Article Type : Review Article
Authors : Shunmugavelu K and Javid Shaikh SM
Keywords : Lymphomas; Neoplasms; Tumors; Salivary gland
Head and neck neoplasms are uncommon in pediatric patients
and affect 12% of children. Head and neck masses may occur from a variety of
causes, including infection such as enlarged lymph nodes, congenital cysts or
masses that formed during development, or tumors.
Head and neck neoplasms are uncommon in pediatric patients
and affect 12% of children. Head and neck masses may occur from a variety of
causes, including infection such as enlarged lymph nodes, congenital cysts or
masses that formed during development, or tumors. Approximately 1 in 10 childhood neoplasms involve
the head and neck region. The children with diseases of the head and neck
region are most frequently identified by pediatricians and
otorhinolaryngologists. The presenting symptoms in the children with head and
neck neoplasm are indistinct, which makes the diagnosis difficult. The tumor size, primary site of involvement, etiology, and
presence of regional or distant metastases determines the prognosis of head and
neck tumors. The early diagnosis of the tumors favors good prognosis. The most common pediatric head and neck malignancies are lymphomas (27%), neural tumors (23%),
thyroid malignancies (21%), soft tissue sarcomas (12%), nasopharyngeal
carcinoma, skeletal malignancies, and salivary gland malignancies.
Lymphomas are characterized by the proliferation of mature
lymphoid cells and are the heterogeneous group of malignant tumors of the hematopoietic
system [1]. It is the second
most common malignancy in the world [2]. The diagnosis of lymphoma is mainly based on
the histhopathological examination of tissue from enlarged lymph nodes. They
are broadly classified into Hodgkin’s lymphoma and Non-Hodgkin’s lymphoma.
Non-Hodgkin lymphoma is
the fourth most common malignancy in children [2]. It most commonly occurs in
children older than 10 years but can also occurs in children less than 5 years [2].
Sixty percent of lymphomas are Non-hodgkin type.
Typical symptoms can
include painless swelling of lymph nodes in neck, chest, abdomen or groin,
fatigue, occasionally such as fever >?38?°C, night sweats and weight loss
(>?10% within 6?month), susceptibility to infections and changes in the
hemogram. Other symptoms include abdominal pain, diarrhea, dyspnea, and
dysphagia [1-4].
Treatment depends on type and staging. It includes
chemotherapy, radiation therapy, surgery, use of monoclonal antibodies, high
dose chemotherapy and supportive care [4].
Hodgkin lymphoma is
characterized by the presence of typical multinucleated Reed-Sternberg cells,
mononucleated cells known as Hodgkin Reed-Sternberg cells and they are derived
from B cells. It affects 6 % of the pediatric population and it occurs most
commonly in male [5,6].
Most common symptoms
include painless adenopathy in supraclavicular or cervical areas while some
children show B symptoms – unexplained fever, drenching night sweats and weight
loss [6,7].
Treatment includes
chemotherapy, radiotherapy, and surgical excision of tumors. The risk of
relapse is high, and the primary complication is development of secondary
malignancy which remains a cause of concern [6].
Rhabdomyosarcoma, the mesenchymal malignant neoplasm with
skeletal muscle differentiation is the most common soft tissue sarcoma in the
pediatric population [8]. It
most commonly occurs in 1 to 4 years old and least common in children older
than 10 years of age [9]. In head and neck region, orbit is the most site of involvement and
in the oral cavity, the tongue followed by the soft palate, hard palate, and
buccal mucosa are most are most involved. Etiology of Rhabdomyosarcoma is
unknown but may be caused due to in utero radiation exposure,
accelerated in utero growth, low socioeconomic status, and parents using
recreational drugs during pregnancy. It presents as poorly circumscribed,
white, soft, or firm, infiltrative masses. The tumor at the time of diagnosis
is around 5cm in diameter [10].
Clinical manifestations
of RMS include small cutaneous nodule on the face or an extensive fast-growing
facial swelling, trismus, paresthesia, facial palsy, and nasal discharge. The
pain, paresthesia, loss of teeth, and trismus are caused due to advanced tumor
stage, infiltrative growth, and tumor location.
The treatment of RMS is a
multidisciplinary approach, surgical removal of the tumor followed by
chemotherapy with or without radiotherapy since RMS tends to metastasize to
bone marrow. Prognosis
of RMS is poor when compared to other oral soft tissue malignant lesions [9].
