Unusual non-epithelial tumours of the head and neck

Dr.Anandaselvakumar.

Extramedullary Plasmacytomas• Solitary plasmacytomas are rare tumors of plasma cell

origin making up 4% of all plasma cell tumors. Multiple myeloma occurs about 40 times more frequently than solitary plasmacytoma. Monoclonal extramedullary plasmacytoma (EMP) is a rare, low-grade lymphoma found predominantly in the head and neck region. Only since the introduction of immunophenotyping techniques two decades ago has it been possible to differentiate EMP from benign polyclonal plasma cell proliferation.. No EMP-related deaths occurred. Diagnostic procedures exclude a benign polyclonal plasmacytoma, multiple myeloma, and solitary bone plasmacytoma. The slow natural progression of the disease and the rarity of secondary multiple myeloma favor nonmutilating local surgery whenever possible to avoid the long-term sequelae of radiation.

Epidemiology• The annual incidence of EMP is 0.04 cases per 100,000 population.

They constitute only 0.5% of all upper respiratory tract malignancies. Male patients exceed female patients by a ratio of 4:1, and 75% of patients are 40 to 60 years of age.

• The most common sites in the head and neck are the nasopharynx, nasal cavity, paranasal sinuses, and tonsils.

Clinical Presentation and Diagnostic Work-Up• EMP of the head and neck area should be considered a separate

entity because of its clinical behavior. The most common symptoms are nasal obstruction, local pain and swelling, and epistaxis.

• Grossly, plasmacytomas tend to be sessile in the nasal cavity and paranasal sinuses and pedunculated in the nasopharynx and larynx. The masses are soft, pliable, and pale gray. The lesion may remain localized or may infiltrate and destroy the surrounding soft tissue and bone.

• The usual criteria for solitary plasmacytomas, either medullary or extramedullary, include a biopsy-proven plasma cell tumor with one or, at the most, two solitary foci, absence of Bence-Jones protein in the urine, bone marrow taken some distance from the primary site not involved by tumor (<10% of plasma cells), hemoglobin of 13 g/mL or more, and a normal serum protein level or serum electrophoresis at the time of the diagnosis.

• Basically, the diagnosis of solitary plasmacytoma is made by exclusion, that is, by eliminating the possibility of multiple myeloma. Diagnosis is based on histology along with special immunoperoxidase staining for immunoglobulin lambda and kappa light chains

• Bone destruction is not a particularly bad prognostic sign, although some investigators report that it adversely affects prognosis. Bony invasion is common in the more malignant types

• The exact relationship between EMP and multiple myeloma is unclear; however, approximately 20% to 30% of EMP cases will convert to multiple myeloma

Radiation Therapy Techniques• Irradiation techniques vary with the location of the

primary tumor. The techniques are similar to those used for primary tumors in comparable locations (i.e., nasopharynx, tonsil, paranasal sinuses). Solitary plasmacytomas respond well to doses of 50 to 60 Gy in 2-Gy fractions. The local tumor control rate with radiation therapy alone is about 85%.

• Harwood et al. summarized the literature but could not draw a dose–response curve from the data because of a lack of cases receiving low-dose radiation therapy. Nevertheless, there is a high risk of local recurrence with tumor doses below 30 Gy and a negligible risk for those treated at or above 40 Gy.

• Our limited experience confirms the efficacy of tumor doses of 45 to 50 Gy for local tumor control. In patients who had extensive disease, a higher dose (50 to 60 Gy) was used, as recommended by several investigators

Nasopharyngeal AngiofibromaEpidemiology• Juvenile nasopharyngeal angiofibroma (JNPA) is found more

frequently in young pubertal boys; it has been shown to contain androgen receptors and occasionally to regress with estrogen therapy. androgen receptors in 75% cases, whereas only 8.3% were positive to progesterone.

