Phase III trial of neoadjuvant chemotherapy in patients with invasive bladder cancer treated with selective bladder preservation by combined radiation therapy and chemotherapy: initial results of Radiation Therapy Oncology Group 89-03

PURPOSE

To assess the efficacy of neoadjuvant methotrexate, cisplatin, and vinblastine (MCV) chemotherapy in patients with muscle-invading bladder cancer treated with selective bladder preservation.

PATIENTS AND METHODS

One hundred twenty-three eligible patients with tumor, node, metastasis system clinical stage T2 to T4aNXMO bladder cancer were randomized to receive (arm 1, n=61 ) two cycles of MCV before 39.6-Gy pelvic irradiation with concurrent cisplatin 100 mg/m2 for two courses 3 weeks apart. Patients assigned to arm 2 (n=62) did not receive MCV before concurrent cisplatin and radiation therapy. Tumor response was scored as a clinical complete response (CR) when the cystoscopic tumor-site biopsy and urine cytology results were negative. The CR patients were treated with an additional 25.2 Gy to a total of 64.8 Gy and one additional dose of cisplatin. Those with less than a CR underwent cystectomy. The median follow-up of all patients who survived is 60 months.

RESULTS

Seventy-four percent of the patients completed the protocol with, at most, minor deviations; 67% on arm 1 and 81% on arm 2. The actuarial 5-year overall survival rate was 49%; 48% in arm 1 and 49% in arm 2. Thirty-five percent of the patients had evidence of distant metastases at 5 years; 33% in arm 1 and 39% in arm 2. The 5-year survival rate with a functioning bladder was 38%, 36% in arm 1 and 40% in arm 2. None of these differences are statistically significant.

CONCLUSION

Two cycles of MCV neoadjuvant chemotherapy were not shown to increase the rate of CR over that achieved with our standard induction therapy or to increase freedom from metastatic disease. There was no impact on 5-year overall survival.

Quality assurance of serial tomotherapy for head and neck patient treatments

PURPOSE

A commercial serial tomotherapy intensity-modulated radiation therapy (IMRT) treatment planning (Peacock, NOMOS Corp., Sewickley, PA) and delivery system is in clinical use. The dose distributions are highly conformal, with large dose gradients often surrounding critical structures, and require accurate localization and dose delivery. Accelerator and patient-specific quality assurance (QA) procedures have been developed that address the localization, normalization, and delivery of the IMRT dose distributions.

METHODS AND MATERIALS

The dose distribution delivered by serial tomotherapy is highly sensitive to the accuracy of the longitudinal couch motion. There is also an unknown sensitivity of the dose distribution on the dynamic mutlileaf collimator alignment. QA procedures were implemented that assess these geometric parameters. Evaluations of patient positioning accuracy and stability were conducted by exposing portal films before (single exposure) and after (single or double exposure) treatments. The films were acquired with sequential exposures using the largest available fixed multileaf portal (3.36 x 20 cm2). Comparison was made against digitally reconstructed radiographs generated using independent software and appropriate beam geometries. The delivered dose was verified using homogeneous cubic phantoms. Radiographic film was used to determine the localization accuracy of the delivered isodose distributions, and ionization chambers and thermoluminescent dosimetry (TLD) chips were used to verify absolute dose at selected points. Ionization chamber measurements were confined to the target dose regions and TLD measurements were obtained throughout the irradiated volumes. Because many more TLD measurements were made, a statistical evaluation of the measured-to-calculated dose ratio was possible.

RESULTS

The accelerator QA techniques provided adequate monitoring of the geometric patient movement and dynamic multileaf collimator alignment and positional stability. The absolute delivered dose as measured with the ionization chamber varied from 0.94 to 0.98. Based on these measurements, the delivered monitor units for both subsequent QA measurements and patient treatments were adjusted by the ratio of measured to calculated dose. TLD measurements showed agreement, on average, with the ionization chamber measurements. The distribution of TLD measurements in the high-dose regions indicated that measured doses agreed within 4.2% standard deviation of the calculated doses. In the low-dose regions, the measured doses were on average 5% greater than the calculated doses, due to a lack of leakage dose in the dose calculation algorithm.

CONCLUSIONS

The QA system provided adequate determination of the geometric and dosimetric quantities involved in the use of IMRT for the head and neck. Ionization chamber and TLD measurements provided accurate determination of the absolute delivered dose throughout target volumes and critical structures, and radiographic film yielded precise dose distribution localization verification. Portal film acquisition and subsequent portal film analysis using 3.36 x 20 cm2 portals proved useful in the evaluation of patient immobilization quality. Adequate bony landmarks were imaged when carefully selected portals were used.

