Patients’ characteristics
As shown in Table 1, 44 patients (24 men and 20 women) were identified who met the selection criteria. The median age was 62.5 years (range, 39-88 years). Twenty-six patients (59%) were white, and 16 patients (36%) were black. Nineteen patients (43%) had breast cancer, 18 patients (41%) had prostate cancer, and 6 patients (14%) had multiple myeloma. Additional cancer types included thyroid cancer, tongue squamous cell carcinoma, olfactory neuroblastoma, lung carcinoma, B-cell lymphoblastic leukemia, and diffuse large B-cell lymphoma, and were diagnosed in one patient (2% each; not shown).
Diagnostic procedures
Imaging procedures were performed before and during diagnosis of clival metastasis, including magnetic resonance imaging (MRI) of the brain in 41 patients (93%), abdominal and thoracic computed tomography (CT) scans in 34 patients (77%), pelvic CT in 33 patients (75%), and whole body bone scan in 32 patients (73%; Table 1). Of note, 32 of all 44 patients (73%) diagnosed with clival metastases were also diagnosed with cervical spine metastases. Bone marrow biopsy of the pelvis was done in 7 of 44 patients (16%) as part of their clinical care, irrespective of clival metastasis diagnosis.
RT treatment
Twenty-three patients of 44 patients (52%) were treated with RT. Median time from diagnosis of clival metastasis to the start of RT was 9 days (range, 0-405 days). Sixteen patients of 23 RT-treated patients (70%) had cervical spine metastasis. The time from the diagnosis of cervical spine metastasis to completion of RT treatment ranged from 7 to 419 days, with the median time of 23 days. As depicted in Table 1, 16 of 24 men (70%) received RT, whereas only 7 of 20 women (30%) did. The median age of RT-treated patients was 63 years (range, 41-88 years). Fourteen patients of 23 RT-treated patients (61%) were whites, and 8 patients (35%) were African Americans. Among 23 RT-treated patients, 6 patients (26%) were with breast cancer, 10 patients (43%) were with prostate cancer, and 4 patients (17%) were with multiple myeloma. Twenty patients of 23 RT-treated patients (87%) received MRI of the brain, 15 patients (65%) got either abdominal CT or thoracic CT scan, or whole body bone scan, and 14 patients (61%) received pelvic CT. Bone marrow biopsy of the pelvis was done in five patients of 23 RT-treated patients (22%; not shown).
Fifteen patients of 23 RT-treated patients (65%) received clivus only RT, and 8 patients (35%) had whole brain RT. Of all 15 patients who were treated with clivus only RT, 2 patients (13.3%) also received RT to the cervical spine (not shown). Among clivus only RT-treated patients, 12 patients received 30 Grays (Gy; in 3 Gy x 10 fractions), one patient had a total 20 Gy treatment (in 4 Gy x 5 fractions), and one patient was given an 8 Gy x 1 treatment only. One patient, previously treated in the base of skull region, received a lower dose of 2.5 Gy x 10 fractions using intensity-modulated RT to minimize overlap with the previous treatment. Among whole brain RT-treated patients, 6 patients were given 30 Gy in 10 fractions, one patient received 25 Gy in 10 fractions, and one patient was treated with a total of 12 Gy (3 Gy x 4) out of 30 Gy (3 Gy x 10) planned treatment prior to discontinuing due to worsening of the performance status.
Of all 44 patients in the study, 7 patients (15.9%) expired within 3 months after the diagnosis of clival metastasis, and ended up receiving no RT treatment (Table 2). Among them, 5 patients (11.4%) were with prostate cancer, one patient (2.3%) was with breast cancer, and one patient (2.3%) was diagnosed with both breast cancer and multiple myeloma. Of note, 14 patients (31.8%), who received care outside our institution, were with unknown RT status. Among them, 2 patients (4.5%) were with prostate cancer, 11 patients (25.0%) were diagnosed with breast cancer, and one patient (2.3%) was with both prostate cancer and multiple myeloma.
Types of neurologic symptoms
Common neurologic symptoms noted in all 44 patients are depicted in Table 3. Thirteen patients (30%) suffered from headache, 7 patients (16%) experienced diplopia, 6 patients (14%) had lateral gaze paralysis, 5 patients (11%) presented with blurry vision or chin numbness, and 4 patients (9%) suffered from tongue deviation. Some patients experienced more than one symptom.
Table 3 also shows neurologic symptoms based on cancer type. Patients with breast cancer experienced headache (6/13; 46%), and blurry vision or chin numbness (1/5; 20% each). Patients with prostate cancer had diplopia (4/7; 57%), tongue deviation (2/4; 50%), blurry vision or chin numbness (2/5; 40% each), lateral gaze deficit (2/6; 33%), and headache (3/13; 23%). The symptoms noted in patients with multiple myeloma were tongue deviation (2/4; 50%), lateral gaze deficit (2/6; 33%), diplopia (2/7; 29%), and headache (3/13; 23%), in addition to blurry vision or chin numbness (1/5; 20% each).
Symptom improvement after RT
Symptom improvement after RT was defined as lessening or resolution of a symptom based on patients’ reports. As shown in Table 4, symptom improvement after RT was experienced by 5 of 6 patients (83%) with diplopia, 8 of 10 patients (80%) with headache, 2 of 4 patients (50%) with chin numbness, 2 of 5 patients (40%) with blurry vision, 2 of 6 patients (33%) with lateral gaze deficit, and one of 4 patients (25%) with tongue deviation.
A classic example of the patients in this study is a 58-year old patient with metastatic castrate-resistant prostate cancer, who initially presented with severe headaches. The clival involvement was noted using the MRI scan (Fig. 1a). In this case, the RT treatment plan was 3000 centigrays (cGy) delivery in 10 fractions using opposed laterals and 6 megavolts (MV) photons. The total dose of 3000 cGy was delivered to the entire gross tumor volume, and to 95% of the planning target volume (Fig. 1b). The RT treatment resulted in significant improvement of headaches.