• JNPA comprises <0.05% of head and neck tumors . Patient age at presentation ranges from 9 to 30 years, with a median of 15 years. Females comprise <4% of the total cases. Some investigators have suggested chromosomal studies in affected women because this is mainly a male disease.

• The tumor is believed to originate from the posterolateral wall of the nasal cavity where the sphenoidal process of the palatine bone meets the horizontal ala of the vomer and the roof of the pterygoid process because it is always involved. Other investigators agree, because involution of tumor after irradiation usually occurs in this direction.

Clinical Presentation and Pathology• Symptoms usually occur 2 to 48 months before diagnosis. The most

common complaints are nasal obstruction or epistaxis, followed by nasal voice or discharge, cheek swelling, proptosis, diplopia, hearing loss, and headaches.

• Nasopharyngeal angiofibroma may initially extend into the nasal fossae and maxillary antrum and push the soft palate downward, then through the pterygopalatine fossa and superoanteriorly through the inferior orbital fissure or laterally through the pterygomaxillary fissure to the cheek and temporal regions

Diagnostic Work-Up• After the history and physical examination, CT scans

with and without contrast should be obtained. The pattern of enhancement in this highly vascular tumor is diagnostic (164,192), and many investigators believe carotid angiograms are unnecessary (30) after CT diagnosis of the lesion, unless embolization, which is also controversial, is contemplated.

• CT scans are especially helpful in regions involving thin bony structures (paranasal sinuses, orbits), where CT performs better than MRI. In the nasopharynx and parapharyngeal space MRI is superior to CT. Obtaining tumor volumetric data with spiral CT or MRI facilitates 3D treatment planning.

• If intracranial extension is noted and radiation therapy is contemplated, no further studies are indicated. If the lesion is extracranial and surgery is indicated, bilateral carotid angiograms will identify the feeding vessels and delineate the boundaries of the tumor

• Biopsies are not indicated in all patients because of the potential for severe hemorrhage. It is important to perform a biopsy of the lesion when the clinical picture (sex, age, location, and behavior of the lesion) is not consistent with JNPA because some lesions have proven to be sarcomas or chronic sinusitis

Staging and Prognostic Factors

• Two staging schemes have been proposed: (a) the system of Chandler et al. and (b) a radiographic staging system by Sessions et al. . • Stage Ia is limited to the nasopharynx and posterior nares; • stage Ib extends to the paranasal sinuses; • stages IIa, IIb, and IIc extend to other extracranial locations; and • stage III is intracranial.• In a retrospective review of 44 cases of juvenile nasopharyngeal

angiofibroma, invasion of the skull affected two thirds of the patients, and the rate of recurrence was 27.5%.

• Extensions to the intratemporal fossa, sphenoid sinus, base of pterygoids and clivus, the cavernous sinus (medial), foramen lacerum, and anterior fossa were correlated with more frequent recurrence.

• Long-term radiographic follow-up showed residual disease in nine asymptomatic patients: these remnants gradually involuted.

General Management• The decision of whether surgery or radiation therapy, depends in part on the

initial extent of the disease. In patients with extracranial tumors, surgery is the treatment of choice and yields near-zero mortality or any long-term morbidity.

• Tumor remnants in symptomfree patients should be kept under surveillance by repeated CT scanning, since involution may occur. Recurrent symptoms may be treated by radiation therapy rather than by extended surgery or combined procedures.

• When there is intracranial tumor extension, the risk of surgically related death increases. Most of these patients are best treated with irradiation.

• Preoperative intraarterial tumor vessel embolization at the time of diagnostic bilateral carotid angiography can be used, claiming a decrease in operative bleeding.

• Salvage with embolization of polyvinyl alcohol has been described. • Others have reported anecdotal evidence of partial regression with the use

of estrogens, believed to be the result of feedback inhibition of the pituitary's production of gonadotropin-releasing hormone

• Although radiation therapy is equally effective in extracranial tumors, the low but existing risk of secondary malignancies should limit its use to the most advanced tumors only.

