Up-front single-session radiosurgery for large brain metastases-volumetric responses and outcomes

BACKGROUND

Patients presenting with large brain metastases (LBM) pose a management challenge to the multidisciplinary neuro-oncologic team. Treatment options include surgery, whole-brain or large-field radiation therapy (WBRT), stereotactic radiosurgery (SRS), or a combination of these.

OBJECTIVE

To determine if corticosteroid therapy followed by SRS allows for efficient minimally invasive care in patients with LBMs not compromised by mass effect.

METHODS

We analyzed the change in tumor volume to determine the efficacy of single-session SRS in the treatment of LBM in comparison to other treatment modalities. Twenty-nine patients with systemic cancer and brain metastasis (≥ 2.7 cm in greatest diameter) who underwent single-session SRS were included.

RESULTS

Among 29 patients, 69% of patients had either lung, melanoma, or breast cancer. The median initial tumor size (maximal diameter) was 32 mm (range 28-43), and the median initial tumor volume was 9.56 cm³ (range 1.56-25.31). The median margin dose was 16 Gy (range 12-18). The average percent decrease in tumor volume compared to pre-SRS volume was 55% on imaging at 1-2 months, 58% at 3-5 months, 64% at 6-8 months, and 57% at > 8 months. There were no adverse events immediately following SRS. Median corticosteroid use after SRS was 21 days. Median survival after radiosurgery was 15 months.

CONCLUSION

Initial high-dose corticosteroid therapy followed by prompt single-stage SRS is a safe and efficacious method to manage patients with LBMs (defined as ≥ 2.7 cm).

Evaluation of the ability of the Brainlab Elements Cranial Distortion Correction algorithm to correct clinically relevant MRI distortions for cranial SRT

PURPOSE

Cranial stereotactic radiotherapy (SRT) requires highly accurate lesion delineation. However, MRI can have significant inherent geometric distortions. We investigated how well the Elements Cranial Distortion Correction algorithm of Brainlab (Munich, Germany) corrects the distortions in MR image-sets of a phantom and patients.

METHODS

A non-distorted reference computed tomography image-set of a CIRS Model 603-GS (CIRS, Norfolk, VA, USA) phantom was acquired. Three-dimensional T1-weighted images were acquired with five MRI scanners and reconstructed with vendor-derived distortion correction. Some were reconstructed without correction to generate heavily distorted image-sets. All MR image-sets were corrected with the Brainlab algorithm relative to the computed tomography acquisition. CIRS Distortion Check software measured the distortion in each image-set. For all uncorrected and corrected image-sets, the control points that exceeded the 0.5-mm clinically relevant distortion threshold and the distortion maximum, mean, and standard deviation were recorded. Empirical cumulative distribution functions (eCDF) were plotted. Intraclass correlation coefficient (ICC) was calculated. The algorithm was evaluated with 10 brain metastases using Dice similarity coefficients (DSC).

RESULTS

The algorithm significantly reduced mean and standard deviation distortion in all image-sets. It reduced the maximum distortion in the heavily distorted image-sets from 2.072 to 1.059 mm and the control points with > 0.5-mm distortion fell from 50.2% to 4.0%. Before and especially after correction, the eCDFs of the four repeats were visually similar. ICC was 0.812 (excellent-good agreement). The algorithm increased the DSCs for all patients and image-sets.

CONCLUSION

The Brainlab algorithm significantly and reproducibly ameliorated MRI distortion, even with heavily distorted images. Thus, it increases the accuracy of cranial SRT lesion delineation. After further testing, this tool may be suitable for SRT of small lesions.

Resecting the dominant lesion: Patient outcomes after surgery and radiosurgery vs stand-alone radiosurgery in the setting of multiple brain metastases

BACKGROUND

Brain metastases are the most common central nervous system (CNS) tumors, occurring in 300,000 people per year in the US. While there are immediate local benefits to surgical resection for dominant lesions, including reduction of tumor burden and edema, the survival benefits of surgical resection, over radiosurgery, remains unclear.

