Proliferative potential of brain metastases

Radiosurgery in the treatment of brain metastases: critical review regarding complications

Stereotactic radiosurgery (SRS) has been described as an effective treatment option for brain metastases. In general, SRS has been indicated for the treatment of lesions smaller than 3 cm in maximum diameter and for lesions considered not surgically treatable, owing to the patient's clinical status or because the lesion was located in or near eloquent brain areas. In several studies, SRS has been associated with clinical and radiographic improvement of the lesions and has been compared with surgery as the modality of choice for brain metastases. Beyond the high rate of local disease control with SRS, the few complications that have been described occurred mainly in the acute post treatment period. Most publications have addressed the outcome and effectiveness of this treatment modality but have not critically analyzed long-term complications, steroid dependency, or results relating to specific brain locations. It is important to understand the radiobiologic effects of a well-demarcated high dose of radiation on the brain lesion, controlling the tumor growth and not causing significant alteration of the related brain region, especially in an area controlling eloquent function.

Brain metastases in breast cancer: prognostic factors and management

In this retrospective study, 162 breast cancer patients were analysed in whom brain metastases had been diagnosed clinically between 1969 and 1995 at a single institution. 145 patients were treated with megavoltage irradiation (60 cobalt or 6MV) of the whole brain using opposed fields. The most common applied schedule consisted of 30 Gy in 15 daily fractions over 3 weeks. 10 patients underwent surgery and 17 patients received symptomatic treatment only. The median age was 50 years (range 30-78 years). 81 of 162 patients (50%) were premenopausal. Women younger than 40 years of age had a shorter survival (median 12 weeks) than those of all other groups (median 29 weeks). Median survival was 82 weeks for the 10 surgical patients, 26 weeks for the 145 patients treated with radiotherapy and 5 weeks for the patients who received symptomatic (corticosteroid) therapy only. Patients with solitary metastases treated with radiation alone (45 patients) had a survival of 44 weeks versus 23 weeks in patients with multiple brain metastases. Multivariate stepwise regression analyses revealed Karnofsky Index, dose of radiation (P < 0.001), solitary metastases (P < 0.04) and primary tumour size (P < 0.04) as significant prognostic factors for survival.

Imaging techniques in neoplastic meningiosis

Since the introduction of CT and MRI as diagnostic aids, it has been possible to obtain direct images of neoplastic meningiosis. After more than ten years experience, the combination of MRI with the administration of a paramagnetic contrast medium is now accepted as the method of choice for the sensitive detection of meningeal diseases and for monitoring their treatment. The almost uniform character of leptomeningeal or pachymeningeal enhancement in the presence of infective, inflammatory, neoplastic, vascular or reactive changes is the reason for the restricted specificity of MRI, so that with the imaging process alone only very limited information about the etiology is available. Clinical data, laboratory findings, examination of the CSF and histopathological examination are therefore essential for interpreting the meningeal changes and making a differential diagnosis. Various pathophysiological processes can lead to a single meningeal enhancement visualizable with MRI: 1. a genuine disturbance of the blood-brain barrier is found in the presence of infection or inflammation, 2. leptomeningeal structures can be directly infiltrated by sheets or nodules of tumors, the blood vessels of which possess no intact blood-brain barrier, 3. physical or chemical irritants may produce of local inflammatory reaction with vascular proliferation and its corresponding enhancement, a 4. a pseudoenhancement may follow reactive dilatation of the vessels. In the present article the various appearances of neoplastic invasion of the meninges in MRI and their differential diagnosis will be described.

Results of a randomized comparison of radiotherapy and bromodeoxyuridine with radiotherapy alone for brain metastases: report of RTOG trial 89-05

PURPOSE

To determine if the addition of bromodeoxyuridine (BrdUrd) to radiotherapy prolongs survival when compared to radiotherapy alone in patients with brain metastases.

METHODS AND MATERIALS

Seventy-two patients with brain metastases were randomized to 37.5 Gy in 15 fractions of 2.5 Gy or to the same dose with BrdUrd 0.8 g/m2 per day for 4 days of each of 3 weeks. Drug treatment was begun on Thursday or Friday before the first week of radiotherapy. Patients had a Karnofsky performance score of at least 70, a neurological function classification of 1 or 2, and any primary tumor except central nervous system (CNS), leukemia, or lymphoma. The primary was absent, controlled, or under active radiotherapy. Patients were free of other metastases. They were stratified by primary site (breast, lung or other), number of metastases (single or multiple) and age (< 60 vs. > 60).

RESULTS

There was no significant difference between the two treatment arms (p = 0.904). The study was open from October 1989 to March 1993 and accrued 72 patients. Only one patient in the RT only arm remains alive. The two treatment arms were balanced with respect to all stratification variables. Toxicity due to radiotherapy was similar in both arms. BrdUrd caused significant Grade 4 and 5 hematologic and skin toxicity in five patients. Two patients died due to hematologic toxicity and one from a Stevens-Johnson type skin reaction. Phenytoin played a role in the skin reactions and ranitidine was associated with the hematologic deaths. Ranitidine was eliminated, BrdUrd was discontinued after any hematologic toxicity, and no further Grade 4 or 5 toxicities were seen. The median survival was 6.12 months in the radiotherapy group and 4.3 in the BrdUrd group (p = 0.904). Patients with solitary brain metastases had significantly better survival (p = 0.031).

