A 65-year-old male presented with an eight-week history of a left-sided neck mass. The patient described a mass, which was initially the size of a golf ball, but grew rapidly. By the second month, it caused significant pain, dysphagia, and dyspnea, prompting an urgent visit to the hospital. Pertinent physical examination findings at presentation included a firm, large 20 cm mass which occupied the entire left neck. The mass crossed the midline, displacing the trachea to the right side.\nThe patient was admitted and a computed-tomography (CT) scan was performed (Figure ) revealing a large (9.5 cm x 12.9 cm x 21 cm), trans-spatial, infiltrative, mixed solid and cystic mass involving the left carotid, parotid, masticator, parapharygeal, and prevertebral spaces. The tumor extended through the left thyrohyoid membrane and involved the submucosal surface of the oropharynx, hypopharynx, and larynx and crossed the midline via the retropharyngeal space, insinuating between the right thyroid lobe and cricoid cartilage and extended inferiorly into the anterior and superior mediastinum. There was also severe narrowing of the supraglottic airway and rightward deviation of the entire laryngeal axis. No obvious erosion of adjacent osseous structures, hyoid bone, laryngeal cartilage, or tracheal cartilaginous rings was appreciated.\nA tracheostomy tube and a percutaneous feeding tube were placed. Additionally, a biopsy of the mass was performed. This revealed a myxoid sarcoma composed of cords, clusters, and strands of cohesive epithelioid cells within a large amount of myxoid matrix. Pale vesicular nuclei and mitotic figures were readily identified within the cells. Immunohistochemistry (IHC) stains were negative for brachyury, cytokeratin, smooth muscle actin, and S100. Based on the pathologic appearance of the cells and IHC features, the diagnosis of extraskeletal myxoid chondrosarcoma with prominent cytoplasmic vacuolization was established (Figure ).\nThe tumor was considered to be unresectable due to its locally advanced nature. The patient was recommended to receive concurrent chemotherapy and radiation. Informed patient consent was obtained. He was treated with eight weekly cycles of doxorubicin (10 mg/m2) with concurrent image-guided, intensity modulated radiotherapy to a dose of 7000 centigray (cGy) in 35 fractions given over the course of seven weeks (Figure ).\nDuring treatment, he was noted to have a drastic response to therapy, necessitating re-simulation and re-planning of radiotherapy after 4400 cGy (Figure ). At the completion of the concurrent therapy, the patient was noted to have a remarkable clinical response with a significant improvement in speech and swallowing and in tumor size and pain.\nHe tolerated therapy fairly well and completed the planned treatment with no breaks. He experienced the expected side effects of grade 3 mucositis and grade 3 radiation dermatitis (Common Terminology Criteria for Adverse Events version 4.0), which were managed with opioid analgesics, topical ointments, and silver sulfadiazine cream. Near the end of the therapy, he was suspected to have superimposed cellulitis that was successfully treated with antibiotics.\nDuring the course of the concurrent chemoradiotherapy, molecular profiling (Caris Life Sciences, Phoenix, AZ) was performed on the patient’s tumor for biomarkers of drug response. High expression of TLE3 and negative IHC staining for PGP and TUBB3 suggested a potential benefit for docetaxel, paclitaxel, or nab-paclitaxel. IHC staining was negative for ERCC1, suggesting a potential benefit for carboplatin, cisplatin, or oxaliplatin.\nOne month after the completion of therapy, the patient is recovering as expected from the acute toxicity of therapy and is demonstrating a complete clinical response and an excellent radiographic response (Figure ). Further chemotherapy with carboplatin and paclitaxel is planned given the results of molecular profiling.
A 13-year-old male presented with a rapid enlarging painless diffuse mass located at the right midface and parotid region over the last 6 months. Slight asymmetry of the right commissure, trismus and mandibular asymmetry were evident on initial examination. There were no evidences of regional or distant metastasis. Past medical history included a previous surgical treatment attempt in his native country Honduras, three months prior to his referral (Fig. A). T1 weighted MRI showed a large hyperintense mass measuring 7 x 5 cm, located centrally at the right masticator space with extention into the mandibular ramus, masseter and pterigoyd muscles, parotid gland and parapharyngeal space. Contrast T2 weighted MRI exhibited a high signal with a multinodular and infiltrative pattern (Fig. B).\nAn incisional intraoral biopsy was performed under local anesthesia. The histopathological examination revealed multiple nodules containing tumor cells, immersed in an abundant myxoid stroma separated by fibrous septae. The tumor cells varied in shape from round to elongate, most displaying abundant eosinophilic cytoplasm and round to ovoid excentrically located nuclei, which showed homogeneously distributed chromatin and inconspicuous nucleoli. Other cell types were recognized, mainly spindle, epithelioid and lipoblast-like cells (Fig. ). The mitotic rate was low, averaging two mitotic figures per 10 high-power fields. Periodic acid-Schiff (PAS), with and without prior diastase digestion, demonstrated that the granular cytoplasmic material was glycogen. Immunohistochemical analysis (), showed positivity for vimentin, neuron-specific enolase (NSE), and chromogranin; whereas AE1/AE3, epithelial membrane antigen (EMA), S-100, desmin, muscle-specific actin (HHF35), CD57, Glucose transporter type 1 (Glut-1), synaptophysin, p53, p63, glial fibrillary acidic protein (GFAP), and podoplanin (D2-40) were negative. The Ki-67 labelling index was 42% after evaluation of 1000 cells per five high-power fields (Fig. ). Fluorescent in situ hybridization was not performed; however, the histomorphological and immunohistochemical findings supported a final diagnosis of EMC.\nThere were no evidences of regional or distant metastases, and the patient was treated with en-bloc surgical resection, including ipsilateral hemi-mandibulectomy, total parotidectomy with facial nerve dissection, neck dissection level I to IV and reconstruction with a mandibular plate and major pectoralis flap. Macroscopically, the specimen measured 8 x 6 x 5 cm consisting of an irregularly shaped mass attached to the mandibular ramus, with a multilobular and gelatinous rubbery tissue. Focally, the tumor was present in one surgical margin, immediately anterior to the mandibular condyle. Microscopic evaluation revealed the same histopathological features found in the incisional biopsy. The patient received adjuvant radiotherapy but died after 1 year of follow-up due to complications of locoregional tumor dissemination to the skull base.