RESUMO
Epithelioid hemangioendothelioma (EHE) is a rare low-grade malignant vascular tumor. It mainly occurs in the liver, lungs, bones, and other parts of the body. Reports of epithelioid hemangioendothelioma in the parotid gland are rare in both domestic and international literature. Here, we present a case report of a parotid gland epithelioid hemangioendothelioma, including its complete clinical course and imaging findings, to improve the diagnosis and treatment of this unusual disease. Case presentation: The patient, a 75-year-old female, presented with a swelling around the right ear for 2 months and pain for 20 days. Enhanced MRI of the parotid gland revealed a well-defined, round mass with homogeneous signal intensity. The mass showed low signal intensity on T1-weighted imaging, high signal intensity on T2-weighted imaging, nodular low signal intensity within, significant high signal intensity on DWI sequence, low signal intensity on ADC sequence, and heterogeneous enhancement in the arterial phase after intravenous injection of Gd-DTPA. Nodular non-enhancing low signal intensity was observed internally, and slight clearance was seen in the venous phase. The initial diagnosis before surgery was a benign lesion, but after histopathological and immunohistochemical examination, it was confirmed as epithelioid hemangioendothelioma. Intervention: Complete tumor resection was performed. Results: The patient experienced a favorable recovery, with meticulous follow-up conducted for up to 1 year revealing no signs of recurrence or metastasis. Continued patient surveillance is ongoing to substantiate and validate the long-term efficacy of the treatment. Conclusion: Due to the extreme rarity of parotid gland epithelioid hemangioendothelioma, it often leads to a high misdiagnosis rate. The most common misdiagnosis is salivary gland lymphoma, followed by epithelioid hemangiosarcoma. When the lesion is multifocal, fusiform, with internal necrosis, and shows punctate low signal intensity on T2-weighted imaging, significant enhancement in the arterial phase, particularly with more pronounced peripheral enhancement, and persistent enhancement in the venous and delayed phases, epithelioid hemangioendothelioma should be considered. However, the current clinical diagnosis of epithelioid hemangioendothelioma still primarily relies on immunohistochemical methods.
RESUMO
BACKGROUND: Malignant proliferating trichilemmal tumor (MPTT) is an infrequent malignant neoplasm originating from cutaneous appendages, with only a handful of documented cases. This report delineates a unique instance of MPTT situated in the neck, accompanied by lymph node metastasis. A comprehensive exposition of its clinical trajectory and imaging manifestation is presented, aiming to enhance comprehension and management of this atypical ailment. CASE SUMMARY: Patient concerns: A 79-year-old male presented with a longstanding right neck mass persisting for over six decades, exhibiting recent enlargement over the past year. Diagnoses: Enhanced magnetic resonance imaging of the neck unveiled an elliptical mass on the right neck side, characterized by an ill-defined border and a heterogeneous signal pattern. The mass exhibited subdued signal intensity on T1-weighted imaging (T1WI) and a heterogeneous high signal on T2-weighted imaging (T2WI), interspersed with a lengthy T1 and T2 cystic signal motif. Close anatomical association with the submandibular gland joint was noted, and intravenous gadolinium diethylene triamine pentaacetic acid administration facilitated conspicuous enhancement. Substantial enhancement of the solid segment prompted an initial preoperative diagnosis of malignant nerve sheath tumor. However, post-surgery histopathological and immunohistochemical analysis conclusively confirmed the diagnosis as malignant hyperplastic external hair root sheath tumor. Intervention: Complete excision of the tumor was successfully executed. Outcomes: The patient experienced a favorable postoperative recovery. CONCLUSION: Malignant proliferative trichilemmal tumor external hair root sheath tumor is a cystic-solid lesion, appearing as low signal on T1WI images or high signal on T2WI with enhancement of the solid component. Suspicions of malignancy are heightened when the tumor border is indistinct, tissue planes are breached, or when linear or patchy high signals are observed in the subcutaneous tissue on T1 liver acquisition with volume acceleration enhanced images along with intermediate signal on T2WI and restricted diffusion on diffusion-weighted imaging images. Strong consideration for malignancy should arise if there are signs of compromised adjacent tissue relationships or direct invasion evident on imaging. We have incorporated the above-mentioned content into the entire manuscript.