• In the experience of Cummings et al. covering 20 years, only two radiation-related malignancies were noted (one skin, one thyroid).

Radiation Therapy Techniques• Photon irradiation should be used for these patients, and fields must be

individualized to cover the tumor completely with a margin (1 to 2 cm). • Treatment portals are similar to those used in carcinoma of the nasopharynx

(without irradiating the cervical lymph nodes) or carcinoma of the paranasal sinuses when these structures or the nasal cavity is involved. Opposing lateral portals are suitable in most patients, with larger fields and compensators used for tumors extending into the nose.

• More extensive disease requires three-field or wedge-pair arrangements of 3DCRT or IMRT that can yield excellent dose distributions, particularly when there is nasopharyngeal or intracranial tumor extension.

• In all cases the eyes are protected as much as possible. • The recommended tumor dose ranges from 30 Gy in 15 fractions in 3 weeks

to 50 Gy in 24 to 28 fractions in 5 weeks. A conventional setup uses 6- to 18-MV photons to treat the lesion with parallel-opposed fields to 50 Gy (2-Gy fractions)

• The advantages of IMRT for the treatment of extensive and/or recurrent JNPA has been described in three patients on whom the tumor affected the base of skull, pterygopalatine, and intratemporal fossae, posterior orbit, and nasopharynx Tumor dose varied from 34 to 45 Gy.

• The tumor shrunk radiographically in all three cases, and there was no endoscopic evidence of disease in two cases at 15 months and 40 months. Late toxicity was limited to one episode of epistaxis and persistent rhinitis in one patient.

• Diagrams of the most commonly used conventional field arrangements for treatment of nasopharynx angiofibroma: lateral opposed field pair and three-field technique.

Diagrams of the most commonly used conventional field arrangements for treatment of nasopharynx angiofibroma: lateral opposed field pair and three-field technique.

Results of Therapy • Jones et al. reported the results of 40 patients with JNPA treated with

surgery alone. With a mean follow-up of 17 months (6 to 36 months), the control rates according to the Sessions staging system were as follows: 100% (stages I and IIa), 83% (stage IIb), 80% (stage IIc), and 50% (stage III). All failures were controlled with irradiation, embolization, or surgical resection, and the others were observed only, demonstrating the extremely high salvage rate in this disease. These findings are consistent with other series reporting initial surgical control of 86% with an ultimate control rate of 96%.

• Goepfert et al. (100) reported on five patients with aggressive nasopharyngeal angiofibromas recurrent after extracranial resection and irradiation who were treated with chemotherapy. Doxorubicin (60 mg/m2 intravenous [IV] push for 1 day) and dacarbazine (250 mg/m2 IV drip for 5 days) were given, with courses being repeated every 3 to 4 weeks. In a second regimen, vincristine, dactinomycin, and cyclophosphamide were administered at usual doses. Excellent tumor regression was noted in all patients. Patients were disease free at 2, 3, 6, and 10 years.

• At the Mallinckrodt Institute of Radiology, Fields reviewed our experience with 13 patients: 11 surgical failures and two primarily treated with irradiation. Intracranial extension was noted in 38% of patients. Follow-up ranged from 40 to 173 months. Doses ranged from 36 to 52 Gy, with a median of 48 Gy (1.8 to 2 Gy per fraction, 5 days a week). The control rate was 85%; patients failing irradiation were salvaged with embolization. Late morbidity was mostly xerostomia and dental decay.

Extracranial Meningiomas• Extracranial meningiomas of the sinonasal tract are rare tumors. The overall

prognosis is good, without a difference in outcome between benign and atypical meningiomas.

• Mean 47.5 years. • Patients presented clinically with a mass, epistaxis, sinusitis, pain, visual

changes, or nasal obstruction, dependent on the anatomic site of involvement.