Surgical ligation of patent ductus arteriosus in very low birth weight infants: is it safe?

We evaluated the outcome of a combined medical and surgical treatment of patent ductus arteriosus (PDA) in newborns weighing less than 1500 g. Charts were retrospectively reviewed for 76 newborns with a PDA between 1993 and 1997. Thirteen infants had pre-existing conditions prohibiting the use of indomethacin; eight were managed surgically, five medically. The remaining 63 infants received indomethacin therapy. Thirty-two medical failures occurred, requiring surgical ligation of the PDA. Those requiring surgery had a lower average birth weight (847 versus 997 g) and gestational age (26 versus 28 weeks; P < 0.05). Indomethacin treatment was successful in 27 infants. There were only three operative complications: a small pneumothorax, wound bleeding, and a small aortic tear. All recovered uneventfully and no deaths were attributable to the surgical procedure itself. There was no difference in the incidence of respiratory distress syndrome, duration of intubation, sepsis, neonatal enterocolitis, renal dysfunction, bleeding disorders, or intraventricular hemorrhage among both groups. Surgical ligation of a PDA is associated with a high success rate, a low incidence of complications, and no additional morbidity than indomethacin alone. We propose that surgical ligation should be regarded as a first line therapy for very small premature infants who are at higher risk of medical failure.

Irradiation in carcinoma of the vulva: factors affecting outcome

PURPOSE

This report reviews the increasing role of radiation therapy in the management of patients with histologically confirmed vulvar carcinoma, based on a retrospective analysis of 68 patients with primary disease (2 in situ and 66 invasive) and 18 patients with recurrent tumor treated with irradiation alone or combined with surgery.

METHODS AND MATERIALS

Of the patients with primary tumors, 14 were treated with wide local excision plus irradiation, 19 received irradiation alone after biopsy, 24 were treated with radical vulvectomy followed by irradiation to the operative fields and inguinal-femoral/pelvic lymph nodes, and 11 received postoperative irradiation after partial or simple vulvectomy. The 18 patients with recurrent tumors were treated with irradiation alone. Indications and techniques of irradiation are discussed in detail.

RESULTS

In patients treated with biopsy/local excision and irradiation, local tumor control was 92% to 100% in Stages T1-3N0, 40% in similar stages with N1-3, and 27% in recurrent tumors. In patients treated with partial/radical vulvectomy and irradiation, primary tumor control was 90% in patients with T1-3 tumors and any nodal stage, 33% in patients with any T stage and N3 lymph nodes, and 66% with recurrent tumors. The actuarial 5-year disease-free survival rates were 87% for T1N0, 62% for T2-3N0, 30% for T1-3N1 disease, and 11 % for patients with recurrent tumors; there were no long-term survivors with T4 or N2-3 tumors. Four of 18 patients (22%) treated for postvulvectomy recurrent disease remain disease-free after local tumor excision and irradiation. In patients with T1-2 tumors treated with biopsy/wide tumor excision and irradiation with doses under 50 Gy, local tumor control was 75% (3 of 4), in contrast to 100% (13 of 13) with 50.1 to 65 Gy. In patients with T3-4 tumors treated with local wide excision and irradiation, tumor control was 0% with doses below 50 Gy (3 patients) and 63% (7 of 11) with 50.1 to 65 Gy. In patients with T1-2 tumors treated with partial/radical vulvectomy and irradiation, local tumor control was 83% (14 of 17), regardless of dose level, and in T3-4 tumors, it was 62% (5 of 8) with 50 to 60 Gy and 80% (8 of 10) with doses higher than 60 Gy. The differences are not statistically significant. There was no significant dose response for tumor control in the inguinal-femoral lymph nodes; doses of 50 Gy were adequate for elective treatment of nonpalpable lymph nodes, and 60 to 70 Gy controlled tumor growth in 75% to 80% of patients with N2-3 nodes when administered postoperatively after partial or radical lymph node dissection. Significant treatment morbidity included one rectovaginal fistula, one case of proctitis, one rectal stricture, four bone/skin necroses, four vaginal necroses, and one groin abscess.

CONCLUSIONS

Irradiation is playing a greater role in the management of patients with carcinoma of the vulva; combined with wide local tumor excision or used alone in T1-2 tumors, it is an alternative treatment to radical vulvectomy, with significantly less morbidity. Postradical vulvectomy irradiation in locally advanced tumors improves tumor control at the primary site and the regional lymphatics in comparison with reports of surgery alone.