METHODS

The University of Pennsylvania Health System database was retrospectively reviewed for patients presenting with multiple brain metastases from 1/1/16-8/31/18 with one dominant lesion > 2 cm in diameter, who underwent initial treatment with either resection of the dominant lesion or Gamma Knife radiosurgery (GKS). Inclusion criteria were age > 18, > 1 brain metastasis, and presence of a dominant lesion (>2 cm). We analyzed factors associated with mortality.

RESULTS

129 patients were identified (surgery=84, GKS=45). The median number of intracranial metastases was 3 (IQR: 2-5). The median diameter of the largest lesion was 31 mm (IQR: 25-38) in the surgery group vs 21 mm (IQR: 20-24) in the GKS group (p < 0.001). Mortality did not differ between surgery and GKS patients (69.1% vs 77.8%, p = 0.292). In a multivariate survival analysis, there was no difference in mortality between the surgery and GKS cohorts (aHR: 1.35, 95% CI: 0.74-2.45 p = 0.32). Pre-operative KPS (aHR: 0.97, 95% CI: 0.95-0.99, p = 0.004), CNS radiotherapy (aHR: 0.33, 95% CI: 0.19-0.56 p < 0.001), chemotherapy (aHR: 0.27, 95% CI: 0.15-0.47, p < 0.001), and immunotherapy (aHR: 0.41, 95% CI: 0.25-0.68, p = 0.001) were associated with decreased mortality.

CONCLUSION

In our institution, patients with multiple brain metastases and one symptomatic dominant lesion demonstrated similar survival after GKS when compared with up-front surgical resection of the dominant lesion.

Possible Overcoming of Tumor Hypoxia with Adaptive Hypofractionated Radiosurgery of Large Brain Metastases: A Biological Modeling Study

OBJECTIVE

The present biological modeling study evaluated possible application of adaptive hypofractionated stereotactic radiosurgery (HSRS), which involves escalation of the prescription dose according to the gradual decrease in the tumor volume between treatment sessions separated by 2- to 3-week intervals, in the management of large brain metastases.

METHODS

To investigate the effects of dose escalation during three-stage adaptive HSRS, a generalized biologically effective dose (gBED) model was applied. Accounting for both a nonuniform dose distribution inside the target and tumor hypoxia was implemented, and normal brain radiation dose distributions were assessed.

RESULTS

In comparison with conventional three-stage HSRS (with an identical prescription dose of 10 Gy at each treatment session), adaptive HSRS resulted in a 30-40% increase in gBED. This effect was especially prominent in late-responding targets (with α/β ratios from 3 to 10 Gy) and in neoplasms containing a high percentage of hypoxic cells. Despite dose escalation in the target, irradiation of the adjacent normal brain tissue was kept within safe limits at a level similar to that applied in conventional three-stage HSRS.

CONCLUSION

Adaptive HSRS theoretically results in significant enhancement of gBED in the target and may possibly overcome resistance to irradiation, which is caused by tumor hypoxia. These advantages may translate into higher treatment efficacy in cases of large brain metastases.

Redistributing Central Target Dose Hot Spots for Hypofractionated Radiosurgery of Large Brain Tumors: A Proof-of-Principle Study

OBJECTIVE

The present proof-of-principle study investigated radiobiological effects of redistributing central target dose hot spots across different treatment fractions during hypofractionated stereotactic radiosurgery (HSRS) of large intracranial tumors.

METHODS

Redistribution of central target dose hot spots during HSRS was simulated, and its effects were evaluated in eight cases of brain metastases. To assess dose variations in the target across N number of treatment fractions, a generalized biologically effective dose (gBED) was formulated. The gBED enhancement ratio was defined as the ratio of gBED in the tested treatment plan (with central target dose hot spot redistributions across fractions) to gBED in the conventional treatment plan (without central target dose hot spot redistributions).

