SKULL BASE SURGERY/VOLUME 5, NUMBER 3 JULY 1995

CASE REPORT

Sinonasal Hemangiopericytoma:Case Report and Literature Review

Jon K. Thiringer, L.C.D.R., M.C., U.S.N.R.,Peter D. Costantino, M.D.,

and Glen Houston, Col., D.C., U.S.A.F.

Hemangiopericytoma (HPC) is an unusual vasculartumor derived from pericytes.12 These cells can be foundsurrounding all capillaries and are thought to be immaturesmooth muscle derived from mesenchyme. Pericytes addstructural support to the capillaries while playing a role incapillary blood flow regulation. Approximately 1% of allvasoformative neoplasms are HPC, with 15 to 25% pre-senting in the head and neck.3'4 Of those occurring in thehead and neck, approximately 50% involve the paranasalsinuses and nasal cavity. Other sites of predilection are thesoft tissues of the scalp, face, and neck, parotid gland,orbit, and rarely the salivary glands and larynx. SinceHPC is derived from capillary pericytes, its theoreticalsite of origin can be virtually anywhere in the body.Indeed, HPC has been reported in a wide variety of tissuesoutside the head and neck, most frequently occurring inskeletal muscle and the retroperitoneum.3,5 As will bediscussed in this report, the site of lesion has a significant

bearing on clinical behavior and perhaps on histologiccharacter as well.

CASE REPORT

A 58-year-old Caucasian woman with a past medicalhistory significant for coronary artery disease, hyperten-sion, gout, follicular thyroid carcinoma, cutaneous mela-noma, degenerative joint disease, and "chronic sinusitis"presented to another institution in April 1992 complainingof worsening "sinus headache," epistaxis, and left perior-bital and malar pressure. Head and neck examination wasremarkable only for a left posterior "rubbery" nasalmass. There was no cervical adenopathy, and cranialnerves were intact. Computed tomography (CT) scan inApril 1992 revealed a mass in the left sphenoid sinus andmagnetic resonance imaging (MRI) in May 1992 indi-

Skull Base Surgery, Volume 5, Number 3, July 1995 Department of Otolaryngology Head and Neck Surgery and Oral Pathology, Wilford HallMedical Center, Lackland AFB, Texas Presented at the 1994 Joint Annual Meeting of the German and North American Skull Base Societies,Orlando, Florida The opinions expressed in this article are those of the authors and do not necessarily represent those ofthe United States Air Force,United States Navy, the Department ofDefence, or other departments ofthe United States Government. Reprint requests: Dr. Costantino, Section ofHead and Neck Surgical Oncology, Loyola University Cancer Center, 2160 South First Ave., Maywood, IL 60153 Copyright X) 1995 by ThiemeMedical Publishers, Inc., 381 Park Avenue South, New York, NY 10016. All rights reserved. 185

SKULL BASE SURGERYNOLUME 5, NUMBER 3 JULY 1995

Figure 1. Low-power micrographof the hemangiopericytoma of the na-sal cavity. Microscopically, the hem-angiopericytoma is a circumscribed,vascular neoplasm composed of aproliferation of spindle cells about nu-merous thin-walled endothelial-linedvascular spaces. These spaces mayvary from gaping, sinusoidal channelsto capillaries. (Hematoxylin & eosinstain; original magnification x40.)

cated additional left posterior ethmoid involvement. Abiopsy of the mass was suggestive of glomus tumor andthe patient was referred to our institution. The area wasagain imaged with both CT and MRI, which did not showsubstantial interval progression. The patient was taken tothe operating room August 1992 for endoscopic examina-tion and rebiopsy, which resulted in a subtotal excision ofthe mass. The biopsy revealed an HPC (Figs. 1, 2). Post-operative CT and MRI scans demonstrate residual tumorin the left sphenoid sinus (Figs. 3, 4). As the patient'sgeneral physical condition was poor, we elected to defersurgery and follow the lesion with serial physical exam-inations and CT and MRI scans. With more than 2 yearsof follow-up, there is no evidence of recurrent tumor.Furthermore, the residual tumor that had been present

186

following the subtotal excision is no longer detectable onphysical or radiographic examination (Fig. 5).

