Introduction
Rhabdomyosarcomas represent 40 per cent of all head and neck sarcomas.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1 Although they are the most common soft tissue sarcomas of childhood (with an annual incidence of 4–7 per million children), they rarely appear in adults (being the third most common sarcoma in this age group).Reference Dagher and Helman2–Reference Masson and Soule4 The majority of head and neck rhabdomyosarcomas occur in the orbit, nasopharynx, nasal cavity and paranasal sinuses.Reference Masson and Soule4 Laryngeal involvement occurs in only 3 per cent of head and neck rhabdomyosarcomas.Reference Barnes, Ferlito and Ferlito5
We present a case of subglottic laryngeal rhabdomyosarcoma in an elderly woman, which was treated by endoscopic resection.
The histological classification of rhabdomyosarcomas is controversial. Most authors accept the system proposed by Horn and Enterline.Reference Newton, Gehan, Webber, Marsden, van Unnik and Hamoudi6 According to this system, there are three major histological rhabdomyosarcoma subtypes: embryonal, alveolar and pleomorphic.
Case report
An 83-year-old woman presented to our department with a three-month history of progressive dyspnoea. She reported that a subglottic lesion had been removed under general anaesthesia seven years previously, and had been reported as a haemangioma.
On physical examination, the patient had tachypnoea, stridor and intercostal recession.
Fibre-optic laryngoscopy showed a large, exophytic mass arising from the subglottis.
The patient underwent an emergency tracheostomy under local anaesthesia; however, due to a severe arrhythmia during surgery, biopsies were not performed at the time.
Subsequent high resolution computed tomography (CT) scanning showed a large, subglottic mass with 95 per cent obstruction of the lumen. Chest radiography and CT scans of the thorax and abdomen were normal.
Direct microlaryngoscopy was performed three months later, as the patient suffered a stroke three weeks following her tracheostomy. It was possible to fully excise the lesion macroscopically, endoscopically as well as through the tracheostomy.
The patient recovered well and there were no post-operative complications.
Histopathological examination revealed a laryngeal pleomorphic rhabdomyosarcoma. Grossly, the tumour mass was whitish and firm with areas of haemorrhage, and measured 4 × 2.5 × 1 cm. Microscopically, the tumour was diffuse and cellular without any distinct morphological pattern. Ulceration was found on the surface epithelium. In the biopsy specimen, there was a variation in the cellularity, with alternating hyper- and hypocellular areas; the latter were associated with a myxoid stroma. The cellular components consisted of round cells (resembling lymphocytes) with dark nuclei, and also larger oval- to spindle-shaped cells with eccentric, eosinophilic cytoplasm. Mitotic figures and necrosis were easily assessed. Immunoperoxidase stains were positive for desmin, vimentin and myoglobulin and negative for S100 protein, cytokeratin (CAM 5.2), smooth muscle antigen, Leucocyte common antigen, carcinoembryonic antigen and cluster of differentiation 68 glycoprotein (Figure 1).
Photomicrographs: (a) H&E, ×4; (b) Masson trichrome staining, ×10; (c) desmin immunoreactivity staining, ×20; (d) vimentin immunohistochemical staining, ×20.
Due to the patient's age and physical condition, no further treatment was pursued. The patient was followed up regularly every three months, and eventually died 16 months after her operation from a second stroke, free of disease.
Discussion
Rhabdomyosarcoma is the most common soft tissue neoplasm of the head and neck in children, and usually appears during the first decade of life.Reference Dagher and Helman2 It is more rarely found in adults (being the third most common soft tissue sarcoma in this age group). Although the most common site of presentation is the head and neck region (approximately 35 per cent), laryngeal rhabdomyosarcoma is extremely rare, and institutional experience is thus quite limited, with only a few published reports.Reference Masson and Soule4 Males tend to be affected more than females.Reference Dikbas, Altundag, Abali, Turker, Engin and Sungur7 Only two female cases have been reported in the literature, including the present case (see Table 1).