• Tumors size ranged from 1 to 8 cm (mean, 3.5 cm). • Radiographic studies demonstrated a central nervous system connection in

six cases; the tumors often eroded the bones of the sinuses and involved the surrounding soft tissues, the orbit, and occasionally the base of the skull.

• Histologically, the tumors demonstrated features similar to intracranial meningiomas; the majority of the meningothelial type, although there were three atypical meningiomas.

• Immunohistochemical studies confirmed the diagnosis with reactions for epithelial membrane antigen and vimentin. The differential diagnosis included paraganglioma, carcinoma, melanoma, psammomatoid ossifying fibroma, and angiofibroma.

• Surgical excision was used in all patients. Three patients died with recurrent disease (mean, 1.2 years), one was alive with recurrent disease (25.6 years), and the remaining 24 patients were alive or had died of unrelated causes (mean, 13.9 years) at the time of last follow-up (two patients were lost to follow-up).

Nonlentiginous Melanoma• Malignant melanoma accounts for 11% of primary head and neck

malignancies. Of all malignant melanomas, 20% to 35% are located in the head and neck area.

Cutaneous Melanomas• Of all head and neck malignant melanomas, 64% to 78% were cutaneous,

6% to 8% were mucosal, and 14% to 30% were ocular. • The superficial spreading and nodular types of malignant melanoma have

a metastatic potential of 10% to 30% and 50%, respectively. • Neurotropic melanoma is an uncommon variant of cutaneous melanoma,

with a higher propensity to invade peripheral nerves. A thorough evaluation with CT scans should determine if there is intracranial or base of the skull involvement.

• Treatment of cutaneous melanomas has typically been wide excision of the lesion with a minimum 3-cm margin. More recently, margins of at least 2 cm have been used in the head and neck area compared with wider margins for stage I melanomas, with equivalent success as noted by the local failure rate of 3% to 6%.

• Another approach to the treatment of recurrent or unresectable cutaneous melanomas is combined hyperthermia and high-fraction radiation therapy

• a randomized study by the Radiation Therapy Oncology Group comparing four fractions of 8 Gy given on days 0, 7, 14, and 21 and 20 fractions of 2.5 Gy in 5 weekly fractions showed no significant difference in tumor response

Mucosal Melanomas• Primary mucosal melanomas of the head and neck area

comprise 2% to 8% of the cases seen each year in the United States. They occur more commonly in countries such as Japan, where mucosal melanoma is found in 22% to 32% of patients with malignant melanoma. Most occur in the fifth to seventh decades of life; they are extremely rare in the first two decades.The male-to-female ratio approaches 1:1.

• 56.4% to be from the upper respiratory tract and 44% from the oral cavity and pharynx. Nasal cavity/paranasal tumors comprise <1% of malignant melanomas and 2% to 9% of head and neck melanomas.

• Pigmentation may precede the lesion in up to 28% of patients for more than 1 year. In the oral cavity, the most common location is the hard palate (up to 80%), followed in order of decreasing frequency by the upper gingiva and lower gingiva.

Diagnostic Work-Up• An excisional biopsy should be performed when feasible

because some reports have suggested possible local or metastatic spread secondary to a punch or incisional biopsy, although this has not been noted in cutaneous melanomas. one third of these lesions were amelanotic.

• Metastatic melanoma to the mucosa of the head and neck area is less common. It can be differentiated from primary tumors by the presence of normal tissue between subepidermal tumor and the basal layer of melanocytes. In a review of the literature. The larynx, tongue, and tonsils are the most common locations for metastases.

Prognostic Factors• >0.5 mm invasion, be a poor prognostic factor. Lymph

node involvement is not a prognostic factor. Mucosal melanomas fare worse than their cutaneous counterparts, suggesting a lack of immunologic competence.

Management and Results of Therapy• In a review of the Japanese literature, Umeda et al. found a local

tumor control rate for stage I and II disease of 58% (7/12) in surgically treated patients with oral melanomas and a minimum follow-up of 3 years. Similar rates of failure have been reported, even with radical en bloc excisions (20% to 42%).