HISTOLOGIC APPEARANCE

Under light microscopy, HPC is characterized byvascular channels ranging from compressed fingerlikeprojections to capillaries and sinusoids. The vascular chan-nels may be unrecognizable before reticulin staining, whichhighlights the vascular nature of this lesion and demon-strates the tumor cells outside the vascular sheath. Aroundthese channels, pericytes proliferate in varying degrees ofdifferentiation. Because of the varying maturation ofthese cells, they can be difficult to distinguish from endo-

Figure 2. Higher power photo-micrograph of Figure 1. The hemangio-pericytoma is characterized by nu-merous capillary spaces surroundedby an accumulation of spindle cells.The tumor cells possess an oval orelongated nucleus with an indistinctcytoplasm. The organization of thesecells is very haphazard, but the cellu-lar confirmation is uniform. (Hema-toxylin & eosin stain; original magnifi-cation x200.)

SINONASAL HEMANGIOPERICYTOMA-THIRINGER ET AL

Figure 3. Axial computed to-mography scan demonstrating soft tis-sue mass in left posterior sphenoid si-nus (arrow). There is no evidence ofbony erosion.

Figure 4. Axial magnetic reso-nance scan, T1 weighted image withgadolinium contrast. Three monthsfollowing subtotal excision, an en-hancing left posterior sphenoid sinusmass is evident (arrow). 187

SKULL BASE SURGERYNOLUME 5, NUMBER 3 JULY 1995

Figure 5. Axial magnetic reso-nance scan, T1 weighted image withgadolinium contrast. Two years fol-lowing subtotal excision of hemangio-pericytoma, there is no evidence ofresidual or recurrent tumor.

thelial cells, fibroblasts, and histiocytes. Marked variationin histologic appearance allows HPC to be misdiagnosedas a glomus tumor, angiosarcoma, fibrous histiocytoma,lymphoma, hemangioendothelioma, and schwannoma.6,7Electron microscopy (EM) and immunohistochemicalstaining facilitate the histologic diagnosis of HPC asthe pericytes in these tumors usually retain features suffi-cient to make them recognizable.8'9 Immunohistochemi-cal staining demonstrates a strong staining pattern to vi-mentin, with approximately 20% of cases weakly positiveto actin, and 10% positive to S-100l1l2

With regard to histopathologic staging, HPC is gen-erally divided into three groups: low, intermediate andhigh grade. Staging features include tumor cellularity,mitotic figures, nuclear atypia, and the presence ofhemor-rhage and necrosis.5'13

* Low grade: These tumors have spindle-shapedpericytes with little crowding of vascular channels.There are few or no mitotic figures.

* Intermediate: These are more cellular tumors withplump pericytes and increased compression andcrowding of vascular spaces. Mitotic figures arestill not prominent.

* High grade: Characteristics include increase com-pression or obliteration of vascular spaces, increasedanaplasia, and increased mitotic figures.

This classification provides reasonable predictive valuewhen applied to all anatomic sites of tumor occurrence.This is particularly true with sinonasal disease in whichhistologic appearance and clinical coarse are consistently

188 benign.3,12

DISCUSSION

The biologic aggressiveness of HPC is well docu-mented in the literature, as is the more benign course ofthose lesions occurring in the nasal cavity and paranasalsinuses.7'914'15 Differences in behavior between HPC ofthe sinonasal tract and other somatic sites is significant,and has led some investigators to consider these as twoseparate tumor types.7 In a review of 23 cases of sinonasalHPC, Compagno and Hyams7 found a surprising anduncharacteristic histologic homogeneity among the group.Along with benign histologic features, they reported verylow rates of recurrence, metastasis, and mortality whencompared with lesions from other sites. This series wasconservatively reported as HPC-like tumors, possiblyrepresenting a distinct entity. Subsequent studies usingEM and immunohistochemical techniques have con-firmed that these tumors are, in fact, low-grade HPC andnot a distinct pathologic entity.9'12 In another review ofsinonasal HPC, Hughes and Bardl4 reported a series of 15cases over a 39-year period. They, too, note benign be-havior and confirm the true pericyte origin of these tu-mors through light microscopy and immunohistochemi-cal staining techniques. Interestingly, eight of these caseswere previously reported by Gorenstein and Facer16 in1978, thus adding 15 years of follow-up to the originalreport. From the Hughes and Bard data, three patientsdied from I to 12 years following the originally publishedseries; however, no deaths were due to HPC or its se-quelae. Combining the series, the longest follow-up todeath after surgery was 25 years in a patient who had been

