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B C Wen

Publications and source records attributed to B C Wen.

At least 37 records · Page 2Linked to original sources
PubMed1994

Cost-effectiveness of high-dose MR contrast studies in the evaluation of brain metastases.

PURPOSE: To investigate the cost-effectiveness of high-dose MR contrast studies in the management of brain metastases. METHODS: During the phase III clinical trial of high-dose contrast studies (0.3 mmol/kg), 11 of 27 patients were judged by the reviewers to have potential treatment changes based on the additional information provided by the high-dose studies. We retrospectively evaluated how many of these 27 patients had actual treatment changes because of the results of the high-dose study. Using the fee schedule at our institution, the cost-effectiveness was analyzed based on the cost savings from treatment changes and the additional expense of implementing the high-dose studies. RESULTS: A total of 3 craniotomies ($22,800 each) and 2 aggressive courses of radiation therapy ($1122 each) were avoided in 4 patients because of the additional lesions detected by the high-dose studies. This resulted in a treatment cost savings of $70,644. The extra expense for implementing the high-dose study is $9126 for a single injection in all 27 patients, $9295 for 2 separate injections completed in 1 visit in the 11 patients, and $11,154 for 2 separate injections completed in 2 separate visits. The cost savings in management (diagnosis and treatment) therefore ranged from $59,490 to $61,518 for all patients and from $2203 to $2278 per patient. CONCLUSION: Based on our limited data, the high-dose study seems to impact positively on the cost-effectiveness in the management of brain metastases. However, because our study had limitations, our results need to be confirmed with a larger patient population and a more standardized treatment approach and fee schedule.

Adult↗
PubMed1993

Cervical cancer: application of MR imaging in radiation therapy.

PURPOSE: To evaluate magnetic resonance (MR) imaging in the planning of radiation therapy for patients with cervical cancer. MATERIALS AND METHODS: MR imaging was performed in 15 patients with predominantly advanced cervical carcinomas. Skin markings of the radiation ports were labeled with MR-detectable tubing and beads to assess the adequacy of port placement. Volume and extent of tumor at MR imaging were compared with those at physical and computed tomographic (CT) examinations. RESULTS: Tumor involvement of normal structures (parametrium, vagina, endometrium) was more extensive at MR imaging than at clinical examination in six patients (40%) and at CT in five patients (33%), resulting in modification of the radiation fields in eight patients (53%). Tumor size was larger on MR images than at clinical examination in 11 patients (73%). CONCLUSION: MR imaging can depict tumor volume and better delineate the extent of involvement than physical and CT examination. This can be useful for placement of radiation ports, especially when small boost fields are used.

Adult↗
PubMed1992

Leptomeningeal carcinomatosis following craniofacial resection of an ethmoid tumor.

Leptomeningeal carcinomatosis (LMC) is a rare complication following treatment for head and neck cancer. In this paper, we report a case of LMC following surgery and localized radiation therapy for an ethmoid carcinoma, in which laceration of the dura during craniofacial resection may have provided an access for cancer cells into the cerebrospinal fluid (CSF). As a result, the patient developed LMC manifested as multiple spinal nerve root involvement. The patient died 3 months after the diagnosis of LMC. To avoid this type of complication, special care must be taken to prevent tears in the dura during craniofacial resection. Also, we recommend CSF examination be performed prior to radical surgery if there is any suspicion of meningeal invasion.

Adenocarcinoma↗
PubMed1992

Extended field irradiation for carcinoma of the uterine cervix with positive periaortic nodes.

Forty-three patients were treated with extended field irradiation for periaortic metastasis from carcinoma of the uterine cervix (FIGO stages IB-IV). Twelve patients (28%) remained continuously free of disease to the time of analysis or death from intercurrent disease, 20 (46%) had persistent cancer within the pelvis, 11 (26%) had persistent periaortic disease, and 23 (53%) developed distant metastasis. The actuarial 5-year survival rate was 32%. The results correlated well with the periaortic tumor burden at the time of irradiation. None of 19 patients (0%) with microscopic or small (less than 2 cm) periaortic disease had periaortic failures, compared to 29% (4/14) of those with moderate-sized (2-5 cm) disease and 70% (7/10) of those with massive (greater than 5 cm) periaortic metastasis. Similarly, the 5-year survival rates were 50% (6/12) with microscopic disease, 33% (2/6) with small gross disease, 23% (3/13) with moderate-sized disease, and 0% (0/10) with massive periaortic metastases. Only 10% (1/10) of patients whose tumor extended to the L1-2 level survived 5 years, compared with 31% (9/29) of those whose disease extended no higher than the L3-4 level. The periaortic failure rates correlated to some extent with the dose delivered through extended fields, although the difference was not statistically significant. Only 8% (1/13) of those who had undergone extraperitoneal lymphadenectomies developed small bowel complications, compared with 25% (7/29) of those who had had transperitoneal lymphadenectomies. The incidence of small bowel obstruction was 8% (1/13) following periaortic doses of 4000-4500 cGy, 10% (1/10) after 5000 cGy, and 32% (6/19) after approximately 5500 cGy. From this, we concluded that the subset of patients who would benefit most from extended field irradiation are those in whom the residual disease in the periaortic area measures less than 2 cm in size at the time of treatment, whose disease extends no higher than L3, and whose cancer within the pelvis has a reasonable chance of control with standard radiation therapy techniques.