• Because the main cause of treatment failure is distant metastases and because almost no patient has clinically evident nodal metastases at presentation, an elective neck node dissection is not recommended by some investigators. This subject is still controversial because 30% to 60% of patients may later develop nodal disease.

• Postoperative radiation therapy was with 60Co or 4-MV photons, 50 to 60 Gy, 1.5 to 2 Gy per fraction, over a period of 5 to 6 weeks.

• Patients with nasal cavity/paranasal mucosal melanoma have a median survival of 24 months.

• Because the results with irradiation are comparable with those of surgical series and because of the poor survival of these patients due to distant metastases and not locoregional failure, irradiation alone, with surgery for salvage, should be seriously considered as the primary treatment for mucosal melanomas of the head and neck

Lentigo Maligna MelanomaNatural History• Lentigo maligna (Hutchinson's melanotic freckle or

circumscribed precancerous melanosis of Dubreuilh) and its invasive counterpart, lentigo maligna melanoma (LMM), are well-recognized clinicopathologic entities. LMM comprises about 10% of all melanomas in the head and neck, occurs predominantly on the face and ears of elderly persons, and generally has a very long natural history, frequently reaching a large size before diagnosis. Approximately one third of lentigo maligna lesions, if left untreated, will eventually transform into invasive LMM.

• Tannous et al. hypothesized that lentigo maligna can be divided into two categories: one represents a pigmented lesion that is a precursor to melanoma, and the other melanoma in situ. Also, they hypothesized that in some patients there is a progression to malignant melanoma.

Clinical Presentation and Diagnostic Work-Up• These lesions appear as circumscribed and later as

more diffuse areas of hyperpigmentation of the skin. They may develop some superficial nodularity and eventual ulceration as they become more invasive. In 10% of the latter patients, regional and distant metastases eventually develop. The 10% metastatic spread in LMM contrasts with the 25% metastatic tendency in nodular melanomas arising in superficial spreading melanomas and a 50% metastatic spread in nodular melanomas arising de novo.

• The diagnostic work-up of these patients is similar to that of patients suspected of having malignant melanoma. Biopsies of the lesion are required to obtain histopathologic confirmation of the diagnosis. Careful physical examination must rule out any areas of extension or regional or distant spread.

General Management• The usual treatment of lentigo maligna and LMM

has been surgery, with approximately 1- to 2-cm margin of normal skin.

• Hill and Gramp reported on 66 cases of lentigo malignant melanoma; 38% of which required two excisions or more to clear the tumor and 32% of cases showed evidence of invasive melanoma. Only one case has recurred thus far, and none have developed metastatic disease.

• Because of the low incidence of regional lymph node metastases, elective lymph node dissection is not indicated. For larger lesions, wider surgical excision with skin grafting has been reported to give poor cosmetic results.

Radiation Therapy Techniques

• Entire tumor with adequate margin (1 cm for lesions <2 cm and 2 cm for larger tumors).

• Because Miescher's irradiation technique used very superficial x-rays, with 50% depth dose being at approximately 1 mm, there is the possibility of local recurrence if dermal extension is unrecognized. minimum x-ray energies of 100 keVp is used and preferably 140 to 175 keVp to treat these patients.

• Superficial x-rays (100 to 200 keVp) with adequate filtration or electrons (6 to 9 MeV) with appropriate thickness of bolus (about 1.5 cm) are adequate for most patients.

• Doses of 45 to 50 Gy in 15 to 25 fractions delivered over 3 to 5 weeks will control the disease in most patients.

• It is recommended delivering 3 to 3.5 Gy, three times weekly, every other day, to a total of 50 Gy, depending on the size and thickness of the lesion.

• Elective irradiation of the regional lymphatics is not necessary.• In patients on whom surgical excision is performed, postoperative

irradiation is recommended if positive margins are found. Doses are similar to those stated earlier.

