Rhabdomyosarcoma of the parotid region in a child by Larhrabli Ibtissam in Journal of Clinical Case Reports, Medical Images and Health Sciences

Rhabdomyosarcoma of the parotid region in a child by Larhrabli Ibtissam in Journal of Clinical Case Reports, Medical Images and Health Sciences

Abstract :

Background: A rare case of Rhabdomyosarcoma of parotid in child ,localy advanced , well treated , better outcome. Case presentation: An 8 year old child , from a rural region near casablnca , with no medical history has developped a mass in the left parotid region growing fast, fixing a facial paralysis within 3 months , diagnosed with ct scan and biopsy , the patient underwent surgery for mass reduction and chemotherapy ivado than iva protocol , a notable reduction of the swelling was noticed after one year.

 Conclusion: 

Rhabdmyosarcoma is a rare type of sarcoma that affect children, the early diagnosis combined with apropriate treatement can change the prognosis.

Introduction:

Malignant tumors of the parotid gland are reported to be rare during childhood. Sarcomas account for < 1.5% of malignant tumors of the parotid gland [1-3] . Rhabdomyosarcomas is one of the more common sarcomas of the parotid region occurring during childhood and adolescence, but overall its incidence remains rare [1-2] , The parotid localization remains the most frequent, followed by that of the submandibular gland and exceptionally accessory salivary glands [4]. It is a high-grade malignancy tumor. It is characterized by its locoregional aggressiveness, its metastatic evolution and its unfavorable prognosis. [3-5] As a result, information on the clinical presentation, management, and outcome of patients with RMS in the parotid region is based on small patient series or case reports [1-2-4-5] covering adults with two histological types of parotid tumors, as well as children [1-4] or report Consider patients with parotid tumors and patients with Rhabdomyosarcomas in other head and neck regions. [5-6] Based on our case report, we propose to review the data in the literature.

Case Report :

We reported a case of A 8-year-old child, with no medical history, consulted for a swelling of 9 to 10 cm in the long axis of the left parotid region, associated with complete ipsilateral facial paralysis developed for 3 months (Figure 1) . The Examination of the oral cavity revealed bulging of the soft palate and the inner side of the left cheek and the examination of the ipsilateral external auditory canal revealed an externalization of the mass through the canal which completely obstructs it 3 adenopathy’s were found in the examination of lymph nodes submental, submandibular and high carotid jugular 1 to 2 cm in diameter. 2Our patient benefited of a facial CT scan that showed parotid tumor with significant locoregional extension medially to parapharyngeal space, outside pushes back the left auricle, anteriorly and below fills the infratemporal fossa , further forward it comes into contact with the retromolar trigone, behind arrives at the pre vertebral space , with no bone lysis (Figure 2) The biopsy revealed an alveolar rhabdomyosarcoma whose macroscopic appearance was that of a brownish tumor with necrotic hemorrhagic areas. Microscopic examination showed that this tumor had an alveolar arrangement, the connective tissue was organized into a fibrillar stroma forming connective partitions delimiting closed or communicating cells. The tumor was classified T1BN1M0 group II ; Given the locally advanced nature of the disease , the patient was referred to the hematological department for chemotherapy and benefited from Ivado than Iva protocol, than the patient underwent surgery in our department by a left total parotidectomy with preservation of the facial nerve and left lymph node dissection of the territory IIA+ IIB with no tumoral residu in the anatomopathological exam, than he was referred for post-operative radiotherapy. 

Discussion:

Salivary gland carcinomas are rare in childhood. A survey of salivary tumors from the Armed Forces Institut of Pathology [5] revealed that 1.3% of benign and 3% of malignant salivary gland tumors occurred in children [6,7]. Rhabdomyosarcoma represents 13 to 18% of head and neck tumors [8,9] and less than 1% of salivary gland cancers [10]; However, its exact frequency remains difficult to determine given the rarity of cases and the heterogeneity of the populations studied. In a series of 168 childhood salivary gland cancers, Krull’s et al. [11] reported six cases of rhabdomyosarcoma, i.e., 3.5%. Luna et al. [20] reported two cases of rhabdomyosarcoma out of 11 cases of primary sarcoma of the salivary glands. The largest published series of salivary rhabdomyosarcomas included three to 22 cases [12,13,6,14] The parotid gland is the most frequent initial site of rhabdomyosarcoma before the submandibular and sublingual glands. Involvement of the accessory salivary glands remains exceptional [15]. Rhabdomyosarcoma is a high-grade malignancy tumor that affects subjects of all ages with a higher frequency in the first two decades of life, with, however, very broad extremes [16,6,17,18] Parotid rhabdomyosarcoma usually presents as painful swelling of the parotid gland that rapidly increases in size [19,18]. Facial paralysis is a frequent sign, testifying to the aggressiveness and degree of tumor extension. CT scans and magnetic resonance imaging (MRI) of the parotid are an essential contribution in terms of exploration of the parotid gland and evaluation of tumor extension to neighboring structures [20,21 ]. MRI seems to perform better with a sensitivity greater than 95% and a specificity greater than 75% [21]. A staging assessment combining pulmonary, hepatic and bone imaging is mandatory before any therapeutic decision. There is no universally accepted classification. Several are used, they are generally addressed to rhabdomyosarcomas without taking into account the localization [22–23]. Because of the aggressive nature of this tumor, treatment combines surgery, radiation therapy, and chemotherapy. Indications and relevance depend on classification, resection quality, and anatomic pathology findings; surgery is the cornerstone of treatment. It includes partial or total parotidectomy, with or without facial nerve preservation, according to the Gustave Rousey Institute classification, which is stage I and II cases and first-line treatment classification according to IRS group I and II cases (Intergroup Rhabdomyosarcoma study)[ 24,23], radiotherapy is indicated for incomplete resection and/ or histological lymph node invasion, and the radiation field must include the parotid gland where the tumor is located and the cervical-subclavian lymph node region (if involved).For persistent tumors and/or lymph node invasion with capsular rupture, a dose of 60 to 70 Gray is recommended. Due to their activity on salivary gland tumors and sarcomas [25,5,26];Adjuvant chemotherapy could improve local control and survival rates, but this remains to be demonstrated. Neoadjuvant chemotherapy could find its interest in locally advanced and/or inoperable tumors (stage III of the classification of the Gustave-Rousey Institute and group III of the IRS) by making them accessible to cardiological surgery. Salivary rhabdomyosarcomas have a tendency to local recurrence, the time to onset is on average nine months [23]. Pulmonary, hepatic and bone metastases are frequent, tumor dissemination can also occur towards the cerebrospinal fluid after invasion of the meninges. The time to onset is on average nine to 36 months [27]. Survival rates are variable. From 22 cases, Pappas et al. reported a twoyear disease-free survival rate of 63% after chemotherapy, radiotherapy and surgery [13], whereas Flammant et al. reported an overall survival rate of 68% and five-year disease-free survival of 53% [14]. For Cullender et al., five-year survival is 60% in the case of chemotherapy and radiotherapy [19].The stages or groups of classifications are major prognostic factors since in the IRS study, the five-year survival rates for groups I to IV were 83, 70, 52 and 20% respectively [28]. ; According to the Gustave-Rousey Institute, the five-year survival rates for stages I and II, III and IV were respectively 80, 53% and almost 0% [13,23]; Other prognostic factors have been analyzed, in particular the histological type: the more differentiated the tumor, the better the prognosis, the three-year survival rate is 60% in the botryoid forms and 40% for the for- my embryonic and alveolar. Due to more frequent lymph node invasion, the latter form has a 50% prognosis compared to 17% for the other forms [29]. The most important unfavorable prognostic factors for Cullender et al. are age (55% five-year survival rate for children under seven years old and 33% for children over seven years old), alveolar type, and tumor size greater than 5 cm [19].

Conclusion:

Rhabdomyosarcoma (RMS) is one of the more common sarcomas of the parotid region occurring during childhood and adolescence, but overall, its incidence remains rare AND often have an unfavorable prognosis. Improving results requires an early diagnosis and multidisciplinary management based on the results of multicenter trials. The inclusion of these patients in trials must be systematic due to the rarity of cases.

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