and angiography are methods that can be employed to diagnose hemangiopericytoma. The therapy of choice is the complete tumour-resection with a safety margin of 1 cm. In the case of an aggressive growth pattern, adjuvant postoperative radiotherapy is recommended. Until now there has been no documented specific therapy concept for managing incomplete resection and the occurrence of metastasis. There are reports about chemo- and radiotherapy either on their own or combined which evidence differing degrees of success. Lifelong monitoring is necessary because recrudescences and metastases can occur even decades later.

Vascular masses of the head and neck

The classification, clinical presentation, natural history and imaging appearances of vascular masses of the head and neck are reviewed. The radiological appearances of congenital vascular masses (infantile haemangiomas and other congenital vascular tumours, high-flow and low-flow vascular malformations), acquired vascular masses (benign and malignant tumours, non-neoplastic lesions) and other hypervascular masses are described and illustrated, together with consideration of image-guided interventions.

Haemangiopericytoma of the maxillary gingiva: report of a case

AIM

Haemangiopericytoma (HPC) represents approximately 3% of all tumours in the head and neck. This tumour is a soft tissue tumour derived from mesenchymal cells with pericytic differentiation. We present the clinicopathological findings of a case.

MATERIALS AND METHODS

A 69-year-old man was referred to our Department for a mass located on the right pre-molar maxillary gingiva; this mass caused problems during chewing, but was otherwise asymptomatic.

RESULTS

Clinical examination revealed a nodular, pink lesion, 3.5 cm in diameter, which was lined with normal mucosa. The lesion was mobile in relation to the deep and superficial tissues. Microscopic analysis of the neoplasm showed a vascular rich pattern, constituted by vessels covered with flat endothelium and surrounded by abundant spindly cells. On the basis of these histological and immunohistochemical findings, the final diagnosis was HPC.

CONCLUSIONS

HPC is an uncommon vascular tumour for which the biological behaviour is difficult to predict. In our patient, no recurrences or distant metastases were present at a 4 years follow-up.

[Perivascular neoplasms of skin and soft tissues. A review]

Perivascular neoplasms of skin and soft tissues comprise a group of benign and malignant mesenchymal neoplasms showing a perivascular myogenic differentiation. Whereas glomus tumour including its variants represents a clearly defined clinicopathological entity, the whole concept of haemangiopericytoma has been questioned in the last years, and no clear diagnostic criteria are established at the moment. Myopericytomas and myofibromas represent a morphological spectrum of perivascular spindle-shaped lesions. Infantile myofibroma/infantile myofibromatosis and solitary myofibroma of adults are characterized by a biphasic growth of mature, spindled, myofibroblastic cells and smaller, immature, mesenchymal cells associated with numerous haemangiopericytoma-like vessels. Benign and rare malignant myopericytomas of skin and soft tissues are characterized by a concentric, perivascular growth of plump spindled and round tumour cells staining positively for muscle actin, alpha-smooth muscle actin and more rarely for desmin. PEComas represent an enigmatic family of neoplasms composed of perivascular epithelioid, clear, and spindled tumour cells characterized by a coexpression of melanocytic and myogenic markers.

Sinonasal-type hemangiopericytoma: a clinicopathologic and immunophenotypic analysis of 104 cases showing perivascular myoid differentiation