SINONASAL HEMANGIOPERICYTOMA-THIRINGER ET AL

symptomatic for more than 37 years. Again, death wasnot related to HPC.

Recurrence rates for sinonasal HPC vary in the liter-ature from 7 to 50% (Table 1). Average time to recurrenceis 6 to 7 years with more than 30 years reported for a caseof ocular HPC.17 High recurrence rates have been tradi-tionally accepted in the literature and are usually corre-lated with incomplete tumor removal. When multipleseries are compared, it becomes clear that a substantialnumber of recurrent lesions are confined to a minority ofpatients. When the sinonasal tract is excluded, there areseveral reports of very aggressive HPC of the head andneck.18-20 Birzalgis et al2l reported on three cases of HPCinvolving the skull base, all with considerable local de-struction. One of the cases was treated with primaryradiation therapy (45 Gy) with some palliation of symp-toms for nearly 4 years. The tumor was removed via aninfratemporal fossa approach, with a small fragment ofknown disease remaining on the intrapetrous portion ofthe carotid artery. Over the next 2 years, the tumor re-lentlessly spread to intracranial and extracranial sites, butat death there were no known metastases. The other twocases in this report by Birzalgis et al are more recent anddo not have long-term follow-up.

Treatment recommendations for sinonasal HPC cen-ter around wide local excision, the specifics of which aredependent on tumor size and location. Lateral rhinotomyhas been the most frequently used surgical approach,although endoscopic techniques may be appropriate inselected cases.16,22 Specific tumor histologic findings areprobably not a significant factor in dictating therapy forsinonasal HPC. Isolated reports of chemotherapy andradiation therapy trials have met with limited success,although brachytherapy has shown early promise at localcontrol.6'23,24 Innovative surgical approaches have madean unresectable tumor the exception. When consideringan aggressive resection, it should be remembered thatvery few affected patients actually die from sinonasalHPC. Because of reported recurrences that are decadesremoved from primary treatment, lifelong follow-up ismandatory.

The reason for the low-grade behavior of sinonasal

Table 1. Recurrence Ratesof Sinonasal Hemangiopericytoma

Case TotalSeries No. * Recovered PercentCompagno and Hyams7 23 2 8Chowla25 23 11 47Backwinkel and Diddams26 21 12 57Gudrun6 15 5 13Hughes and Bard14 15 2 13El-Naggar and Batsakis15 14 2 14Gorenstein and Facer16 10 2 20Eichhorn and Dickersin12 9 4 44Hesham22 2 0 0*Number more than 100% of actual cases, as some cases reported inmultiple series.

HPC is unknown. At least part of the explanation may bethat nasal obstruction and epistaxis lead to earlier diag-nosis and treatment. In addition, there tends to be morepolypoid growth in sinonasal HPC instead of frank tissueinvasion, as occurs with other somatic tumor sites. Withseveral mature series of sinonasal HPC now reported, it isclear that with conservative treatment very few patientswill actually die of their disease. Based on this, we recom-mend conservative therapy for patients with sinonasalHPC. This conservative approach should consist of de-bulking the tumor so that sinonasal obstruction is relievedand careful follow-up with serial endoscopic examina-tions and imaging studies. We recommend aggressiveresection only if the tumor shows a propensity for growthand local invasion. In contrast to HPC occurring in so-matic sites, there appears to be little or no risk of meta-static spread of sinonasal HPC. Head and neck HPC inlocations outside of the sinonasal tract have demonstrateda more malignant character and merit a more aggressivetreatment plan.