A critical evaluation of the planning target volume for 3-D conformal radiotherapy of prostate cancer

PURPOSE

To determine an adequate planning target volume (PTV) margin for three-dimensional conformal radiotherapy (3D CRT) of prostate cancer, the uncertainties in the internal positions of the prostate and seminal vesicles (SV) and in the treatment setups were measured.

METHODS AND MATERIALS

Weekly computed tomography (CT) scans of the pelvis (n=51) and daily electronic portal images (n=1630) were reviewed for eight patients who received seven-field 3D CRT for prostate cancer. The CT scans were registered in three dimensions to the original planning CT scan using commercially available software to measure the center-of volume (COV) motion of the prostate and SV. The daily portal images were registered to the corresponding simulation films to measure the setup displacements. The standard deviation (SD) of the internal organ motions was added to the SD of the setups in quadrature to determine the total uncertainty. Positive directions were left, anterior, and superior. Rotations necessary to register the CT scans and portal images were minimal and not further analyzed.

RESULTS

The mean motion for the COV of the prostate+/-the SD was 0+/-0.9 mm in the left-right (LR), 0.5+/-2.6 mm in the anterior-posterior (AP), and 1.5+/-3.9 mm in the superior-inferior (SI) directions. The mean motion for the COV of the SV+/-the SD was 0.3+/-1.7 mm in the LR, 0.7+/-3.8 mm in the AP, and 0.9+/-3.5 mm in the SI directions. For all patients the mean isocenter displacement+/-the SD was 0+/-3.1 mm in the LR, 1.4+/-3.0 mm in the AP, and -0.4+/-2.1 mm in the SI directions. The total uncertainty for the prostate was 3.2 mm, 4.0 mm, and 4.4 mm in the LR, AP, and SI directions, respectively. For the SV, the total uncertainty was 3.5, 4.8, and 4.1 mm in the LR, AP, and SI directions, respectively.

CONCLUSIONS

PTV margins of 10 to 16 mm are required to encompass all (99%) possible positions of the prostate or SV during 3D CRT. PTV margins of 7 to 11 mm will encompass the measured uncertainties with a 95% probability. PTV margins of 5 mm may not adequately cover the intended volume.

Treatment planning in radiation oncology and impact on outcome of therapy

Irradiation is effective treatment for many patients with cancer. It can completely eradicate the tumor in the irradiated volume or it provides palliative relief to patients with incurable cancer. The success of radiation therapy depends on the delivery of an adequate dose to the entire tumor volume with acceptable morbidity in the surrounding normal tissues. The goals are to achieve the highest probability of local and regional tumor control with the lowest achievable incidence of side effects and to prolong the life of the patient with the best possible quality of life. Although treatment planning is extremely helpful in determining the best form of therapy, the responsibility for critical judgment and execution rests with the radiation oncologist, who, to treat patients effectively, must have sufficient training to define the target volume and critical structures, to interpret treatment planning information and to guide the physicist or dosimetrist in achieving the best dose distribution; have sufficient knowledge to select the best possible combination of dose and fractionation for a given site and volume; be competent to judge the quality of the dose distribution and the technical feasibility and accuracy of proposed plan; and understand the capabilities and limitations of the staff and computer systems involved in the radiation treatment planning process. No computer software can correct the radiation oncologist's errors of clinical judgment, misunderstanding of physical concepts, or inadequate treatment delivery.

Tumor size, irradiation dose, and long-term outcome of carcinoma of uterine cervix

PURPOSE

To assess the impact of tumor size and extent, and dose of irradiation on pelvic tumor control, incidence of distant metastases, and disease-free survival in carcinoma of the uterine cervix.

METHODS AND MATERIALS

Records were reviewed of 1499 patients (Stages IA-IVA) treated with definitive irradiation (combination of external beam plus two intracavitary insertions to deliver doses of 65-95 Gy to point A, depending on stage and tumor volume). Follow-up was obtained in 98% of patients (median 11 years, minimum 3 years, maximum 30 years). The relationship between outcome and tumor size was analyzed in each stage. Pelvic tumor control was correlated with total doses to point A and to the lateral pelvic wall.