RESULTS

At a median α value of 0.3/Gy, the tested treatment plans resulted in average gBED increases of 15.6 ± 3.5% and 8.3 ± 1.8% for α/β ratios of 2 and 10 Gy, respectively. In comparison with conventional treatment plans, the differences in the Paddick conformity index and gradient index did not exceed 2%.

CONCLUSION

Redistributing central target dose hot spots across different treatment fractions during HSRS may be considered promising for enhancing gBED in the target. It may be beneficial for management of large intracranial neoplasms; thus, it warrants further clinical testing.

Predicting response to radiotherapy of intracranial metastases with hyperpolarized [Formula: see text]C MRI

BACKGROUND

Stereotactic radiosurgery (SRS) is used to manage intracranial metastases in a significant fraction of patients. Local progression after SRS can often only be detected with increased volume of enhancement on serial MRI scans which may lag true progression by weeks or months.

METHODS

Patients with intracranial metastases (N = 11) were scanned using hyperpolarized [Formula: see text]C MRI prior to treatment with stereotactic radiosurgery (SRS). The status of each lesion was then recorded at six months post-treatment follow-up (or at the time of death).

RESULTS

The positive predictive value of [Formula: see text]C-lactate signal, measured pre-treatment, for prediction of progression of intracranial metastases at six months post-treatment with SRS was 0.8 [Formula: see text], and the AUC from an ROC analysis was 0.77 [Formula: see text]. The distribution of [Formula: see text]C-lactate z-scores was different for intracranial metastases from different primary cancer types (F = 2.46, [Formula: see text]).

CONCLUSIONS

Hyperpolarized [Formula: see text]C imaging has potential as a method for improving outcomes for patients with intracranial metastases, by identifying patients at high risk of treatment failure with SRS and considering other therapeutic options such as surgery.

Cumulative Intracranial Tumor Volume as a Prognostic Factor in Patients with Brain Metastases Undergoing Stereotactic Radiosurgery

Approximately 25-35% of all cancer patients suffer from brain metastases (BM), and many of them-in particular, those with a limited number of intracranial tumors-are treated with stereotactic radiosurgery (SRS). Accurate prediction of survival remains a key clinical challenge in this population. Several prognostic scales have been developed to facilitate this prognostication, including the Recursive Partitioning Analysis (RPA) classification, the modified Recursive Partitioning Analysis (mRPA) subclassifications, the Basic Score for Brain Metastases (BS-BM), the Score Index for Radiosurgery (SIR), the Graded Prognostic Assessment (GPA), and the diagnosis-specific Graded Prognostic Assessment (dsGPA). However, none of these scales include consideration of the cumulative intracranial tumor volume (CITV), which is defined as the sum of all intracranial tumor volumes. Since there is mounting evidence that the CITV carries significant prognostic value in SRS-treated patients with BM, this variable should be considered during survival prognostication, along with other pertinent clinical, pathological, and molecular characteristics.

Stereotactic Radiosurgery to Prevent Local Recurrence of Brain Metastasis After Surgery: Neoadjuvant Versus Adjuvant

Over the past 15-20 years, stereotactic radiosurgery (SRS) has become the dominant method for treating patients with brain metastases (BM). The role of surgery for management of large tumors also remains important. Combining these two treatment modalities may well achieve the best local control, safety, and symptomatic relief in cases of neoplasms for which resection is desirable. After 10 years of retrospective studies that suggested patients might do better if surgery were followed by early adjuvant SRS, a prospective, randomized, controlled trial was conducted to compare such treatment with postoperative observation after tumor removal, and it showed significantly better local control in the former cohort, especially in smaller lesions, but no difference in overall survival. On the other hand, in the past 5 years, some groups have argued that neoadjuvant SRS before resection of BM might be superior to adjuvant SRS, while no clinical trial has yet been concluded that compares these two treatment strategies. For now, adjuvant and neoadjuvant SRS show evidence of utility in achieving better local control after surgical removal of BM in comparison with surgery alone, but no specific guidelines exist favoring one method over the other, and both should be considered beneficial in clinical care.

