Efficacy of Immunotherapy Combined with Antiangiogenic Therapy in Treatment-Failure Patients with Advanced Carcinoma Ex Pleomorphic Adenoma of the Submandibular Gland: A Case Report

Carcinoma ex pleomorphic adenoma (Ca ex PA) is a rare malignant tumor that arises from a primary or recurrent benign pleomorphic adenoma (PA). Ca ex PA has an aggressive behavior and poor prognosis. To date, there are no standardized therapeutic methods. Herein, we reported a case of a 57-year-old Chinese female with Ca ex PA of the submandibular gland. After surgery, cervical lymph nodes recurred, and multiple distant metastases were detected. During the treatment, she received multiple chemotherapies and radiotherapy but suffered from multidrug resistance and repeated disease progression. Hence, PD-1 inhibitor (sintilimab), in combination with anlotinib, was administered, which resulted in better control of pulmonary metastases compared to the other treatment regimens. This provided an alternative treatment option for Ca ex PA of the submandibular gland patients with failed multiple therapies.

Mixed response and mechanisms of resistance to larotrectinib in metastatic carcinoma ex pleomorphic adenoma of the parotid harboring an NTRK2 fusion: A case report

INTRODUCTION

Standardized systemic treatment options are lacking for carcinoma ex pleomorphic adenoma, which is a rare and aggressive tumor primarily found in salivary glands.Here we report the case of a 63-year-old male with carcinoma ex pleomorphic adenoma of the left parotid and parapharyngeal space harboring a neurotrophic receptor tyrosine kinase (NTRK) 2 fusion who was treated with a small molecule inhibitor that targets the tropomyosin receptor kinase (TRK) proteins. To the best of our knowledge, no similar case has been described in the literature so far.

PATIENT CONCERNS

After multiple surgical resections and radiotherapy for localized cancer disease over several years, our patient again developed an increasing swelling and pain around the left ear and numbness of the left half of the face.

DIAGNOSIS

Magnetic resonance imaging and positron emission tomography/computed tomography scans showed tumor recurrence in the left parotid, below the left ear, and in the parapharyngeal space, as well as metastases of the lungs and cervical lymph nodes. As data on the efficacy of systemic therapies for inoperable carcinoma ex pleomorphic adenoma are scarce, we performed a next-generation sequencing that revealed the presence of a hitherto unknown NTRK2 fusion.

INTERVENTIONS

Treatment with the TRK inhibitor larotrectinib was initiated, which induced rapid symptom improvement. However, part of the tumor had to be removed shortly afterwards due to local progression. Molecular testing did not demonstrate any alterations accounting for resistance to larotrectinib, with maintenance of the NTRK2 fusion.

OUTCOMES

Three months later, imaging confirmed mixed response. While the reason for this remains unknown, the patient is in good condition and continues to receive larotrectinib.

CONCLUSION

It remains unclear why our patient showed mixed response to larotrectinib and further studies are needed to explore other possible mechanisms of resistance.

[Clinical analysis of salivary malignant pleomorphic adenoma--a report of 95 cases]

BACKGROUND & OBJECTIVE

Malignant pleomorphic adenoma is rare with extensive location, which makes it difficult to evaluate the efficacy of the treatments. This study was to summarize the clinical features of salivary malignant pleomorphic adenoma, and thus to explore the treatment principle and efficacy of the treatment.

METHODS

Clinical data of 95 salivary malignant pleomorphic adenoma patients, treated in Cancer Center, Sun Yat-sen University from May 1970 to Oct. 2000, were analyzed retrospectively. The overall cumulative survival rate was estimated using life table method by SPSS10.0 software. Survival curves were compared with Gehan method.

RESULTS

The 5-, 10-, and 15-year overall survival rates of the 95 patients were (64.9+/-4.9)%, (56.3+/-5.4)%, and (47.8+/-6.1)%, respectively. The 5-and 10-year disease-specific survival rates for the patients received surgery (51 cases), surgery plus radiotherapy (35 cases) were 76.1%, 63.7% and 69.9%, 50.8%, respectively, but the 5-and 10-year disease-specific survival rates for the patients received radiotherapy only, chemotherapy only and radiochemotherapy (4 cases) were all 0.

CONCLUSIONS

Surgery or surgery-dominated multi-modality are the principal treatment modalities for salivary malignant pleomorphic adenoma. The efficacy of surgery and surgery plus radiotherapy is better than non-surgery treatments.

Vinorelbine treatment of recurrent salivary gland carcinomas

Twenty patients (13 males, 7 females, median age 61 years, range 27-74) with recurrent adenocarcinoma-like tumors of major (10 patients) and minor (10 patients) salivary gland origin (13 adenoid cystic carcinoma, 5 adenocarcinoma, 1 malignant mixed tumor, 1 undifferentiated carcinoma) were treated with vinorelbine at the dose of 30 mg/m2 i.v. weekly. Sixteen patients had been previously treated with surgery + radiation, 3 with surgery + radiotherapy + Novantrone and 1 with radiotherapy alone. Nine patients had local recurrence, 2 local relapse + metastasis and 9 metastasis alone. Site of metastases are: lung (7), bone (1), lung + bone (2), lung + bone + lymph-node + skin (1). Overall 174 courses were given (median 9, range 6-19). Responses were: PR in 4 patients (20%) with a median duration of 6 months (3-9), 9 NC (45%) with a median duration of 3.5 months and 7 PD (35%). The median survival time was 10 months for PR/NC patients, 4 months for non-responders. Median overall survival was 7 months. Vinorelbine has a moderate activity in these very advanced cases.

Chemotherapy for salivary gland cancer

Because of the scarcity of such lesions, little is known about the efficacy of chemotherapy for advanced salivary gland cancers. Although surgery and irradiation are the mainstays of treatment, patients with recurrent tumors and those with unresectable or metastatic cancer are not candidates for this usual approach. Ten patients with recurrent, metastatic, or unresectable salivary gland tumors were treated with combination chemotherapy, primarily with cisplatin, doxorubicin hydrochloride (Adriamycin), and cyclophosphamide, or cisplatin with 5-fluorouracil. In patients whose tumors exhibited no response, second-line drugs were used. The overall response rate was 50%--with one complete response--but the duration of response was short. This report contributes to the growing data base that demonstrates definite chemosensitivity of these tumors. To date, 116 patients have been reviewed. Adenocarcinoma-like cancers respond best to cisplatin, doxorubicin hydrochloride, and 5-fluorouracil. High-grade mucoepidermoid carcinoma may show a sensitivity similar to that of squamous cell carcinoma. Multi-institutional protocols need to be developed to assess the roles of adjuvant and palliative chemotherapy in the treatment of salivary gland cancer.