CASE DESCRIPTION
An 80-year-old female patient presented to our department with a chief complaint of swelling over the right side of the face in the past 1 year. The swelling gradually increased in size within 10 months. The patient noticed a rapid increase in swelling over the last two months which was associated with intermittent pricking pain. The patient also reported having difficulty in opening her mouth and a lack of sensation in the lower lip on the right side. She gave a history of exfoliation of all her teeth by the age of 60, and there was no history of discomfort or swelling, which made her visit a health practitioner.
On extra oral examination, a solitary oval-shaped swelling was noted along the right posterior body and ramus of the mandible measuring approximately 5 cm X 3 cm in the greatest dimensions, roughly oval in shape with a smooth surface. The skin overlying the swelling appeared to be smooth and tense. On palpation, the swelling was warm, tender, firm to hard in consistency, and had a smooth surface and well-defined margin. Lymph nodes were not palpable [Figure 1].
Intra orally, a solitary irregularly shaped swelling measuring approximately 4 cm X 2 cm in its largest dimensions was noted along the posterior third of the lower right edentulous alveolar ridge causing expansion of the alveolus bucco - lingually. The swelling was pale pink in color and had a lobulated surface. Obliteration of buccal vestibule and tense buccal mucosa were also noted [Figure 2]. On palpation, the swelling was afebrile, firm with areas of tenderness over the superior aspect of the swelling.
A provisional diagnosis of ameloblastoma was made considering the history, age, aggressive nature of the tumour, and location. Differential diagnoses of malignant non-odontogenic tumours, and metastatic tumours to the jaw were also considered. Basic investigations were undertaken, including hematological parameters, renal function tests and liver function tests, an orthopantomogram (OPG), and CT scan.
Panoramic radiography revealed a large radiolucent lesion, located over the right side of the mandible involving the entire ramus and body up to the right para-symphysis region. It measured approximately 4 cm X 7 cm roughly oval in shape with an epicenter at the ramus of the mandible and had a partially corticated border. The internal structure appeared to be completely radiolucent. Expansion and thinning of the anterior border, and thinning of the posterior and inferior border of the mandible were evident with few areas of perforations at the anterior border along the ascending ramus of the right side of the mandible [Figure 3].
A computed Tomography scan demonstrated a uniformly expansile, oval-shaped osteolytic lesion around the right side of the mandible, involving the ramus, coronoid, and body, measuring approximately 4 cm X 4.84 cm X 7.5 cm in its largest dimension. The internal structure appeared to be hypodense, with radiodensity equivalent to soft tissue. The lesion had caused expansion, thinning, and loss of cortex in bucco-lingual, antero-posterior, and superior-inferior directions. Irregular bone destruction with bony spicule was noted over the body of the mandible in relation to the para symphysis region. The inferior alveolar canal could not be visualized due to lesion invasion [Figure 4].
Screening CT of the thorax and USG abdomen revealed no evidence of any lesion. Liver function tests and renal function tests showed normal values.
On histopathological evaluation, Hematoxylin and eosin-stained section showed a nonencapsulated tissue stroma with proliferating tumour cells arranged in solid sheets and cords. The tumour cells were uniformly arranged round cells with round oval-shaped nuclei, scanty pale cytoplasm, and showing abundant mitotic figures. Spindle-shaped cells arranged in pagetoid fashion were also noted with few areas showing blood vessels along with extravasated RBCs, and focal areas of bony trabeculae infiltrated by tumour cells [Figure 5].
The immunohistochemical staining was performed. The percentage of the tumour marker Ki-67 was positive and the proportion was assessed to be 90%. Additionally, the markers cytokeratin (AE1/AE3), synaptophysin, and chromogranin A were found to be positive. Hence, a diagnosis of small cell neuroendocrine carcinoma was made.
Resection and chemo and radiotherapy were planned for the patient. But patient passed away due to post covid complications within one month of diagnosis; hence definitive treatment could not be given.