Evidence-Based Recommendations for Seizure Prophylaxis in Patients with Brain Metastases Undergoing Stereotactic Radiosurgery

Symptomatic epilepsy is frequently encountered in patients with brain metastases (BM), affecting up to 25% of them. However, it generally remains unknown whether the risk of seizures in such cases is affected by stereotactic radiosurgery (SRS), which involves highly conformal delivery of high-dose irradiation to the tumor with a minimal effect on adjacent brain tissue. Thus, the role of prophylactic administration of antiepileptic drugs (AED) after SRS remains controversial. A comprehensive review and analysis of the available literature reveals that according to prospective studies, the incidence of seizures after SRS for BM varies from 8% to 22%, and there is no evidence that SRS increases the incidence of symptomatic epilepsy. Therefore, routine prophylactic administration of AED prior to, during, or after SRS in the absence of a seizure history is not recommended. Nevertheless, short-course administration of an AED may be judiciously considered (on the basis of class III evidence) for selected high-risk individuals.

Dacomitinib induces objective responses in metastatic brain lesions of patients with EGFR-mutant non-small-cell lung cancer: A brief report

OBJECTIVE

Dacomitinib is a potent, irreversible and pan-HER tyrosine kinase inhibitor (TKI) of epidermal growth factor receptor (EGFR) mutant non-small cell lung cancer (NSCLC). Currently, evidence of its activity on brain metastasis is lacking.

MATERIALS AND METHODS

NSCLC patients diagnosed at Hunan Cancer Hospital between July, 2019 and July, 2020 with enhanced MRI-detected brain metastasis prior to treatment and laboratory-confirmed EGFR mutations were reviewed. In total, 14 EGFR-mutant NSCLC patients with brain metastasis were treated with first-line dacomitinib. The first radiographic review of chest CT and brain MRI was after one month and thereafter every 2 months. The objective response rate (ORR) and the depth of the brain metastasis response were determined via RECIST 1.1 and RANO-LM criteria.

RESULTS

In total, 14 of 59 EGFR-mutant advanced NSCLC patients who received first-line dacomitinib therapy had brain metastasis before treatment. Among these patients, 5 were given a dacomitinib starting dose of 45 mg once daily, while 9 received 30 mg daily until disease progression or unbearable toxicity. Eight patients harbored EGFR 19del, 5 had EGFR L858R, and one patient had EGFR G719A and I706 T co-mutations. The median duration of follow-up was 4.5 months. All patients received at least one review. The ORR was 92.9 % (13/14) and the disease control rate (DCR) was 100 %. A measurable response of the intracranial metastases was observed in 12 of 14 patients (85.7 %), including 12 of 13 (92.3 %) with brain parenchymal metastasis, but the one patient with meningeal metastasis did not respond well. All patients (100 %) had grade 1-2 adverse effects, but none discontinued treatment or required a dosage adjustment.

CONCLUSIONS

This case series study of 14 patients has shown that dacomitinib has potent efficacy for central nervous system (CNS) metastasis in EGFR-positive NSCLC. More data are required to confirm its advantages and optimize its clinical application.

Combined Immunotherapy and Stereotactic Radiotherapy Improves Neurologic Outcomes in Patients with Non-small-cell Lung Cancer Brain Metastases

BACKGROUND

The purpose of this study was to compare the outcomes of patients with non-small cell lung cancer (NSCLC) brain metastases treated with stereotactic radiotherapy (SRT) alone versus SRT and immune checkpoint inhibitors (ICIs).

PATIENTS AND METHODS

Patients treated for their first diagnosis of intracranial metastases with SRT or SRT plus ICI were retrospectively identified. Overall survival (OS), local control (LC), distant brain failure (DBF), neurologic death, and rates of radiation necrosis were calculated. Univariate (UVA) and multivariable (MVA) analyses with competing risk analysis were performed.