Sinonasal-type hemangiopericytoma is an uncommon upper aerodigestive tract tumor of uncertain cellular differentiation. We report 104 cases of sinonasal-type hemangiopericytoma diagnosed between 1970 and 1995 from the files of the Armed Forces Institute of Pathology. There were 57 females and 47 males ranging in age from 5 to 86 years (mean 62.6 years). The most common clinical presentation was airway obstruction (n = 57) and/or epistaxis (n = 54), with symptoms averaging 10 months in duration. The tumors involved the nasal cavity alone (n = 47) or also a paranasal sinus (n = 26), were polypoid, and measured an average of 3.1 cm. Histologically, the tumors were submucosal and unencapsulated and showed a diffuse growth with fascicular (n = 37) to solid (n = 50) to focally whorled (n = 7) patterns. The tumor cells were uniform in appearance with minimal pleomorphism and had spindle-shaped (n = 82) to round/oval (n = 18) nuclei with vesicular to hyperchromatic chromatin and eosinophilic to amphophilic to clear-appearing cytoplasm with indistinct cell borders. Multinucleated (tumor) giant cells were identified in a minority of cases (n = 5). Mitotic figures were inconspicuous and necrosis was absent. The tumors were richly vascularized, including staghorn-appearing vessels that characteristically had prominent perivascular hyalinization (n = 92). An associated inflammatory cell infiltrate that included mast cells and eosinophils was noted in the majority of cases (n = 87). The immunohistochemical profile included reactivity with vimentin (98%), smooth muscle actin (92%), muscle specific actin (77%), factor XIIIa (78%), and laminin (52%). Surgery was the treatment of choice for all of the patients; adjunctive radiotherapy was given to four patients. Recurrences developed in 18 patients within 1-12 years from diagnosis. Ninety-seven patients were either alive (n = 51, mean 16.5 years) or dead (n = 46, mean 9.6 years) but free of disease. Four patients had disease at the last follow-up: three died with disease (mean 3.6 years) and one patient is alive with disease (28.3 years). Recurrent tumor (17.8%) can be managed by additional surgery. The majority of sinonasal-type hemangiopericytomas behave in a benign manner with excellent long-term prognosis (88% raw 5-year survival) following surgery alone. Sinonasal-type hemangiopericytomas have a characteristic light microscopic appearance with an immunophenotypic profile resembling that of glomus tumors.

Solitary fibrous tumor of the oral mucosa--morphological and immunohistochemical profile in the differential diagnosis with hemangiopericytoma

The objective was to investigate two cases of solitary fibrous tumor (SFT) of oral mucosa, emphasizing the differential diagnosis with one case of oral hemangiopericytoma (HPC), in terms of their morphological and immunohistochemical features. Solitary fibrous tumors showed cellularity and collagenization varying from area to area, focal perivascular hyalinization, scattered giant nuclei cells and abundant mast cells throughout the tumor. The hemangiopericytoma case exhibited thin-walled and dilated vessels lined with flat endothelial cells, identified by "staghorn appearance". Tumoral cells of solitary fibrous tumor exhibited immunohistochemical positivity for CD34, as well as endothelial cells. The hemangiopericytoma was positive only in endothelial cells. In solitary fibrous tumor, alpha-smooth muscle actin, h-caldesmon and laminin stained the wall vessels. In hemangiopericytoma, on the other hand, the wall vessels were positive only for laminin, which staining was also observed in perivascular tumoral cells. The morphological and immunohistochemical differences observed allowed us to infer these lesions constitute distinct entities.

Radiosensitive hemangiopericytoma in the soft palate

Hemangiopericytomas are uncommon neoplasms of vascular origin, and rarely arise in the pharynx. We report a case of a 78-year-old female with hemangiopericytoma in her soft palate exhibiting prominent radiosensitivity. Hemangiopericytomas are considered to be radioresistant and wide local excision is a treatment of choice, but their nature is widely variable. In treating aggressive hemangiopericytomas, radiation therapy can be selected.

Proliferation index as a prognostic marker in hemangiopericytoma of the head and neck

BACKGROUND

Hemangiopericytoma (HPC) of the head and neck is a rare neoplasm whose biologic behavior is difficult to predict by means of conventional histologic parameters.

METHODS

H & E-stained sections from 12 cases of HPC were reviewed. Proliferation index was assessed using an immunoperoxidase stain for MIB-1 (Ki-67).

RESULTS

The study group consisted of 4 adult men, 5 adult women, and 1 infant male. Necrosis, hypercellularity, and pleomorphism were found in 1, 5, and 6 case(s), respectively. The mitotic index per 10 high power fields varied from 0-1 to 15. Proliferation indices using MIB-1 ranged from 2.6% to 52.5%. Clinical follow-up revealed 3 cases with recurrence all possessing proliferation indices of approximately 10%.

CONCLUSIONS

Standard histomorphologic features may be inadequate predictors of clinical outcome. A proliferation index of 10% or greater may indicate a more aggressive subset of HPC of the head and neck.