Oral Soft Tissue Sarcomas Overview

Oral Soft Tissue Sarcomas

• Rare in the oral and maxillofacial region
• Represent 5% of all cases, the majority are found in extremities
• Occur most often in patients around 40 years old
• Often present as painless masses that grow rapidly
• Common sites include the face, orbit, and nasal cavity
• Intraorally, the palate is a frequent location

Embryonal Rhabdomyosarcoma

• Characterized by alternating hypercellular and hypocellular areas with myxoid collagenous stroma
• Densely cellular subepithelial zone composed of primitive small cells with hyperchromatic nuclei and mitotic activity
• Rhabdomyoblasts are typically seen in the hypocellular foci
• Resembles stages of skeletal muscle embryogenesis
• Rhabdomyoblasts are plump cells with eccentric nuclei and dense eosinophilic cytoplasm
• Elongated strap cells display eosinophilic cytoplasm and cross striations
• Tadpole cells (unipolar) are also observed

Alveolar Rhabdomyosarcoma

• Features nests and sheets of primitive small round cells with abundant eosinophilic cytoplasm
• Noncohesive cells floating in empty spaces create a characteristic alveolar pattern

Pleomorphic Rhabdomyosarcoma

• Demonstrates sheet-like growth of pleomorphic round to spindled rhabdomyoblasts

Treatment and Prognosis of Rhabdomyosarcoma

• Treatment usually involves local surgical excision followed by multiagent chemotherapy (vincristine, actinomycin D, and cyclophosphamide)
• 5-year survival rates vary depending on the subtype:
  • Embryonal NOS: 66-72%
  • Botryoid (type of embryonal): 95%
  • Alveolar: 44-53%

Lymphoma

• A type of cancer that affects the lymphatic system
• Two main types: Hodgkin lymphoma and Non-Hodgkin lymphoma
• Distinguished from leukemia by its primary involvement of lymph nodes
• Unlike leukemia, which affects blood and bone marrow

Hodgkin’s Lymphoma

• Almost always begins in lymph nodes, any group can be affected
• Most commonly presents in cervical and supraclavicular nodes
• Shows a male predilection and a bimodal age distribution, peaking between 15-35 years and after 50 years
• Typically presents as enlarging, nontender, discrete masses in one lymph node region
• If untreated, it spreads to other lymph node groups and eventually involves the spleen and extralymphatic tissues (bone, liver, lung)
• Oral involvement is rare
• Systemic symptoms (weight loss, fever, night sweats, and generalized pruritus) may occur in 30-40% of patients
• The absence of these symptoms is associated with a better prognosis

Histopathology of Hodgkin’s Lymphoma

• Normal nodal architecture is disrupted by a diffuse infiltrate of large, atypical neoplastic lymphoid cells
• These atypical cells are known as Reed-Sternberg cells
• Reed-Sternberg cells are typically binucleated (“owl-eye” nuclei) or multinucleated (“pennies on a plate”) with prominent nucleoli

Treatment of Hodgkin’s Lymphoma

• Usually involves radiotherapy and chemotherapy

Non-Hodgkin lymphoma (NHL)

• Classified primarily as B cell lymphomas (more common) or T cell lymphomas
• Typically develops in lymph nodes, but 40-50% arise in extranodal sites, including the oral cavity
• Oral involvement is often an extranodal manifestation

Histopathology of NHL

• Characterized by proliferation of lymphocytic-appearing cells with varying degrees of differentiation, depending on the specific lymphoma type

Oral Manifestations of NHL

• The tumor can develop in the oral soft tissues or centrally within the jaws
• Soft tissue lesions appear as nontender, diffuse swellings, affecting the buccal vestibule, posterior hard palate, or gingiva
• Lesions can be erythematous or purplish, and may or may not be ulcerated