RESULTS

Seventy-seven patients with 132 lesions were analyzed, including 44 patients with 68 lesions in the SRT group and 33 patients with 64 lesions in the SRT plus ICI group. There were no differences in baseline factors between groups. Use of ICI predicted for decreased DBF (hazard ratio [HR], 0.45; 95% confidence interval [CI], 0.24-0.84; P = .01), decreased rates of neurologic death (HR, 0.29; 95% CI, 0.10-0.85; P = .02), and better OS (HR, 0.46; 95% CI, 0.23-0.91; P = .03). Two-year LC was 97% for the SRT + ICI group, and 86% for the SRT-alone group (P = .046). Actuarial 2-year DBF was 39% for the SRT + ICI group and 66% for the SRT alone group (P = .016). On MVA, ICI use persisted in predicting lower incidence of neurologic death (HR, 0.25; 95% CI, 0.09-0.72; P = .01) and DBF (HR, 0.47; 95% CI, 0.25-0.85; P = .01) when adjusted for competing risk of death.

CONCLUSION

In this cohort of patients with NSCLC brain metastases, ICI use combined with SRT predicted for improved LC and OS and decreased DBF and risk of neurologic death.

The value of structured radiology reports to categorize intracranial metastases following radiation therapy

PURPOSE

Radiology descriptions of intracranial metastases following radiotherapy are often imprecise. This study sought to improve such reports by creating and disseminating a structured template that encourages discrete categorization of intracranial lesions.

METHODS

Following initiation of the structured template, a retrospective review assessed patients with intracranial metastases that underwent radiotherapy, comparing 'pre-template' with 'post-template' reports. A total of 139 patients were included; 94 patients (67.6%) were imaged pre-template, 45 (32.4%) post-template. Reports were assessed for discrete versus non-specific descriptions of lesions: '(presumed) new metastases', 'treated metastases', and 'indeterminate lesions'. Non-specific language was subdivided based on the type of lesion(s) described: e.g. 'stable enhancing foci' was deemed a non-specific description of 'treated metastases'.

RESULTS

Non-specific descriptions of lesions were used in 25/94 reports (26.6%) pre-template, and eight reports (17.8%) post-template. No significant difference was found in the frequency of inappropriate/ambiguous descriptions of intracranial lesions following template initiation (P = 0.52). However, only 27/45 (60.0%) of the reports in the post-template time period used the structured report; the other reports were written as free prose. Of the reports that did use the structured template, the authors used significantly less ambiguous language structured template (P = 0.02).

CONCLUSION

When utilized, a structured report template resulted in decreased non-specific descriptions and improved discrete characterization of intracranial metastases in patients treated with radiation. However, the frequency of non-specific language usage before and after template initiation was unchanged, probably due to poor compliance with template utilization.

Milestones in stereotactic radiosurgery for the central nervous system

INTRODUCTION

Since Lars Leksell developed the first stereotactic radiosurgery (SRS) device in 1951, there has been growth in the technologies available and clinical indications for SRS. This expansion has been reflected in the medical literature, which is built upon key articles and institutions that have significantly impacted SRS applications. Our aim was to identify these prominent works and provide an educational tool for training and further inquiry.

METHOD

A list of search phrases relating to central nervous system applications of stereotactic radiosurgery was compiled. A topic search was performed using PubMed and Scopus databases. The journal, year of publication, authors, treatment technology, clinical subject, study design and level of evidence for each article were documented. Influence was proposed by citation count and rate.

RESULTS

Our search identified a total of 10,211 articles with the top 10 publications overall on the study of SRS spanning 443-1313 total citations. Four articles reported on randomized controlled trials, all of which evaluated intracranial metastases. The most prominent subtopics included SRS for arteriovenous malformation, glioblastoma, and acoustic neuroma. Greatest representation by treatment modality included Gamma Knife, LINAC, and TomoTherapy.

CONCLUSIONS

This systematic reporting of the influential literature on SRS for intracranial and spinal pathologies underscores the technology's rapid and wide reaching clinical applications. Moreover the findings provide an academic guide to future health practitioners and engineers in their study of SRS for neurosurgery.