Adult↗
PubMed1992

Results of radical perineal prostatectomy with adjuvant brachytherapy.

Retrospective analysis of outcome in 137 patients who underwent radical perineal prostatectomy and bilateral injection of gold-198 implants into the periprostatic tissues and/or neurovascular pedicles as treatment for prostatic adenocarcinoma was performed. Patients had undergone treatment between 1975 and 1985. Local recurrence developed in 22 patients (16.1%) and distant metastases developed in 33 (24.1%). Clinical and surgical staging of disease and Gleason grading of pathologic specimens were performed retrospectively. Kaplan-Meier local recurrence, freedom from relapse (FFR), and survival rates decreased with increasing stage and pathologic grade. With clinical staging, these rates were not statistically different from previous rates achieved with external beam radiation therapy, and with pathologic staging, they were not statistically different from previous rates achieved with prostatectomy. The authors conclude that (a) 5-year follow-up is inadequate to determine local control rates after prostatectomy; (b) use of implants did not improve local control, FFR, or survival rates of 10 years; and (c) method of staging probably has more effect on local control, FFR, and survival rates than does treatment modality.

Adenocarcinoma↗
PubMed1992

Brachytherapy for malignant recurrent and untreated gliomas.

Twelve consecutive patients with recurrent malignant glioma were treated with brachytherapy. Thereafter, a prospective randomized study involving 35 patients was undertaken. Although additional study is necessary, preliminary recommendation calls for treatment at diagnosis rather than at recurrence.

Astrocytoma↗
PubMed1991

Heritable retinoblastoma and pinealoma.

A fourth case of bilateral retinoblastoma (RB) associated with pinealoma was identified among 56 patients with heritable RB. Using life-table analysis, the association was 5.6% 2 years after RB diagnosis. Retinoblastoma-pinealoma (RB-P) was uniformly fatal in this series and in 40 additional patients described in the literature. Ninety-five percent of patients with RB-P had bilateral RB, a positive family history of RB, or both. All patients with pinealoma presented with symptoms of increased intracranial pressure due to obstructive hydrocephalus. The advanced stage of the tumors at diagnosis may contribute to their uniform lethality. The incidence of a positive family history of RB in patients with pinealoma was higher than expected (62% of patients), which may be related to earlier surveillance and treatment of patients with positive family histories of RB.

Brain Neoplasms↗
PubMed1991

The role of radiation therapy in the management of ependymomas of the spinal cord.

Twenty patients with biopsy-proven ependymomas of the spinal cord were treated between 1960 and 1984-7 with surgery only, 3 with radiation therapy only, and 10 with surgery and postoperative radiation therapy. Of these, 2 patients developed recurrent tumor at the primary site, 3 developed a recurrent tumor in the thecal sac, and 1 developed distant metastasis. The absolute 5- and 10-year survival rates were 95% (19/20) and 86% (12/14), respectively. None of 13 patients who were treated with radiation therapy only or combined surgery and postoperative radiation therapy developed recurrent tumor at the primary site, and none of 7 patients who received thecal sac irradiation developed thecal sac recurrences. In contrast, 2 of 7 patients (29%) treated with surgery alone developed recurrent tumor at the primary site, and 3 of 13 patients (23%) who received no thecal sac irradiation developed a recurrent tumor in the thecal sac. The failure rates following surgery were greatest in patients who had tumor removed in a piecemeal fashion (43%, 6/14). The results show that radiation therapy is probably not necessary if the tumor has been removed completely in an en bloc fashion. However, radiation therapy is needed if the tumor has been incompletely removed or removed in a piecemeal fashion. If the tumor has been removed in a piecemeal fashion, the radiation portals should be extended to include the thecal sac. Histologic subtypes influenced the pattern of recurrence. Myxopapillary ependymomas and high grade cellular ependymomas appear to be more likely to recur in the thecal sac. However, no big difference could be detected in local recurrence.