Nasopharyngeal
carcinoma (NPC) is a malignant neoplasm arising from the epithelial cells
lining the nasopharynx and rare malignancy in the pediatric age group
[11-13]. Nasopharyngeal
carcinoma affects around 5% of pediatric population [11]. NPC is a rare tumor in children
younger than 10 years of age, and the incidence rises gradually with age of the
patient. It is a common head-and-neck tumor seen in adults [13]. The median age of nasopharyngeal
occurrence in children is 13 years with male predominance [11].
The genetic
susceptibility, environmental factors such as exposure to chemical carcinogens,
and infections with Epstein–Barr virus (EBV) are etiological factors related to
NPC. The clinical symptoms of NPC include epistaxis, nasal obstruction,
deafness, tinnitus, headache, and neck swelling. Bone erosion at the skull base
region with or without affecting cranial nerves can also been seen [13].
The standard treatment
for NPC is chemotherapy with surgery [13]. Treatment related toxicity
includes mucositis, skin erythema, xerostomia,
neck fibrosis, dental caries, trismus, hypopituitarism, stunted growth, and
hypothyroidism [12].
Thyroid carcinoma is
rare in the pediatric population, children more often present with aggressive
and advanced stage of disease. It occurs in the second decade of life with
female predominance (male female ratio is 1: 6) [14]. It is the 5th most common tumor
and affects around 6 % of the pediatric population [14,15].
Signs and symptoms are
thyroid nodule with asymptomatic neck mass, with or without cervical
lymphadenopathy, trouble breathing and hyperthyroidism [14]. In pediatric thyroid cancer
multiple nodules are present and they also have a higher risk of recurrence
than adults [14].
The treatment of choice is total thyroidectomy
along with radioactive iodine therapy and a near-total thyroidectomy is also
performed in some cases, in which a small amount of thyroid tissue near the
recurrent laryngeal nerve or superior parathyroid glands may be spared to
decrease the possibility of damage to adjacent structures
[14]. Pediatric patients
have better prognosis and significantly lower mortality rates than adults
[15].
Mucoepidermoid carcinoma (MEC) is the most common primary
epithelial salivary gland malignancy [16]. Mucoepidermoid carcinomas account
for 50% of malignant salivary gland tumors [18]. Most common in the parotid gland, only a few pediatric and
adolescence cases have been reported in minor salivary glands [17]. The
most common site for minor salivary gland tumors is the palatal region,
followed by buccal mucosa. It occurs around 10-16 years of age with female
predominance [16,17].
When the major
salivary glands and tongue are involved, pain, paresthesia, and difficulty with
swallowing are also present. Intraoral lesions appear as a localized fluctuant
nodule with a bluish or reddish-purple, smooth, mucosal surface. In some case
mucus may be discharged from the tumor through a small sinus tract. High grade
lesions may be quite firm along with ulceration, resorption of bone and
numbness of adjacent teeth [16].
Treatment for MEC is typically surgical resection. Complete
excision (superficial or total parotidectomy) with preservation of facial nerve
is the treatment of choice. Neck dissection should be considered when there is
clinical evidence of regional metastasis, high TNM stage, high histologic
grade, and involvement of regional nodes [18-20].
Neuroblastoma is the most common extracranial soft tissue
tumor affecting children less than 12 months of age and the second most common
neoplasm after Rhabdomyosarcoma. The tumor arises from primitive
neuroectodermal cells, which are derived from neural crest cells. Most cases
are caused by sporadic mutation, in recent studies autosomal dominant are
reported, with ALK and PHOX2B oncogenic mutations.
The palpable abdominal mass generalized bone pain, malaise,
fever, and irritability are the most common clinical presentation. Primary
cervical neuroblastoma should be ruled out in any child less than one year of
age with a persistent neck mass. Horner's syndrome was the most common
presentation in the head and neck neuroblastoma.
Diagnosis is usually made based on imaging and biopsy. Urine
catecholamines plays an important role in diagnosis. Neuroblastomata are
characterized by defective catecholamine synthesis. This leads to an
accumulation and excretion of the catecholamine metabolites homovanillic acid
(HVA) and vanillylmandelic acid (VMA). These levels are high in children with
neuroblastoma.
Treatment options for neuroblastoma are determined by tumor
stage, patient age, tumor location and resect ability, tumor histopathology,
and MYCN gene amplification. Surgery with clear margins is the important
prognostic factor. Multidrug chemotherapeutic regimens can be used in the
preoperative or postoperative setting.
Incidence of head and
neck neoplasms in the pediatric age group is rare but the incidence is
increasing. Awareness about the malignancies and careful follow up with proper
diagnosis in suspicious cases is mandatory so that proper treatment can be
provided to such patients and the risk of metastasis is reduced which in turn
helps to improve the prognosis. Therefore, it is important to have these masses
evaluated if they persist.