A 65-year-old lady from Syrian descent was referred to our institution in September 2014 for painless rapidly enlarging mass of the right cheek, which she noted only for 2 months prior to presentation. Relevant history included an early stage right breast invasive ductal carcinoma diagnosed 6 years earlier and treated by a lumpectomy with ipsilateral axillary lymph nodes dissection, followed by 6 cycles of adjuvant chemotherapy with CMF (cyclophosphamide, methotrexate, and 5-fluorouracil), focal radiotherapy to the chest wall and right axilla, and subsequent hormonal manipulation with letrozole for 5 years.\nThe patient was disease-free for the following 6 years until a growing right cheek mass led her to seek medical advice.\nPhysical exam revealed a palpable firm, nontender, nonmobile right inferior parotid mass of 2 cm at the level of the angle of the mandible. The right corner of the mouth dropped with asymmetry that increased with facial expression, thus indicating right mandibular branch palsy. The rest of the exam did not reveal any palpable cervical, supraclavicular, or axillary lymph nodes on both sides. Fibroscopy was done and was normal.\nContrast enhanced MRI scan of the neck revealed the presence of a 2 cm ill-defined mass of the right parotid gland at the inferior border, hypointense on T1 and mild hyperintense on T2 with moderate enhancement after gadolinium injection. No cervical lymphadenopathy was detected. Fine needle aspiration biopsy (FNAB) of the parotid mass revealed the presence of malignant cells of breast origin. Staging FDG-PET CT scan was obtained showing accumulation of 18-FDG in the right parotid and ruled out other distant or locoregional metastases ().\nA total parotidectomy was subsequently done with preservation of all facial nerve branches. However, the dissection of the mandibular branch was done with probable remnant of tumor cells on the nerve. The retroauricular vein was sacrificed because of direct invasion by the tumor. The anatomic pathology report confirmed the secondary nature of the tumor (of breast origin) invading the parotid parenchyma with perineural and perivascular invasion (). Although immunocytochemistry was not done on the FNA sample and was not needed for diagnosis, immunostaining with anti-estrogen receptor (ER) antibodies was performed on the final surgical pathology specimen and further supported the diagnosis as the tumoral cells were ER positive (). GATA3 immunostaining, a specific marker for breast cancer, was also done confirming the breast origin of the tumor ().\nThe patient tolerated well the procedure and was referred for adjuvant radiotherapy.
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.