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The analysis is based on 122 of 143 previously untreated patients with NPC treated with radiation therapy at The University of Texas M. D. Anderson Cancer Center between 1983 and 1992. Excluded were 4 patients treated with palliative intent, 4 children, 12 patients not staged with CT, and 1 patients who died of a cerebrovascular accident prior to completion of treatment. The stage distribution was as follows: AJCC Stage I---2; Stage II---7, Stage III---12, Stage IV---101; T1---15; T2---33, T3---22; T4---52; N0---32; N1---10; N2---47, N3---32, Nx---1. Fifty-nine (48%) patients has sqamous cell carcinoma; 63 (52%) had lymphoepitheliomas, undifferentiated NPC or poorly differentiated carcinoma, NOS (UNPC). Sicty-seven patients (65 with Stage IV disease) received induction chemotherapy. Fifty-eight patients (24 of whom had induction chemotherapy) were treated with the concomitant boost fractionation schedule. The median follow-up for surviving patients was 57 months.
The overall actuarial 2- and 5-year survival rates were 78 and 68%, respectively. Forty-nine patients (40%) has disease recurrence. Thirty-three (27%) had local regional failures; 19 at the primary site only, 8 in the neck and 6 in both. Local failure occurred in 31% of patients staged T4 compared to 13% of T1–T3 (p = 0.007). Sixteen patients failed at distant sites alone. Among Stage IV patients the 5-year actuarial rates for patients who did and did not receive induction chemotherapy were as follows: overall survival: 68 vs. 56% p = 0.02), freedom from relapse; 64 vs. 37% (p = 0.01), and local control: 86 vs. 56% (p = 0.009). The actuarial 5-year distant failure rate in patients with UNPC who were treated with induction chemotherapy and controlled in the primary and neck was 13%. In patients who did not receive chemotherapy, the acturial 5-year local control rates for patients treated with concomitant boost or conventional fractionation were 66 and 67%, respectively.
While not providing conclusive evidence, this single institution experience suggests that neoadjuvant chemotherapy for Stage IV NPC patients improves both survival and disease control. Recurrence within the irradiated volume was the most prevalent mode of failure and future studies will evaluate regimens to enhance local regional control. 相似文献
The purpose of the present study was to assess brain tissue monitoring for detection of ischemia due to vasospasm in aneurysmal subarachnoid hemorrhage (SAH) patients.
METHODS
After obtaining informed consent, a burr hole was made in 10 patients and a Neurotrend 7 probe was inserted ipsilateral to the region of SAH. In eight patients the probe was inserted during surgery for clipping the aneurysm and in two patients the probe was inserted in the neurosurgery ICU. Brain tissue gases and pH were collected over 6-hour periods for 7 to 10 days until the termination of monitoring. The onset of vasospasm was confirmed by angiography and xenon computed tomography (Xe/CT) cerebral blood flow studies.
RESULTS
Seven patients did not develop vasospasm during monitoring and were considered as controls. In this group, brain tissue oxygen pressure (PO2) remained above 20 mmHg, carbon dioxide pressure (PCO2) stabilized at 40 mmHg and pH remained between 7.1 and 7.2. In three patients who developed vasospasm during monitoring, PO2 was not different from the control group. However, PCO2 increased to 60 mmHg and pH decreased to 6.7 (p < 0.001).
CONCLUSION
In this study, patients with SAH who developed vasospasm had significantly lower brain tissue pH and higher PCO2 compared to controls. However, there was no significant change in PO2 levels associated with vasospasm. Brain tissue monitoring can provide an indication of ischemia during vasospasm. 相似文献