Unmasking of intracranial metastatic melanoma during ipilimumab/nivolumab therapy: case report and literature review

BACKGROUND

While data from several studies over the last decade has demonstrated that introduction of immunologic checkpoint blockage therapy with anti-CTLA-4/PD-1 drugs leads to improved survival in metastatic melanoma patients, relatively little is known about brain-specific therapeutic response and adverse events in the context of immunotherapeutic treatment of intracranial disease. Here we report two independent cases of new intracranial metastases presenting after initiation of combined checkpoint blockade Ipilimumab and Nivolumab for recurrent metastatic melanoma in the context of positive systemic disease response.

CASE PRESENTATION

Case #1: A 43-year-old Caucasian male with Stage III melanoma of the left knee had subsequent nodal, hepatic and osseous metastases and was started on ipilimumab/nivolumab. He developed an intractable headache one week later. MRI revealed new enhancing and hemorrhagic brain metastases. After 6 weeks of immunotherapy, there was interval hemorrhage of a dominant intracranial lesion but substantial improvement in systemic metastatic disease. Durable, near complete intracranial and systemic response was achieved after completion of both induction and maintenance immunotherapy. Case #2: A 58-year old Caucasian woman with stage II melanoma of the right index finger developed cutaneous, pulmonary and hepatic metastases within 4 months of adjuvant radiation. Although combined checkpoint blockade resulted in improvement in both cutaneous and systemic disease, brain MR performed for eye discomfort demonstrated new enhancing and hemorrhagic brain metastases. Serial MR imaging five months later revealed only a solitary focus of brain enhancement with continued improved systemic disease.

CONCLUSIONS

These cases raise the question of whether the initial immune activation and modulation of the blood brain barrier by Ipilimumab/Nivolumab somehow "unmasks" previously clinically silent metastatic disease, rather than representing new or progressive metastatic disease. An overview of currently available literature discussing the role of immune checkpoint blockade in the treatment of intracranial metastatic melanoma will be provided, as well as discussion highlighting the need for future work elucidating the response of brain metastases to anti-CTLA/PD-1 drugs and documentation of brain-specific adverse events.

Management of Solitary Intracranial Metastases of Differentiated Thyroid Carcinoma: 11 Pathologically Confirmed Cases and Systematic Literature Review

BACKGROUND

Solitary intracranial metastases of differentiated thyroid carcinoma (DTC) are rare, and their management is still controversial. This research aimed to seek suitable therapeutic methods for this disease.

METHODS

We retrospectively studied 11 pathologically confirmed cases of solitary intracranial metastases of DTC in a single institution from January 2000 to December 2016 and systematically reviewed 52 cases of this disease out of 416 cases described in the literature on PubMed. These 63 cases were analyzed by Kaplan-Meier analysis, Cox regression analysis, and post-hoc test.

RESULTS

The diameters of intracranial metastases in all 63 cases were greater than 2 cm. Lung metastases (P = 0.000) and neurosurgery (P = 0.014) were 2 independent prognostic factors of this disease. Only neurosurgery (P = 0.05) was an independent prognostic factor in the patients with lung metastases, and neurosurgery (P = 0.044) and whole brain radiotherapy (WBRT) (P = 0.041) were 2 independent factors in the patients without lung metastases. Longer overall survival (OS) was achieved in the gross total removal (GTR) and subtotal removal (STR) groups than in the no neurosurgery group (P = 0.015, P = 0.084, respectively), and there was no significance between the GTR and STR groups (P = 0.918).

CONCLUSION

The patients without lung metastases had a better prognosis than did the patients with lung metastases. Neurosurgery could obviously improve the prognosis, and if possible, GTR of metastases was supposed to be achieved; STR could be considered. WBRT was a suitable method after neurosurgery in the patients without lung metastases but could not prolong OS in the patients with lung metastases.

Epidemiology of Intracranial Metastases in Korea: A National Cohort Investigation

PURPOSE

To investigate the epidemiologic features of intracranial metastases (ICMET) in Korea, we performed a cohort study using the National Health Insurance Service-National Sample Cohort database, which comprised healthcare usage information of approximately 1 million Korean individuals over 12 years.

