Skeletal metastasis of carcinoid tumors: Two case reports and review of the literature

Abstract

Abstract. Carcinoid tumors are neuroendocrine neoplasms derived from enterochromaffin cells. Skeletal metastases from carcinoid tumors are considered to be extremely rare. In this study, we present two cases of carcinoid tumors that metastasized to the bone. Furthermore, we review 50 published case reports and reveal the features of skeletal metastasis of carcinoid tumors. The first case involved a 59-year-old man with a history of multiple metastases of a lung carcinoid tumor. The patient complained of back pain and numbness in the lower limbs. Magnetic resonance imaging revealed metastases in the thoracic spine. A spinal decompression was performed and the symptoms were resolved. The second case involved a 74-year-old man had been diagnosed with a lung carcinoid tumor 15 years previously and complained of left thigh pain. A radiograph showed osteolytic lesions in the shaft of the left femur. We repaired the femur using an intramedullary nail following curettage of the tumor. A radiograph of the femur revealed a callus on the pathological fracture. The patient was able to walk using a crutch 3 months after surgery. We reviewed 50 cases that described skeletal metastasis from carcinoid tumors. The average age of the patients was 54.9 years and 33 patients (66%) were male. The most common site of skeletal metastasis was the spine. We also investigated the survival rate of patients who developed skeletal metastasis from carcinoid tumors. The findings showed that survival of patients who developed osteolytic skeletal metastasis was worse than that of patients who developed osteosclerotic skeletal metastasis.

C8-T1 Radiculopathy Due to an Intradural Extramedullary Metastasis of a Pancreatic Neuroendocrine Tumor

“…Carcinoid tumors were of bronchial (n = 9) and nonpulmonary origin (n = 17)-of which CNS (n = 2) and thymus (n = 3)-, and 4 patients had carcinoid tumors of unknown primary, whereas in 7 patients, the origin was not specified. [16][17][18][19][20][21][22][23][24][26][27][28][29][30][31][32]34,35,37,38,43 Only 6 pNET cases, including ours, of malignant spinal cord compression have been reported in the literature, 25,33,36,40,41 with two of them due to "functional" pNETs (ie, glucagonoma, gastrinoma). As far as we know, our case is the first ever reported of a pNETwith an "intradural" metastasis to the spinal cord, and we only found the following 4 other cases of spinal intradural NET metastases: 2 thymic carcinoids, 28,35 1 lung atypical carcinoid, 18 and a probable primary atypical carcinoid of the CNS.…”

“…42 Most of the cases (n = 35) are in fact extradural spinal cord compressions due to vertebral metastases with an epidural soft tissue component. 16,19,[21][22][23][24][25][26]29,[32][33][34][35][36][37][38][39]41,43 Reported cases include carcinoid tumors (n = 36), pNET (n = 6), and NETs of unknown primary (n = 3). Carcinoid tumors were of bronchial (n = 9) and nonpulmonary origin (n = 17)-of which CNS (n = 2) and thymus (n = 3)-, and 4 patients had carcinoid tumors of unknown primary, whereas in 7 patients, the origin was not specified.…”

Reviewing the Osteotropism in Neuroendocrine Tumors: The Role of Epithelial-Mesenchymal Transition

“…Although skeletal involvement in carcinoid patients is rarely considered symptomatic [43,44], we found that bone pain and/or neurologic symptoms related to spinal cord or nerve root compression were present in 55 and 22% of the overall cohort, respectively. Of note, SREs occurred in 24% of the patients and were diagnosed at borderline increased frequency in patients with metachronous bone metastases (p = 0.08), probably as a consequence of their delayed detection.…”

“…However, bone metastases have been historically regarded as rare complications of NETs and their clinical relevance has been frequently confined to symptomatic patients [43]. Therefore, whether or not skeletal metastases should be systematically investigated in patients with NETs, who might be at increased risk of morbidity from bone metastases, whether markers of malignant osteoclastogenesis are useful in clinical practice, and what is the management of bone-metastatic NETs are still unknown topics since international guidelines do not suggest evidence-based recommendations in this regard [4,44].…”

Hepatic Resection for Metastatic Neuroendocrine Cancer in Patients with Bone Metastases

“…Previous reports show that patients with skeletal metastases from carcinoid tumors do not always complain of pain. 14,15 Similarly, only 44 % of patients herein underwent localized therapy of their symptomatic bone metastases. Most patients in our study were treated with radiotherapy (40 %).…”