In April 2020, a 69-year-old man presented with a swelling of the right parotid and developed 11 years ago without known etiology. The swelling in the front of the right ear has increased rapidly with pain from the past four months. On April 22, 2020, an ultrasound of the parotid gland showed solid space with multiple swollen lymph nodes of the right parotid gland. On April 27, 2020, the patient underwent a percutaneous core biopsy for the swelling of his parotid gland. On April 29, 2020, pathological examination of the right parotid gland revealed a malignant tumor (right parotid gland), and a further diagnosis was made by immunohistochemistry. Results of immunohistochemistry (Fig. 1) were as followed: P63 (+), CK5/6 (+), CK7 (+), Cam5.2 (+), Vimentin (+), Ki67 (+, 70%), S-100 (-), CEA (-), and EMA (+). These results were consistent with the diagnosis of adenocarcinoma. Physical examination showed an inflamed anterior mass of the right ear and multiple swollen lymph nodes of the right parotid gland. On April 23, 2020, chest computed tomography (CT) scan displayed the following results (Fig. 2) : 1. multiple nodules of both lungs and considering the possibility of transfer, 2. bilateral emphysema: mild bronchiectasis of both lower lungs, 3. double lung hypostatic effect, 4. bilateral pleural local thickening, 5. multiple lymph nodes in mediastinum and bilateral hilar with no obvious swelling, 6. aortic and coronary atherosclerosis, and 7. low-density nodule on the left lobe of the thyroid. On April 23, 2020, computed tomography (CT) of parotid gland scan (Fig. 3) showed a space-occupying the right parotid gland and multiple peripheral swollen lymph nodes with malignant signs. The results suggested stage IV parotid gland adenocarcinoma cancer with lung metastases, and there was no opportunity for surgery. As first-line treatment, he received three courses of immunotherapy combined with chemotherapy. The medication regimen was as follows: The 1th cycle was initiated on May 1, 2020, pembrolizumab (venous 60 min) 200 mg Day 1; paclitaxel 400 mg (twice) Day 1, 7. And repeated every 3 weeks. The main adverse reaction during treatment was rash, for which dexamethasone was administered. After three treatment cycles, the condition of the patient improved, and surgery was considered. The patient underwent parotidectomy in October 2020. In postoperative pathology, no tumor cells were discovered. Regular outpatient re-examinations have been performed following surgery.