MATERIALS AND METHODS

We enrolled 998,602 subjects, after excluding 18,218 subjects diagnosed with any cancer during the washout period (2002-2004). The observation period was 9 years (2005-2013; 8,725,438 person-years). The initial diagnosis date of ICMET and the primary cancer was recorded. The incidence was determined based on the number of incident cases and observation size, whereas survival was estimated using death statistics from the database.

RESULTS

Through observation period, a total 776 subjects developed ICMET. The age-standardized incidence of ICMET was 8.2 per 100,000 person-years. The mean interval between the initial diagnosis date of the primary cancer and ICMET was 13.1 months. Patients with ICMET had shorter survival than those without ICMET (30.9 months vs. 81.4 months, p < 0.001). The ICMET incidence among the cancer patients was 5.0 per 1,000 person-years; it was highest in lung cancer cases, followed by breast and liver cancer cases. Moreover, ICMET from lung cancer was the most common metastasis type, followed by ICMET from liver and breast cancer.

CONCLUSION

The incidence of ICMET was 8.2 per 100,000 person-years among the Korean population and 5.0 per 1,000 person-years among cancer patients. Most of the ICMET cases arose from lung cancer. ICMET also critically influenced survival in cancer patients.

Assessment of intracranial metastases from neuroendocrine tumors/carcinoma

BACKGROUND

The most common sites of origin for neuroendocrine carcinoma are gastrointestinal tract and its accessory glands, and lungs.

MATERIALS AND METHODS

One-hundred fifty cases diagnosed with metastatic brain lesions were retrieved from hospital records within 5 years. For these cases, the primary neoplasm, histopathological classification, metastasis, treatment, and fate all were studied.

RESULTS

Intracranial deposits were detected in 10%. The primary lesion was in the lungs in 87% of patients, and 1 patient in the breast and 1 in esophagus. Pathological classification of the primary lesion was Grade 2 (MIB-1: 3-20%) in 1 patient and neuroendocrine carcinoma (MIB-1: ≥21%) in 14 patients. The median period from onset of the primary lesion up to diagnosis of brain metastasis was 12.8 months. About 33% of patients had a single metastasis whereas 67% patients had multiple metastases. Brain metastasis was extirpated in 33% of patients. Stereotactic radiotherapy alone was administered in 20% of patients, and brain metastasis was favorably controlled in most of the patients with coadministration of cranial irradiation as appropriate. The median survival period from diagnosis of brain metastasis was 8.1 months.

CONCLUSION

Most of patients with brain metastasis from neuroendocrine carcinoma showed the primary lesion in the lungs, and they had multiple metastases to the liver, lymph nodes, bones, and so forth at the time of diagnosis of brain metastasis. The guidelines for accurate diagnosis and treatment of neuroendocrine carcinoma should be immediately established based on further analyses of those patients with brain metastasis.

Intracranial metastasis of adenocarcinoma of the prostate presenting with symptoms of spinal cord compression

Spinal cord compression is a not uncommon complication of metastatic prostate cancer. Intracranial metastasis of prostatic adenocarcinoma is however unusual. We report a case of a 67-year-old man with metastatic prostate carcinoma, who presented with a 3-day history of lower limb weakness and collapse. Neurological assessment demonstrated increased tone and reduced power in both legs. As he had typical signs and symptoms of spinal cord compression, an MRI of the spine was performed; this demonstrated no evidence of cord compression. A subsequent CT of the brain demonstrated an extensive parafalcine metastasis. This revealed an extensive enhancing mass extending bilaterally along almost the entire length of the falx cerebri, measuring up to 3 cm in width and associated with marked white matter oedema in the adjacent brain bilaterally. Unfortunately, this man succumbed to his illness a few days later. The imaging findings are presented and highlight the importance of brain imaging in patients presenting with suspected cord compression due to prostatic metastatic disease when MR of the spine shows no evidence of cord compression.