In October 2018, a 64-year-old man presented at the Department of Otolaryngology, Head and Neck Surgery, First Hospital of Jilin University, Changchun, Jilin Province, China with a painless mass below the right ear and complained of peripheral facial paralysis for a month. A physical examination found a 2.0 × 2.0 cm mass, with poor mobility, in the right parotid region. The accompanied peripheral facial paralysis on the right side was classified as House-Brackmann Grade III. Neck ultrasound identified a solid mass in the right parotid gland with enlargement of the lymph nodes in the gland and the right submandibular lymph nodes. Lung computed tomography (CT; ) demonstrated abnormalities in the upper and middle lobes of the right lung and intermediate bronchus, with obstructive pneumonia, as well as enlargement of the right hilar and mediastinal lymph nodes. The patient showed no symptoms of coughing, expectoration or haemoptysis.\nThe patient insisted on confirming the malignancy of the solid mass in the right parotid gland but refused to undergo preoperative needle biopsy. Intraoperative pathology confirmed a malignant tumour with metastatic potential. Thus, the right parotid gland and facial nerve were resected and selective neck dissection performed. Postoperative histopathological analysis demonstrated small cell carcinoma in the right parotid gland () with involvement of the right neck lymph nodes (one of eight). Bronchoscopy was performed and the pathological results were small cell carcinoma (. Immunohistochemical analysis of the postoperative pathological specimen indicated positive staining for pan-cytokeratin, CD56, chromaffin granule protein A, synapsin (Syn) and thyroid transcription factor-1 (TTF-1) (), partial positive staining of Ki-67 and cytokeratin 7, and negative staining for CD99, cytokeratin 5/6 and common leukocyte antigen (LCA). Immunohistochemical analysis of the bronchoscopy pathological specimen demonstrated positivity of pan-cytokeratin, CD56, Syn, TTF-1, partial positivity of Ki-67, but no staining of P40, cytokeratin 20, cytokeratin 5/6, vimentin and LCA, suggesting possible metastasis of small cell lung cancer to the parotid gland. Positron emission tomography (PET)/CT identified a hypermetabolic lesion in the right upper and middle lobes of lung and intermediate bronchus (), suggesting possible central lung cancer with distal obstruction and inflammation. Multiple lymph nodes were involved, and localized peritoneal thickening with hypermetabolism was observed under the right lobe of the liver, suggesting possible liver metastasis. Although hyperplasia, calcification and a hypermetabolic area were observed in the prostate under PET/CT, analysis of prostate-specific antigen in the serum and magnetic resonance imaging (MRI) showed no lesion.\nThe patient recovered well after the surgery and was scored 1 on the Eastern Cooperative Oncology Group performance scale. From postoperative day 15, the patient started to undergo six cycles of adjuvant chemotherapy with a combination of cisplatin + etoposide: days 1–3, 75 mg/m2 cisplatin intravenously + 100 mg/m2 etoposide intravenously; day 4, 100 mg/m2 etoposide intravenously; day 5, 50 mg/m2 etoposide intravenously; and the cycle was repeated every 20 days. Supportive therapy was also provided. No complications of the chemotherapy were observed after three cycles, treatment and follow-up are ongoing. Ethical approval was not required for this case report. The patient provided written informed consent for the publication of their data.
A 19-year-old woman with pain and swelling in her right parotid gland was referred to Shohada Hospital (Tehran-Iran) with no underlying diseases. She has complained of a mobile mass on the parotid region for a duration of 3 months. In her clinical examination, the oral mucosa and overlying skin were observed as intact with normal color. The patient's magnetic resonance imaging (MRI) indicated a high signal of a lobular-contoured, as a 4 × 2.5 cm solid mass lesion in the superior lobe of her right parotid gland (Figure ). A fine needle aspiration biopsy was performed by a maxillofacial surgeon and then a pathologic report indicated an unknown type of soft tissue malignancy. The primary diagnosis and the surgical treatment plan were discussed for the patient and a written consent was then obtained from her. At the operation session, following conducting the frozen-sections evaluation, malignant spindle cell tumor was diagnosed. Thereafter, a total parotidectomy was performed. As well, the gross examination of the specimen revealed a solid creamy mass with an almost well-defined border, invading the superficial lobe of the parotid gland. In addition, the permanent microscopic sections demonstrated a malignant neoplasm composed of fascicles of atypical spindle-shaped cells with large pleomorphic vesicular nuclei, prominent nucleoli, and clear-to-pale eosinophilic cytoplasm arranged in a storiform pattern (Figure ). Multinucleated giant cells and lymphocytic infiltration were observed as well. Notably, mitotic activity was about 4/10 HPF. By performing an immunohistochemically analysis, it was found that the atypical cells were HMB45 (Figure ) and S100 positive (Figure ). However, other markers such as Myo D1, Desmin, PanCK, and CK5/6 were negative. The microscopic feature along with IHC findings was consistent with the result of melanoma diagnosis.\nTo discover the primary origin of the recent melanoma lesion, a comprehensive past medical history was taken from the study case. As a result, we found that she had a history of congenital scalp pigmented nevus with no pathological consultation or any report of metastasis after 2 years (Figure ). Considering the possibility that the scalp lesion may be the origin of metastatic malignant melanoma, we suggested her to undergo excisional biopsy of the newly developed scalp lesion. In this regard, the patient was referred to the dermatology department for both consultation and performing the excisional biopsy operation. Thereafter, the newly formed scalp lesion was surgically removed. As well, the gross examination of the specimen showed safe border margins (0.6–1 cm) as well as a pigmented lesion in the center. Sections also demonstrated skin tissue with dissipated pigments from the epidermis to deep dermis. Moreover, the proliferation of atypical spindle cells scattered in the stroma was arranged from the superficial epidermis to hypodermis with vesicular nuclei and eosinophilic nucleolus (Figure ). Of note, the mitotic activity was about 1 in 10 HPF. In this patient, immunohistochemical staining showed the HMB45 intense positivity, but Ki67 was estimated as lower than 5%. Therefore, according to all these findings, the diagnosis of malignant melanoma was confirmed. After a month, she underwent parotidectomy due to swelling and pain in the left parotid gland. The histopathological report showed the same malignant melanoma. Thereafter, adjuvant chemotherapy and radiotherapy were performed for her during 6 and 4 sessions, respectively. She followed her disease by administrating complementary medicines too (homeopathy). After 18 months of follow-up, the lesion has not recurred and she has still been on a regular follow-up program.