CONCLUSIONS

BrdUrd did not enhance the efficacy of the radiotherapy regimen tested, in spite of the fact that brain metastases have shown high labeling indices. The toxicity of this schedule of BrdUrd administration was apparently increased by ranitidine and phenytoin.

Single brain metastases from unknown primary malignancies in CT-era

Cerebral metastases account for about half of all intracranial neoplasms. In 33%-66% they represent the first sign of a systemic tumor. We report our experience in 100 patients with solitary brain metastasis from unknown primary malignancies treated between 1976 and 1988. All patients were treated surgically and 81 also received radiotherapy and chemotherapy. Postoperative mortality was 6%. Mean survival in those patients with unknown primary tumor at intracranial surgery was 15.3 months as compared to 31.6 months in those in whom it remained unidentified during life. The usual cause of death was growth of the systemic cancer.

The development and progression of adenocarcinoma of the lung

This chapter has briefly reviewed the development and progression of peripheral-type adenocarcinoma of the lung, focusing particularly on bronchioloalveolar carcinoma consisting of the nonmucus-producing cell type with or without sclerosis. Histoloical examination reveals that scar cancers are rare except in cases of diffuse pulmonary fibrosis and that many nonmucus-producing bronchioloalveolar carcinomas appear to develop from atypical adenomatous hyperplasia, which can be called adenoma or very well-differentiated adenocarcinoma, and to progress stepwise. Stepwise progression in malignancy can be disclosed not only by cytological and histological examination but also by proliferative activity of the tumor, such as mitotic activity, the percentage of DNA-synthesizing cells and the frequency of proliferating cell nuclear antigen-positive cells, the mean nuclear DNA content of tumor cells and occurrence of aneuploid cell lines, and abnormalities of oncogenes (c-Ki-ras, myc family, and c-erbB2), such as point mutation, rearrangement, amplification, and tumor suppressor genes (point mutation and deletion) such as p53.

Central nervous system metastases in breast cancer

Sixty-two breast cancer patients with central nervous system (CNS) metastases were reviewed. The CNS was the first site of metastatic involvement in 38 cases (61%). The median survival from the primary diagnosis was 3.0 years; from the diagnosis of the CNS metastasis, 6 months. The interval between primary diagnosis and CNS metastasis had a median value of 2.0 years; between the initial extra-cranial metastasis and CNS metastasis this was 0.9 years. Prognostic factors for the appearance of CNS metastasis could not be identified. Subsequent to CNS metastasis appearing, the well-known prognostic factors for the survival time and the metastasis-free interval lose their importance. Brain metastases occur, above all, in patients aged between 50 and 55 years, very often in the first 2.5 years after the first distant metastasis and not later than 10 years from the primary diagnosis.

Cytofluorometric analysis of metastases from lung adenocarcinoma with special reference to the difference between hematogenous and lymphatic metastases

Metastatic tumors in the brain, liver, and regional lymph nodes (20 cases each) from patients with adenocarcinoma of the lung were examined by cytofluorometric analysis, and compared with the respective primary lung tumors. The nuclear DNA content of tumor cells was significantly increased in metastatic tumors in the brain and liver compared with the primary (P less than 0.01). However, the DNA content of metastatic tumors in regional lymph nodes was almost identical to that of the primary tumor in many instances. From the viewpoint of the nuclear DNA content of lung adenocarcinoma, blood-borne tumor cells in the brain and liver were considered likely to constitute a discrete tumor cell subpopulation, i.e., probably a more malignant one, different from the major subpopulation in the primary tumor, whereas lymphatic metastases in regional lymph nodes were similar to the primary. The subpopulation with an increased DNA content in hematogenous metastases were thought to have originated from a minor subpopulation in the primary tumor or to have developed at the metastatic site.

Immunocytochemical detection of sulphonylated DNA in tissue sections. An alternative to Feulgen staining of DNA

We report here on a new sensitive and highly specific DNA staining technique which we have called sulpho-DNA staining. DNA staining is based on a sulphonylation reaction of 2'-deoxycytidine or cytidine that takes place in the 6th position of cytosine with ensuing immunodetection of the sulphonylated DNA. The specificity of DNA staining is introduced by the use of an antibody recognizing only modified DNA but not modified RNA, by recourse to an additional acid hydrolysis step which destroys RNA but not DNA. We describe here the optimal conditions for the sulphonylation of DNA using O-methylhydroxylamine and metabisulphite as reactants. The new DNA stain labels all nuclei in either normal human tissue or in tumor cells. For nuclear DNA the staining signal is higher for the sulpho-DNA staining than for the Feulgen staining for nuclear DNA. This new DNA staining technique is suitable for use on tissue sections as well as on cytosmears.