Reported adult cases of laryngeal rhabdomyosarcoma
No = number; pt = patient; yrs = years; mths = months; wks = weeks; M = male; F = female; R = right; L = left; post = posterior; ant = anterior; RT = radiotherapy; CT = chemotherapy; bilat = bilateral; NS = not specified; pre-op = pre-operatively; approx = approximately
The most widely accepted classification for rhabdomyosarcomas is that of Horn and Enterline.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1, Reference Newton, Gehan, Webber, Marsden, van Unnik and Hamoudi6 This system classifies rhabdomyosarcomas into three basic histological types: embryonal, alveolar and pleomorphic. Botryoid rhabdomyosarcoma is considered to be a subtype of embryonal rhabdomyosarcoma.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1, Reference Knipe, Chandra and Bugg26 Newer, rare histological types such as spindle cell and sclerosing rhabdomyosarcoma have been reported in both children and adults.Reference Knipe, Chandra and Bugg26 Embryonal rhabdomyosarcoma tends to appear mainly in infants and young children, while the alveolar type is more common in young adults.Reference Ferrari, Dileo, Casanova, Bertulli, Meazza and Gandola27–Reference Esnaola, Rubin, Baldini, Vasudevan, Demetri and Fletcher30 Pleomorphic rhabdomyosarcoma is usually found in older adults, although an overlap often occurs.Reference Aleksandar, Filipce, Caparevski and Stavrić13, Reference Bizer31
The differential diagnosis of rhabdomyosarcoma includes lymphoma, fibrosarcoma, melanoma, neuroblastoma, retinoblastoma, haemangioendothelioma and granular cell myoblastoma.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1, Reference Akyol, Sozeri, Kucukali and Ogretmenoglu24, Reference Knipe, Chandra and Bugg26 Special stains and immunohistochemical markers are necessary to establish a histological diagnosis.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1, Reference Ruske, Glassford, Costello and Stewart23
The symptomatology of laryngeal rhabdomyosarcomas is usually quite similar to that of other laryngeal tumours.Reference Dikbas, Altundag, Abali, Turker, Engin and Sungur7, Reference Ruske, Glassford, Costello and Stewart23 The anatomical position of such tumours, along with their rapid growth, usually result in a more advanced clinical appearance than the more commonly observed laryngeal squamous cell carcinoma.Reference Ruske, Glassford, Costello and Stewart23 The most common signs and symptoms of laryngeal rhabdomyosarcoma include hoarseness of voice, dyspnoea, stridor and dysphagia, while pain and weight loss are relatively rare, usually indicating advanced disease.Reference Dikbas, Altundag, Abali, Turker, Engin and Sungur7, Reference Ruske, Glassford, Costello and Stewart23, Reference Akyol, Sozeri, Kucukali and Ogretmenoglu24
Computed tomography and MRI usually provide valuable information about tumour size and location, nerve or vascular invasion, and bony erosion.Reference Dikbas, Altundag, Abali, Turker, Engin and Sungur7, Reference Akyol, Sozeri, Kucukali and Ogretmenoglu24, Reference Knipe, Chandra and Bugg26 Computed tomography is often preferred when information about laryngeal cartilage erosion is needed.
Surgical excision appears to be the treatment of choice for laryngeal rhabdomyosarcoma.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1 Of the reported cases in adults, only two patients were not treated surgically. Emergency tracheostomy was performed in some cases because the airway was at grave risk by the time of admission. Most of the remaining cases underwent total laryngectomy. However, according to Da Mosto et al., conservative laryngectomy should be employed if the tumour can be adequately removed.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1 Conservative procedures such as partial laryngectomy, cordectomy or tumour debulking are supported by some authors when the tumour is resectable, mainly because these laryngeal lesions tend to be less aggressive than other head and neck rhabdomyosarcomas, and it is believed that the laryngeal cartilages may act as anatomical barriers to tumour expansion.Reference Frugoni and Ferlito12, Reference Ruske, Glassford, Costello and Stewart23, Reference Akyol, Sozeri, Kucukali and Ogretmenoglu24, Reference Canalis, Platz and Cohn32
In our patient, emergency tracheostomy was performed in order to secure the patient's airway, and the tumour was macroscopically removed at a second stage. No other therapeutic procedure was involved, and the patient survived for 16 months following her operation, subsequently dying from an unrelated cause with no evidence of recurrence. Her survival time is comparable to that of other patients treated with nonconservative methods. Although some authors suggest that a radical excision is preferable in such lesions, a large number of surgical cases would be needed in order to determine whether prognosis is related to the extent of tumour removal. Neck dissection is not usually suggested, as rhabdomyosarcomas do not generally metastasise to cervical lymph nodes.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1, Reference Masson and Soule4 Cervical lymph node infiltration has been reported in only one case (case 14, Table I). Distant metastasis of laryngeal rhabdomyosarcoma has not been reported.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1
The role of radiotherapy in the management of laryngeal rhabdomyosarcoma remains controversial. Radiotherapy has been used as primary and adjuvant therapy in several cases.Reference Ruske, Glassford, Costello and Stewart23 The results were variable and difficult to interpret, as radiotherapy often followed radical excision of the tumour. Radiotherapy was adopted as the only therapeutic procedure in two reported cases. Grouls and Bechtelsheimer reported that their patient died of cardiogenic shock three weeks later, while Franz's patient was alive and disease-free after two years.Reference Grouls and Bechtelsheimer10, Reference Franz17
Chemotherapy has been involved in four cases of laryngeal rhabdomyosarcoma (see Table I). A number of chemotherapeutic agents appear to be effective against rhabdomyosarcoma, including vincristine, cyclophosphamide and actinomycin D.Reference Dagher and Helman2 It has been suggested that rhabdomyosarcoma is the only tissue sarcoma for which chemotherapy may have a significant adjunctive role when used alongside both surgery and radiotherapy.Reference Haerr, Turalba, el-Mahdi and Brown20, Reference Edmondson33 Triple therapy seems to have encouraging results in embryonal and botryoid laryngeal rhabdomyosarcomas.Reference Da Mosto, Marchiori, Rinaldo and Ferlito1 The efficacy of chemotherapy can be augmented by concurrent use of several agents (i.e. combination chemotherapy).Reference Dagher and Helman2
Conclusion
Rhabdomyosarcomas are soft tissue neoplasms which rarely involve the adult larynx. It is not uncommon for airway obstruction to occur quite early in such patients, requiring immediate airway intervention. Despite the fact that these tumours are traditionally treated aggressively, this approach is not supported by the literature, which remains scarce. Due to the variable biological behaviour of this tumour in adults, we believe that conservative surgical procedures or combination therapy should be considered, rather than total laryngectomy, depending on the tumour size and location and the patient's age and physical condition.