Adolescent↗
PubMed1991

A comparison of the roles of surgery and radiation therapy in the management of carcinoma of the female urethra.

Between 1939 and 1986, 42 patients with carcinoma of the female urethra were treated with surgery and/or radiation therapy at the University of Iowa. Ten patients were treated with surgery alone, 28 with radiation therapy alone, and 4 with combined surgery and radiation therapy. Seventeen patients (40%) developed persistent or recurrent disease at the primary site and 15 (36%) had failures in the inguinal nodes. The actuarial 5-year survival rate was 33.5%. Only 36% (10/28) of patients treated with radiation therapy had local failures, compared to 60% (6/10) of those treated with surgery alone. The best results were achieved with combined interstitial and external beam irradiation. Whereas 57% (8/14) of patients who were treated with combined interstitial and external beam irradiation were alive NED at 3 years, none of 7 patients (0%) treated with interstitial implants only and 2 of 7 patients (29%) treated with external beam irradiation alone were alive NED at 3 years. There was a significantly lower inguinal failure rate in patients who received treatment to the inguinal nodes (10%) than in those who did not receive inguinal area treatment (52%), and this translated into a superior 5-year survival for those patients (60% vs 18%). Survival rates did not correlate with histopathologic type in this series, although there were differences in the patterns of failure. Survival rates did correlate well with clinical stage.

Adenocarcinoma↗
PubMed1991

Magnetic resonance imaging of peripheral T-cell lymphoma.

We report magnetic resonance (MR) findings of two unusual cases of peripheral T-cell lymphoma, one initially presenting as a soft-tissue mass in the neck and the other in the foot. MR imaging provides better tissue contrast and lesion delineation than CT. However, MR signal characteristics cannot differentiate this lymphoma from other soft-tissue tumours. Although it is rare, peripheral T-cell lymphoma should be included in the differential diagnosis of a soft-tissue mass.

Foot↗
PubMed1990

BVAC ablative chemotherapy followed by autologous bone marrow transplantation for patients with advanced lymphoma.

Forty-one consecutive patients with lymphoma resistant to conventional combination chemotherapy have been entered into a study in which chemo-ablative therapy and autologous marrow rescue were used with curative intent. The actuarial proportion of 20 patients with Hodgkin's lymphoma remaining alive and free of recurrent disease is 49%, while that for 21 patients with non-Hodgkin's lymphoma is 41%. Our clinical approach to these patients involved a strategy whereby lymphomatous nodes greater than 2 cm in diameter that persisted despite salvage chemotherapy were given boost radiation therapy immediately before chemo-ablation. However, patients with this variable had a significantly lower survival due to septic complications rather than recurrent disease. We conclude that the treatment strategy used in this study with some modification may improve further on the already high probability of long-term disease-free survival experienced by this group of patients.

Adolescent↗
PubMed1990

The role of radiation therapy in the treatment of solitary plasmacytomas.

Between 1960 and 1985, 30 patients with solitary plasmacytomas were treated with radiotherapy at the University of Iowa: 13 patients with extramedullary plasmacytomas (EMP) and 17 with solitary plasmacytomas of bone (SPB). The local control rates were 92% for patients with EMP and 88% for those with SPB. Two of nine patients (22%) with EMP treated to the primary tumor only developed regional lymph node metastasis, indicating the need for elective irradiation of this area. The most common pattern of failure in both groups was progression to multiple myeloma. This occurred in 23% of the patients with EMP and 53% of those with SPB. The time course of progression to multiple myeloma differed for the two groups. All of those who progressed to multiple myeloma in the EMP group did so within 2 years, whereas a significant number of those in the SPB group progressed more than 5 years after initial therapy. None of five patients who received adjuvant chemotherapy in the SPB group progressed to multiple myeloma, compared to 75% (9/12) of the patients who did not receive chemotherapy.

Adult↗
PubMed1990

The role of kilovoltage irradiation in the treatment of keloids.

This is a retrospective analysis of the results of kilovoltage irradiation given to prevent the regrowth of 203 keloids excised at the University of Iowa Hospitals and Clinics, Iowa City, Iowa, Lutheran Hospital in Moline, Illinois, and Mercy Hospital in Cedar Rapids, Iowa. We found that a minimum follow-up of 1 year is needed to evaluate the results of post-excisional kilovoltage x-ray therapy. A dose versus response effect was also observed. Although it is desirable to use the lowest possible dose of radiation that is likely to be effective, the likelihood of failure is too great to justify the routine use of doses of less than 900 cGy regardless of how they are fractionated or when they are given. It appears that the total dose of irradiation that is given to prevent the regrowth of an excised keloid is more important than when irradiation is started, the size of the largest fraction given, whether the irradiation is completed in 1 week or 3, or where the keloid has grown. When a small number of keloids were irradiated less than 1 year after they first appeared greater than or equal to 1500 cGy were sufficient to control 90% of them without re-excision.

