Primary Hepatic Neuroendocrine Tumor and its Metastasis to Breast; Case Report of an Unusual Malignancy

Introduction: Neuroendocrine tumors (NETs) are rare tumors with varied clinical presentations. Entero-pancreatic and respiratory systems are usually involved but it can also affect unusual sites like the liver. Purpose: This paper presents a case of a 45 years female who developed progressive and disabling symptoms of mass effect and carcinoid but remained undiagnosed for many years due to extremely low suspicion of such a tumor in liver. Methods: Diagnosis was made after extensive radiological, histopathological, and biochemical investigations. By that time, disease had spread to her breast which is also not a typical feature of NETs. Findings: Diagnosis of rare tumors at an unusual site is challenging and requires high clinical suspicion and appropriate workup.

Primary hepatic neuroendocrine tumor

Summary Primary hepatic neuroendocrine tumor (PHNET) is a rare type of neuroendocrine tumor (NET) that is also a primary hepatic tumor. Patients are present with almost no specific clinical symptoms and typically present with negative test results and atypical imaging characteristics; therefore, the differentiation of PHNET from other types of primary hepatic masses can be very difficult. In this article, we describe a case of PHNET that mimicked a liver helminth infection in a 57-year-old man. The diagnosis of PHNET in this patient was challenging, and the final diagnosis was based on imaging, histopathology features, and long-term follow-up. Learning points An uncommon type of neuroendocrine tumor (NET) is a primary hepatic neuroendocrine tumor (PHNET). Primary hepatic neuroendocrine tumors are rare NET lesions found in the liver, characterized by non-specific clinical and imaging results, which can be easily confused with other liver lesions, including HCC and parasitic lesions. To have a conclusive diagnosis and classification, a mixture of many medical assessment techniques, such as imaging, gastrointestinal endoscopy, nuclear medicine, anatomy, including histopathology, and immunohistochemistry, is essential.

A Case of Primary Hepatic Neuroendocrine Tumor and Literature Review

We report an unusual presentation of primary hepatic neuroendocrine tumor which was initially misdiagnosed as intrahepatic cholangiocarcinoma. The diagnosis was only revealed after a major liver resection by histopathology. With adjuvant lanreotide injection, the patient survived for more than 16 months after the operation without tumor recurrence. Diagnosis of this rare tumor has been a major challenge and we emphasize the importance of a preoperative diagnosis. Surgical resection remains the mainstay for curative treatment, while peptide receptor radionuclide therapy is an emerging treatment option which has provided promising results.