Leptomeningeal carcinomatosis in non-small-cell lung cancer patients: impact on survival and correlated prognostic factors.

BACKGROUND: The incidence of leptomeningeal carcinomatosis (LC) has increased in patients with metastatic non-small-cell lung cancer (NSCLC) because of recent improvements in survival. The clinical features and prognostic factors of LC in NSCLC patients, however, have not been well identified. The aim of this study was to identify the clinical features and prognostic factors of NSCLC patients with LC. METHODS: One hundred and forty-nine consecutive NSCLC patients with cytologically proven LC diagnoses between 2001 and 2009 at Samsung Medical Center were retrospectively reviewed. RESULTS: The median age was 58 years (range, 34-80) with most patients (135, 95%) having histology indicating adenocarcinoma. Twenty-six patients (17.4%) had LC at the initial presentation of lung cancer. Treatment for LC consisted of intrathecal chemotherapy (ITC) alone in 44 patients, ITC plus systemic therapy in 18 patients, ITC plus radiotherapy in 29 patients, all three treatments in 18 patients, and other treatments without ITC in 20 patients. Twenty patients received only supportive care. The median follow-up duration was 34 months and the median overall survival from diagnosis of LC was 14 weeks (95% confidence interval [CI] 12, 16). In univariate analysis, encephalopathy, Eastern Cooperative Oncology Group (ECOG) performance status, low initial cerebrospinal fluid (CSF) glucose, high initial CSF protein, high initial CSF white blood cell count, treatment with ITC, systemic therapy with epidermal growth factor receptor tyrosine kinase inhibitors or cytotoxic chemotherapy, whole-brain radiotherapy (WBRT), ventriculoperitoneal (VP) shunt operations, and negative cytologic conversion after ITC were identified as variables that had prognostic influence on survival. In multivariate analysis, poor ECOG performance status (p = 0.026), high protein level of CSF (p = 0.027), and high initial CSF WBC count (p = 0.015) remained significant predictors of poor prognosis for survival, whereas ITC (p < 0.001), EGFR-TKI use (p = 0.018), WBRT (p = 0.009), and VP shunt operation (p = 0.013) remained significant predictors of favorable prognosis for survival. CONCLUSIONS: Even though the prognosis of LC from NSCLC is poor, small subsets of these patients survive longer. Our results suggest that more active treatment strategies including ITC, WBRT, and EGFR-TKI use might improve clinical outcomes in NSCLC patients with LC and good performance status, low initial CSF protein and WBC counts.

Analysis of changes in dose distribution due to respiration during IMRT.

PURPOSE: Intensity modulated radiation therapy (IMRT) is a high precision therapy technique that can achieve a conformal dose distribution on a given target. However, organ motion induced by respiration can result in significant dosimetric error. Therefore, this study explores the dosimetric error that result from various patterns of respiration. MATERIALS AND METHODS: Experiments were designed to deliver a treatment plan made for a real patient to an in-house developed motion phantom. The motion pattern; the amplitude and period as well as inhale-exhale period, could be controlled by in-house developed software. Dose distribution was measured using EDR2 film and analysis was performed by RIT113 software. Three respiratory patterns were generated for the purpose of this study; first the 'even inhale-exhale pattern', second the slightly long exhale pattern (0.35 seconds longer than inhale period) named 'general signal pattern', and third a 'long exhale pattern' (0.7 seconds longer than inhale period). One dimensional dose profile comparisons and gamma index analysis on 2 dimensions were performed RESULTS: In one-dimensional dose profile comparisons, 5% in the target and 30% dose difference at the boundary were observed in the long exhale pattern. The center of high dose region in the profile was shifted 1 mm to inhale (caudal) direction for the 'even inhale-exhale pattern', 2 mm and 5 mm shifts to exhale (cranial) direction were observed for 'slightly long exhale pattern' and 'long exhale pattern', respectively. The areas of gamma index >1 were 11.88%, 15.11%, and 24.33% for 'even inhale-exhale pattern', 'general pattern', and 'long exhale pattern', respectively. The long exhale pattern showed largest errors. CONCLUSION: To reduce the dosimetric error due to respiratory motions, controlling patient's breathing to be closer to even inhaleexhale period is helpful with minimizing the motion amplitude.

Pelvic insufficiency fracture after pelvic irradiation in uterine cervix cancer.

OBJECTIVES: Pelvic insufficiency fractures (IF) are well known but uncommon and are frequently misinterpreted sequelae. The clinical features were investigated. METHODS: Four hundred sixty-three patients, who were treated between 1994 and 2000 for uterine cervix cancer, were clinically examined. All patients had been treated with 10 or 15 MV photons, with 50.4-55.8 Gy in 28 fractions with adjuvant intent (n = 235) in addition to high-dose-rate brachytherapy 24 Gy in 6 fractions for curative treatment (n = 228). The median follow-up was 38 months. RESULTS: Eight patients (8/463, 1.7%) developed pelvic IF 7-19 months (median, 12 months) after the treatment. Among these, seven patients (7/228, 3.1%) were treated with curative intent and one (1/235, 0.4%) was treated with adjuvant intent. All patients were postmenopausal and complained of moderate to severe pelvic pain, which resolved after 1-11 months with conservative therapy in all patients. Two of these patients also had radiation proctitis. CONCLUSION: In women who present with pelvic pain after radiotherapy for cervical cancer, bony destruction and fractures may be indicative of a late radiation effect rather than osseous metastasis. IF are more common in the curative treatment group than in the postoperative adjuvant group.