Adolescent↗
PubMed1990

Preliminary results of a pilot study of pentoxifylline in the treatment of late radiation soft tissue necrosis.

Between September 1988 and August 1989, 12 patients with 15 sites of late radiation necrosis of the soft tissues were treated with pentoxifylline, a hemorrheologic agent that has been used to treat a variety of vasculo-occlusive disorders. Four of these necroses were located in the oromucosa, four in the mucosa of the female genitalia, and seven in the skin. At the time of analysis, 87% (13/15) of the necroses had healed completely, and one was partially healed. Furthermore, the time-course of healing with pentoxifylline was significantly less than the duration of nonhealing prior to pentoxifylline (average: 9 weeks vs 30 1/2 weeks). All patients had pain relief. These results indicate that pentoxifylline can contribute to the healing of soft tissue radiation necrosis. They also support the concept that late radiation injury in skin and mucosa is at least partly due to vascular injury.

Adult↗
PubMed1990

Hemangiopericytoma--the role of radiotherapy.

Between 1955 and 1987, 15 patients with hemangiopericytomas were seen at the University of Iowa Hospitals and Clinics. Twelve of these were thought to have localized tumors and three had metastatic disease at diagnosis. Seven of the 12 patients with localized disease were treated with surgery alone, four were treated with surgery and postoperative radiation therapy, and one was treated with surgery and chemotherapy. Only one of the seven patients initially treated with surgery alone has remained continuously free of disease, although two others were salvaged with radiation therapy. In contrast, all four patients initially treated with surgery and postoperative radiation therapy have remained alive with no evidence of disease in spite of the fact that three of these patients had gross residual tumor at the time of irradiation. Ten patients received radiation therapy at some stage of their management. Local tumor control was achieved at all sites receiving greater than 5500 cGy. Six patients received chemotherapy sometime during the course of their management, although no complete or partial responses were observed. In this small series, mitotic activity was not an accurate predictor of biologic behavior.

Adolescent↗
PubMed1990

Bone marrow transplantation improves survival for acute lymphoblastic leukemia in relapse: a preliminary report.

Acute lymphoblastic leukemia of childhood is the most common malignant disease in children greater than 1 year of age. Chemotherapy has improved the survival of children with this disorder. More than 95% of children will achieve a remission with chemotherapy. However, 30% of children with acute lymphoblastic leukemia who achieved a remission will have a relapse sometime after successful remission-inducing chemotherapy. Although a second remission can be induced in most of these children, in 10-40% a remission cannot be induced or they relapse shortly thereafter and develop refractory leukemia. We present in this preliminary report the early results of therapy for refractory leukemia with an intensive preparative regimen for bone marrow transplantation including etoposide, cytosine arabinoside, cyclophosphamide, and fractionated total body irradiation. Transplantation was done in twenty-three patients with refractory leukemia. Projected survival at 917 days after transplantation in these patients is 43.4% +/- 11%. The survival of these patients so far is similar to the survival of children with acute lymphoblastic leukemia transplanted in second remission. All patients treated with this regimen who had transplantation in relapse were free of leukemia 27 days after transplantation. The results of this preliminary report suggest that an intensive preparative regimen can improve the outlook of refractory leukemia and may rescue some patients who otherwise would have died of their disease.

Adolescent↗
PubMed1989

A comparison of the roles of surgery and radiation therapy in the management of craniopharyngiomas.

Fifty-two patients with craniopharyngioma were seen between January 1961 and July 1986. Of these, 40 were treated with surgery alone, 8 with surgery and postoperative radiotherapy, and 3 with radiotherapy alone. One patient received no treatment. For the group treated with surgery alone, 33% (13/40) had local tumor control, 42.5% (17/40) developed major complications, and 71% (25/35) survived 5 years. With surgery and postoperative radiotherapy, 100% (8/8) had local tumor control, 25% (2/8) developed major complications, and 100% (7/7) survived 5 years. Two of the three patients treated with radiotherapy alone had local tumor control and the third was salvaged with surgery. The "complete resection" rate for 32 patients treated with radical surgery was 63% (20/32). Tumor control was achieved in 50% (10/20) of the patients treated with "complete resection" without radiotherapy, in 15% (3/20) of the patients treated with "incomplete resection" without radiotherapy, and in 100% (8/8) of the patients treated with "incomplete resection" and postoperative radiotherapy. In this series, doses of 5000-5500 cGy were as effective in achieving control as 5500-6000 or 6000-7000 cGy.

Adolescent↗