Sarcomas of the Head and NeckNatural History• Sarcomas account for <1% of malignant neoplasms in the head and

neck. The most frequent histological type is malignant fibrohistocytoma, while the least common is liposarcoma (1%).

• The histology is complex and requires immunochemical analysis including osteosarcoma, angiosarcoma, chondrosarcoma, hemangiosarcoma, leiomyosarcoma, liposarcoma, malignant fibrous sarcoma, rhabdomyosarcoma, malignant schwannoma, neurofibrosarcoma, and synovial sarcoma. Fibrosarcoma, angiosarcoma, leiomyosarcoma, and rhabdomyosarcoma are the most common types but this varies in published reports.

• Distribution of these sarcomas was 33% in the scalp or face, 26% in the orbit or paranasal sinuses, 14% arising from upper aerodigestive tract including larynx, and 27% in the neck.

• Synovial sarcomas are rare soft-tissue malignancies in the head and neck region; they account for 3% to 5% of head and neck tumors.

• Histologic, immunohistochemical, and characteristic chromosomal translocation findings are necessary for diagnosis.

• The poor prognosis of this sarcoma justifies radical surgery with postoperative radiation.

• Radiation-induced sarcoma of the head and neck is a rare long-term complication of treatment.

• When they do occur, most appear at least 10 years following radiation therapy.

• There is a possibility of a postirradiation sarcoma whenever a suspicious lesion is seen, regardless of the amount of time that has passed since radiation therapy was administered.

Clinical Presentation and Diagnostic Work-Up• Clinical presentation varies with the primary site of

disease.• nasal bleeding, a palpable mass in the neck, or difficulty

in swallowing or breathing, cranial nerve deficit. Diagnostic work-up follows that of soft-tissue sarcomas of other sites in the body. With early lesions, radiographs or CT may show only nonspecific opacification, soft-tissue swelling, and occasionally bone destruction. MRI, especially with gadolinium contrast, may be used as a supplement or alternative to CT scanning. A CT scan of the chest is also mandatory for staging work-up.

• The American Joint Committee on Cancer (AJCC) staging system for soft-tissue sarcomas is based on histologic grade, the tumor size and depth, and the presence of distant or nodal metastases. The staging system is the same as for sarcomas of the extremities, although specific staging for head and neck sarcomas is not standardized

Prognostic Factors• Prognostic factors for predicting local recurrence or

disease-free survival include anatomic site, treatment modality, tumor histology and grade, tumor size, extension of disease, and surgical margins

• In addition to tumor grade and size, direct tumor extension to neurovascular structures, bone, contiguous organs, and skin was associated with a higher incidence of distant metastasis. The actuarial 5-year freedom-from-distant-metastasis rates were 70% and 100% for tumors with or without direct extension, respectively

• Stage IA T1a NO NX M0 G1-2 G1 LowT1b N0 NX M0 G1-2 G1

Low

• Stage IB T2a N0 NX M0 G1-2 G1 LowT2b N0 NX M0 G1-2 G1

Low

• Stage IIA T1a N0 NX M0 G3-4 G2-3 HighT1b N0 NX M0 G3-4 G2-3 High

• Stage IIB T2a N0 NX M0 G3-4 G2-3 High

• Stage III T2b N0 NX M0 G3-4 G2-3 High

• Stage IV Any T N1 M0 Any G Any G High or Low

Any TAny N M1 Any G Any G High or

Low

STAGE GROUPING

General Management• Surgery is the preferred initial treatment modality for sarcomas. • Unfortunately, it is often difficult to achieve complete resection of the tumor,

and a high recurrence rate has been observed with surgery alone. Extracapsular enucleation of the tumor results in 90% local recurrence because of the presence of microscopic pseudopodia, which tend to grow through the pseudocapsule into the surrounding tissue and the presence of skipped lesions some distance from the main tumor mass. Pathologic analysis of the surgical bed often discloses microscopic extension of tumor.

