Intramedullary spinal cord metastases from renal cell carcinomas (RCCs) are rare and can cause serious diagnostic and therapeutic dilemmas. The related reports are very few. This review was aimed to perform an analysis of all reported cases with intramedullary spinal cord metastases from RCCs. In January 2018, we performed a literature search in PubMed database using a combination of the keywords “intramedullary spinal cord metastasis” and “renal cell carcinoma”. In addition, we present the clinical, neuroradiological, and histopathological findings in our patient with an intramedullary metastasis from a RCC. 17 cases were generated in our research. The mean interval from diagnosis of RCC to diagnosis of ISCM was 22 months. The median survival of surgically treated patients was 8.6 months and 8 months in patients who underwent radical surgery. Based on our review, RCCs can invade the medulla of the spinal cord several years after removal of the primary lesion. The prognosis of ISCMs from RCCs was poor. Retrograde passage of tumor cells into the spinal cord from the inferior vena cava via the epidural venous sinuses may have been the pathological mechanism for ISCM in our patient. Radical resection and radiation are effective ways of achieving recovery of neurologic function and improving quality of life. More reports are needed to enable exploration of the mechanisms of metastasis and the optimal forms of therapy.
Intramedullary spinal cord metastases (ISCMs) are rare. They mostly originate from lung and breast cancers but can originate from a wide variety of other solid tumors, including melanoma, malignant lymphoma, and colon, ovarian, and renal cell carcinomas (RCCs) [
In January 2018, we performed a literature search which reported the patient with intramedullary spinal cord metastases from renal cell carcinoma in PubMed database using a combination of the keywords “intramedullary spinal cord metastasis” and “renal cell carcinoma”.
A 58-year-old man presented with numbness and aching pain of both lower extremities without weakness that had been progressive over the previous 2 months and development of paraparesis 3 days before presentation. Physical examination revealed muscle strength of 0/5 below the knee with absence of sensation and 3/5 for the proximal lower limbs. He gave a history of a right RCC with lung metastasis approximately 3 years previously. The renal mass had been discovered by MRI, which had also shown tumor thrombosis in both the renal vein and inferior vena cava (Figures
(a) Abdominal MRI demonstrating right renal cell carcinoma (arrow). (b) MRI also demonstrating tumor thrombosis in the inferior vena cava.
Magnetic resonance imaging (MRI) of the spine demonstrated a 15 mm × 7 mm intramedullary mass at the T12 level with high signals on T2WI, hypointense signals on T1WI, and significant enhancement with intravenous gadolinium (Figures
(a) Preoperative T2-weighted sagittal MRI demonstrating increased signal intensity. (b) Preoperative T1-weighted sagittal MRI revealing a well-defined tumor with significant enhancement after gadolinium injection. (c) Preoperative T1-weighted axial MRI showed well-circumscribed lesion inside the spinal cord at the T12 level.
(a) Photomicrograph demonstrating clear tumor cells. Hematoxylin and eosin, original magnification × 100. Immunohistochemical staining for (b) PAX8, (c) CK(pan), and (d) vimentin showing strong cytoplasmic reactions within tumor cells. Original magnification all × 100.
(a) T1-weighted sagittal MRI after surgery and (b) at a 6-month follow-up showing no evidence of a mass.
The characteristics of reported cases with ISCMs that originated from RCCs, including our patient, are presented in Table
Case reports of ISCM from RCC.
Author | Age/ | Location | RCC location | Diagnosis | Contrast enhancement of MRI | Time from diagnosis of RCC to ISCM (months) | Other RCC metastasis | Treatment | Outcome | Survival after diagnosis of ISCM (months) |
---|---|---|---|---|---|---|---|---|---|---|
Schijns et al. | 70/F | C7 | left | MRI | yes | 0 | liver, contralateral kidney | surgery | improved | >12m |
Poggi et al. | 37/M | T12 | right | MRI, PET | yes | 3 | lung, bone, brain | radiation | unknown | unknown |
Fakih et al. | 56/M | C4 | right | MRI | unknown | 0 | lung, brain | radiation | improved | 6m |
Fakih et al. | 60/M | T2 | right | MRI | unknown | 180 | lung, brain | surgery+radiation | improved | 5m |
Fakih et al. | 68/F | L1 | - | myelography | - | 2 | - | radiation | improved | 16m |
Fakih et al. | 57/F | C7 | - | MRI | yes | 0 | lung, brain | radiation | improved | 5m |
Fakih et al. | 46/M | T5 | right | MRI | yes | 2 | lung, brain | radiation+cis-retinoic+ | improved | 4m |
Fakih et al. | 37/F | C2 | bilateral | MRI | unknown | 25 | lung | surgery | improved | 12m |
Kaya et al. | 43/M | L1 | left | MRI | yes | 12 | systemic organ metastasis | surgery | improved | 6m |
Altinoz et al. | 43/M | T6-7 | bilateral | MRI | unknown | 26 | lung, adrenal gland, brain | surgery | improved | >25m |
Donovan et al. | 41/F | C4 | right | MRI | yes | 0 | multiple bones | surgery | progressed | 6m |
Asadi et al. | 51/F | L1 | left | MRI | no | 0 | brain, multiple bones | - | unknown | unknown |
Parikh et al. | 50/M | C5 | right | MRI | yes | 6 | brain | radiation transformed into stereotactic radiosurgery | improved | >28m |
Zakaria et al. | 62/M | C7 | right | MRI | yes | 1 | lung | surgery | improved | 3m |
Park et al. | 44/M | T12 | left | MRI | yes | 6 | lung | radiation transformed into surgery | improved | >8m |
Gao et al. | 51/M | T4-5 | left | MRI | yes | 72 | - | surgery | improved | >3m |
Present case | 58/M | T12 | right | MRI | yes | 34 | lung | surgery+radiation | improved | >6m |
NE: nephrectomy; CH: chemotherapy; IL-2: interleukin-2; INF: interferon; MT: molecular target; IM: immunotherapy; PS: pulmonary surgery; BS: brain surgery; BR: brain radiation; BOA: bone radiation; AMM: antigen-modulated mini-stem cell transplant.
ISCMs are rare, accounting for 0.1% to 2% of all spinal cord tumors [
Three possible pathological mechanisms have been suggested for how RCCs metastasize to the spinal cord parenchyma [
ISCMs have a poor prognosis. Germ et al. [
RCCs can invade the medulla of the spinal cord several years after removal of the primary lesion. Retrograde passage of tumor cells into the spinal cord from the inferior vena cava via the epidural venous sinuses may have been the pathological mechanism for ISCM in our patient. Radical resection and radiation are effective ways of achieving recovery of neurologic function and improving quality of life. More reports are needed to enable exploration of the mechanisms of metastasis and the optimal forms of therapy.
The authors have no conflicts of interest to declare.
This study was supported by grants from the National Natural Science Foundation of China (no. 81501065), Zhejiang Provincial Natural Science Foundation (no. LY16H090004), and International Cooperation Project of Science Technology Department of Zhejiang Province (no. 2015C34007). We thank Dr. Trish Reynolds, MBBS, FRACP, from Liwen Bianji, Edanz Group China (