Minimally invasive carcinosarcoma ex pleomorphic adenoma: A case report and literature review with cytohistological correlation

Salivary gland carcinosarcoma ex pleomorphic adenoma: a case report with molecular characterization

True malignant mixed tumors, also known as salivary gland carcinosarcoma (SCS), are uncommon yet highly aggressive lesions associated with a poor prognosis. These tumors exhibit a distinctive biphasic structure characterized by both epithelial and mesenchymal components. Recent research has shown that the majority of SCS cases stem from pre-existing pleomorphic adenomas (PAs), suggesting a stepwise developmental pattern. In this report, we present a case of a 73-year-old female with SCS and describe the clinical, radiographic, and pathologic observations. Notably, the SCS was associated with a residual PA. The SCS displayed a CTNNB1::PLAG1 gene rearrangement, providing a molecular basis for its origin from the PA. Further DNA genomic analysis exposed mutations in BAP1, PER1, and LRPB1. Our findings provide support to the theory that SCS emerges from a pre-existing PA while highlighting the multiple genetic changes that could contribute to malignant transformation.

A Case of a Coexisting Carcinosarcoma Ex Pleomorphic Adenoma With Langerhans Cell Histiocytosis in the Parotid Gland

Carcinosarcoma ex pleomorphic adenoma is a rare malignant neoplasm, with most cases reported in the parotid gland. We herein report a case of a 75-year-old male referred to our hospital with a long-standing right parotid lesion that was treated in an outside hospital by a superficial parotidectomy. The patient reported a painful, rapidly enlarging mass following the excision. Histopathological examination showed the proliferation of malignant epithelial and mesenchymal elements with a solid sheet of Langerhans cells admixed with eosinophils. The Langerhans cells were reactive to CD1a and BRAF; hence, a diagnosis of carcinosarcoma ex pleomorphic adenoma with Langerhans cell histiocytosis was given. Complete clinical and radiographic workup showed no other organ involvement. The patient underwent total parotidectomy with adjuvant chemoradiation; however, the tumor progressed and showed lung metastasis. We herein report the first case of a concurrent Langerhans cell histiocytosis with associated carcinosarcoma ex pleomorphic adenoma.

Patterns of Care and Outcomes of Carcinosarcoma of the Major Salivary Glands

OBJECTIVE

Carcinosarcoma of the salivary gland is a rare malignant biphasic tumor. The present study investigates the epidemiology and clinical behavior of carcinosarcoma of the major salivary glands using the National Cancer Database (NCDB).

STUDY DESIGN

Historical cohort study.

SETTING

NCDB.

METHODS

All tumors were selected between 2004 and 2018. Patient demographics, tumor characteristics, treatments, and survival were analyzed. Cox regression analysis was performed in surgically treated patients.

RESULTS

We identified 154 patients in the NCDB with carcinosarcoma of the salivary gland. Median age at diagnosis was 66 years (interquartile range, 55-76). Most patients were male (n = 92, 60%). The majority of tumors were in the parotid (n = 122, 79%), followed by submandibular gland (n = 21, 14%). The majority were high grade (n = 93, 95%), and a significant portion had locally advanced disease (pT3-4; n = 65, 62%). Nodal disease was present in more than one-third (n = 35, 36%). The most common treatment was surgery with adjuvant radiotherapy (n = 75, 49%). With a median follow-up of 36 months, the 3-year overall survival was 57.6% (95% CI, 48.7%-68.0%). In univariable analysis, advanced pT stage, pN+ disease, and positive margins were associated with worse survival. In multivariable analysis, age (hazard ratio, 1.02; 95% CI, 1.01-1.04; P = .03) and pT stage (hazard ratio, 2.51; 95% CI, 1.27-4.95; P = .008) remained significant.

CONCLUSION

Carcinosarcoma is a rare salivary gland tumor that frequently presents at a locally advanced stage. Despite multimodality treatments, the outcomes are poor. In the absence of clinical trial data, these data from the NCDB could guide clinicians in the management of this rare disease.

A case of giant sarcomatoid carcinoma ex-pleomorphic adenoma of the parotid gland

Carcinoma ex pleomorphic adenoma is a rare malignant parotid neoplasm arising from primary or recurrent benign pleomorphic adenoma. Histologically, it can be sub-classified by upwards of eight different variations (e.g., myoepithelial carcinoma, salivary duct carcinoma, adenoid cystic carcinoma sarcomatoid carcinoma). We present the fourth case in the literature of sarcomatoid carcinoma arising from an underlying pleomorphic adenoma of the parotid gland. We present a case of a 47-year-old female who consulted for a left parotid mass of 15cm long axis. There was no facial paralysis. Fine needle aspiration cytology smears showed a pleomorphic adenoma. The parotid MRI showed a left parotid mass, with heterogeneous signal (hyposignal T1 and hypersignal T2 and in diffusion sequences). The patient underwent a total parotidectomy with a pleomorphic adenoma on extemporaneous examination. Histological examination of the part revealed a pleomorphic adenoma on which a sarcomatoid carcinoma developed. Therefore, a second operation occurred. We performed selective lymph node dissection carrying out the sectors I, II and III followed by radiotherapy. The evolution was favorable. In addition to its rarity, our case joins historical cases by its huge size.

High-grade myoepithelial carcinoma can show histologically undifferentiated/anaplastic features

High grade malignant tumors with a poorly-/un-differentiated morphology pose significant diagnostic challenges. Increasingly, the use of adjunct immunohistochemical and molecular tests to characterize and delineate the histopathologic phenotype of these tumors has become necessary, particularly in head and neck tumors. Recently, several entities with a poorly-/un-differentiated light microscopic morphology have been defined based on specific immunohistochemical and genetic characteristics. We herein describe two cases of high-grade myoepithelial carcinoma, one occurring in the submandibular gland and the other occurring in the left nasal cavity, both showing undifferentiated histological and anaplastic cytomorphological features. This led to very broad differential diagnostic considerations and the diagnosis was only established after extensive immunohistochemical studies. Molecular testing for HPV was negative in both cases. Gene fusion analysis using a targeted sequencing assay (Archer® FusionPlex® system) did not identify fusions involving PLAG1, HMGA2, EWSR1 or ALK genes in either case. The submandibular tumor showed an aggressive clinical course, with diffuse pulmonary metastases at presentation, whilst the nasal cavity tumor showed only localized disease. Awareness of a subcategory of high-grade myoepithelial carcinomas with undifferentiated light microscopical features is of significant importance in antibody selection for immunohistochemical investigation of poorly-/undifferentiated malignant tumors in the head and neck region. This histological variant of myoepithelial carcinoma adds to the growing list of differential diagnoses in this diagnostically complex and multifaceted field.

Recurrent Parotid Carcinosarcoma in an Asymptomatic Patient

In this article, we present the case of a 52-year-old male with a history of parotid carcinosarcoma with initial diagnosis being 18 months prior. Initial treatment included a combination of gamma knife surgery coupled with high dosage chemotherapy and X-ray radiation therapy. At the time of follow-up, the patient presented with no complaints and had a nearly normal physical exam with the exception of some facial nerve weakness on the same side as the initial surgery. Despite being asymptomatic, the patient had a significant progression of disease that was manifested with intracranial lesions, multiple pathologic fractures, and a dramatic increase in overall tumor burden. Ultimately, the patient decided to pursue comfort measures only and succumbed to the disease peacefully soon thereafter.