REFERENCES

1. Stout AP, Murray MR: Hemangiopericytoma: A vascular tumorfeaturing Zimmermann's pericytes. Ann Surg 116:26-33, 1942

2. Stout AP: Hemangiopericytoma. A study of twenty-five newcases. Cancer 2:1027-1035, 1949

3. Batsakis JG, Rice DH: The pathology of head and neck tumors:Vasoformative tumors, part 9B. Head and Neck Surg 3:326-340, 1981

4. Blitzer A, Lawson W, Freidman WH: Surgery of the paranasalsinuses. Philadelphia: WB Saunders, 1985, pp 105-107

5. Enzinger FH, Smith BH: Hemangiopericytoma. An analysis of106 cases. Hum Pathol 7:61-82, 1976

6. Gudrun R: Hemangiopericytoma in otolaryngology. J LaryngolOtol 93:477-494, 1979

7. Compagno J, Hyams V: Hemangiopericytoma-like intranasal tu-mors. Am J Clin Pathol 66:672-683, 1975

8. Nunnery EW, Kahn LB: Hemangiopericytoma: A light micro-scopic and ultrastructural study. Cancer 47:906, 1981

9. Batsakis JG, Jocobs JB: Hemangiopericytoma if the nasal cavity:Electron optic study and clinical correlations. J Laryngol Otol97:361-368, 1983

10. Baker DL, Dolphine 0: Intraoral infantile hemangiopericytoma.Oral Surg Oral Med Oral Pathol 73:596, 1992

11. Osammor JY, Howat MR: View from beneath: Pathology in focusnasal hemangiopericytoma. J Laryngol Otol 105:593-595,1991

12. Eichhom JH, Dickersin GR: Sinonasal hemangiopericytoma: Areassessment with electron microscopy, immunohistochemistryand long term follow up. Am J Pathol 14:856-866, 1990

13. McMaster MJ, Soule EH: Hemangiopericytoma. A clinicopatho-logic study and long term follow-up of 60 patients. Cancer36:2232-2244, 1975

14. Hughes KV, Bard MC: Hemangiopericytoma of the nasal cavity; areview of 15 cases over a 40-year period. Am J Rhinol 6:203-209, 1992

15. El-Naggar AK, Batsakis JG: Sinonasal hemangiopericytoma: Aclinicopathologic and DNA content study. Arch Otol HeadNeck Surg 118:134-137, 1992

16. Gorenstein A, Facer GW: Hemangiopericytoma of the nasal cav-ity. Otolaryngology 86:405-415, 1978

17. Rice CD, Kersten RC: An orbital hemangiopericytoma recurrentafter 33 years. Arch Otolaryngol 107:552, 1989

18. Philippou 5, Gellrich C: Hemangiopericytoma of the head andneck region. Int J Oral Maxillofac Surg 21:99-103, 1992 189

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19. Volpe AG, Sullivan JG: Aggressive malignant hemangioperi-cytoma in the neck. J Surg Oncol 47:136-138, 1991

20. Gupta OP, Jain MS: Hemangiopericytoma in the head and neck.Ear Nose Throat J 64:145-149, 1985

21. Birzalgis AR, Ramsden RT, Lye RH, Richardson PL: View frombeneath: Pathology in focus. Hemangiopericytoma of the tem-poral bone. J Laryngol Otol 104:998-1004, 1990

22. Hesham M: Hemangiopericytoma of the maxillary sinus and skullbase. Head Neck 12:77-83, 1990

23. Ortega JA, Finkelstein JZ. Chemotherapy of malignant hemangio-

pericytoma of childhood: Report of a case and review of theliterature. Cancer 27:730-735, 1971

24. Wong PP, Yagoda A: Chemotherapy of malignant hemangioperi-cytoma. Cancer 41:1256-1260, 1978

25. Chawla P, Oswal VH: Hemangiopericytoma of the nose and para-nasal sinuses. J Laryngol Otol 101:729-737, 1987

26. Backwinkel K, Diddams JA: Hemangiopericytoma: Report of acase and comprehensive review of the literature. Cancer 25:896-901, 1970

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