• This resulted in inferior overall survival for sarcomas of the head and neck when compared with extremity sarcomas. Wide local excision, with a 5-cm margin around the pseudocapsule in extremity sarcomas, is associated with better outcome, although approximately 20% will have local recurrence.

• The criteria for surgical resection are impractical for head and neck sarcomas because of anatomic limitations. Some retrospective studies have suggested improved local tumor control when combined surgery and external irradiation are used. Patients treated with combined-modality treatment (surgery and irradiation) had less extensive surgery, yet local recurrencefree survival was longer.

• Radiation therapy, by external beam or brachytherapy, plays an important adjunctive role in the management, especially for tumors where en-bloc resection with negative margin is not possible.

• Chemotherapy regimens are available for soft-tissue neoplasms primarily designed to improve local tumor control. Survival is predicted on the incidence of local recurrence and risk of distant metastasis, both of which are influenced by tumor grade.

• There was evidence that adjuvant radiotherapy improves local tumor control in combination with conservative surgery with negative, marginal, or minimal microscopic positive surgical margins.

• There are still insufficient data to establish that preoperative radiotherapy is favorable compared to postoperative radiotherapy in patients presenting primarily with large tumors. The preoperative setting results in more wound complications.

• There is no randomized study comparing external beam radiotherapy and brachytherapy. The data suggest that external beam radiotherapy and low–dose-rate brachytherapy result in comparable local control for high-grade tumors. Some patients with low-grade soft-tissue sarcomas benefit from external beam radiotherapy in terms of local control. Brachytherapy with a low dose rate for low-grade tumors seems to be of no benefit, but data are sparse. In two small studies investigating hyperfractionation schedules there was no indication of improvements compared to daily fractions of 2 Gy.

• Mesenchymal chondrosarcoma of the sinonasal tract is a rare, malignant tumor of extraskeletal origin.Present as nasal obstruction, epistaxis, or mass effect, or a combination of these. The maxillary sinus was the most common site of involvement, followed by the ethmoid sinuses and the nasal cavity.

• All cases were managed by surgery with adjuvant radiation therapy and/or chemotherapy.The overall mean survival was 12.1 years.

• A multidisciplinary discussion before the initiation of treatment is required to formulate the best approach for radiation delivery, surgical technique, and mode of reconstruction.

Radiation Therapy Techniques• The general principles for radiation therapy of head and

neck sarcomas are similar to those of soft-tissue sarcomas.

• Complete coverage of the surgical bed and scar with adequate margins (3 to 5 cm) is required. However, because of the proximity of critical and radiosensitive organs (eyes, spinal cord, brainstem), selecting optimal portal margins without seriously compromising the functioning of these organs is an art.

• Techniques similar to those used in epithelial tumors of the head and neck can be applied to sarcomas.

• In general, 55 to 60 Gy is needed for postoperative adjuvant irradiation, and an additional 10- to 15-Gy boost is recommended if the surgical margins are close (<3 mm) or involved by tumor.

• Some institutions prefer preoperative irradiation of 45 to 50 Gy. Special attention should be directed to limiting the dose to critical structures.

Chemotherapy• Head and neck soft-tissue sarcomas frequently

metastasize. • The role of adjuvant chemotherapy to improve

diseasefree survival in sarcoma of the head and neck is controversial.

• Unlike with soft-tissue sarcomas of the extremities, in which distant metastasis is the most common cause of death, the majority of deaths in sarcomas of the head and neck are associated with local failure. Approximately half of the distant metastases were detected after local recurrence occurred. Chemotherapy did not appear to affect local tumor control

• For preoperative neoadjuvant chemotherapy, which supplements radiation therapy to downstage disease before surgery, satisfactory results are available only for sarcomas of extremities.

• With the exception of rhabdomyosarcoma, postoperative adjuvant chemotherapy should be given only in a clinical trial setting.