RESULTS

The 10-year actuarial pelvic failure rate in Stage IB was 5% for tumors <2 cm, 15% for 2.1-5 cm, and 35% for tumors >5 cm (p = 0.01); in Stage IIA, the rates were 0%, 28%, and 25%, respectively (p = 0.12). Stage IIB unilateral or bilateral nonbulky tumors <5 cm had a 23% pelvic failure rate compared with 34% for unilateral or bilateral bulky tumors >5 cm (p = 0.13). In Stage IIB, pelvic failures were 18% with medial parametrial involvement only, compared with 28% when tumor extended into the lateral parametrium (p = 0.05). In Stage III, unilateral parametrial involvement was associated with a 32% pelvic failure rate versus 50% for bilateral extension (p < 0.01). Ten-year disease-free survival rates were 90% for IB tumors <2 cm, 76% for 2.1-4 cm, 61% for 4.1-5 cm, and 47% for >5 cm (p = 0.01); in Stage IIA, the rates were 93%, 63%, 39%, and 59%, respectively (p < or = 0.01). Patients with Stage IIB medial parametrial involvement had better 10-year disease-free survival (67%) than those with lateral parametrial extension (56%) (p = 0.02). Stage III patients with unilateral tumor extension had a 48% 10-year disease-free survival rate compared with 32% for bilateral parametrial involvement (p < or = 0.01). The presence of endometrial extension or tumor only in the endometrial curettings had no significant impact on pelvic failure. However, in patients with Stage IB disease, the incidence of distant metastases was 31% with positive curettings, 15% with negative curettings, and 22% with admixture (p < or = 0.01). In Stage IIA, the corresponding values were 51%, 33%, and 18% (p = 0.05). The 10-year disease-free survival rates in Stage IB were 67% with positive curettings, 81% for negative curettings, and 77% for admixture (p = 0.02); in Stage IIA, the rates were 45%, 66%, and 67%, respectively (p = 0.14). Because this is not a prospective Phase II dose-escalation study, the correlation of doses of irradiation with pelvic tumor control in the various stages and tumor size groups is not consistent. Nevertheless, with Stage IB and IIA tumors <2 cm in diameter, the pelvic failure rate was under 10% with doses of 70-80 Gy to point A, whereas for larger lesions even doses of 85-90 Gy resulted in 25% to 37% pelvic failure rates. In Stage IIB with doses of 70 Gy to point A, the pelvic failure rate was about 50% compared with about 20% in nonbulky and 30% in bulky tumors with doses > 80 Gy. In Stage III unilateral lesions, the pelvic failure rate was about 50% with < or =70 Gy to point A versus 35% with higher doses, and in bilateral or bulky tumors it was 60% with doses <70 Gy and 50% with higher doses.

CONCLUSIONS

Clinical stage and size of tumor are critical factors in prognosis, therapy efficacy, and evaluation of results in carcinoma of the uterine cervix. The doses to point A suggest that for lesions <2 cm, doses of 75 Gy result in < or =10% pelvic failures, whereas in more extensive lesions, even with doses of 85 Gy, the pelvic failure rate is about 30%; and in Stage IIB-III tumors, doses of 85 Gy result in 35-50% pelvic failures. Refinements in brachytherapy techniques and/or use of agents to selectively sensitize the tumors to irradiation will be necessary to improve the present results in invasive carcinoma of t

The clinical implications of hydronephrosis and the level of ureteral obstruction in stage IIIB cervical cancer

PURPOSE

There are two criteria for the diagnosis of Stage IIIB cervical cancer in the FIGO staging system: tumor fixation to the pelvic side wall and/or the presence of hydronephrosis due to tumor. However, we often encounter hydronephrosis without tumor fixed to the pelvic side wall or the level of ureteral obstruction not corresponding to the main tumor mass in the pelvis. The clinical implication of these phenomena remains unclear. We investigated the Stage IIIB population treated at the Mallinckrodt Institute of Radiology and hypothesized that, if hydronephrosis presents without tumor fixation to the pelvic side wall or if the level of ureteral obstruction is above the main pelvic tumor mass, it most likely resulted from external compression of ureter(s) by enlarged lymph nodes and, consequently, a worse outcome is expected.

METHODS AND MATERIALS

From 1959 to 1989, there were 297 patients with Stage IIIB cervical cancer who received definitive radiation therapy at the Mallinckrodt Institute of Radiology and were assessable for the presence of hydronephrosis and the level of ureteral obstruction. There were 281 patients who presented with tumor fixed to the pelvic side wall, and 62 of them were associated with concurrent hydronephrosis. An additional 16 patients presented with hydronephrosis without tumor fixation to the pelvic side wall. Among these 78 documented cases of hydronephrosis, the level of ureteral obstruction was above the true pelvis in 39 patients, and below the true pelvis in the other 39. Radiation therapy was individualized according to tumor extension and configuration; para-aortic lymph nodes were not routinely treated except in patients with clinical evidence of nodal metastasis.

RESULTS

The progression-free survival (PFS) at 5 years was 35% in 62 patients with hydronephrosis and tumor fixed to the pelvic side wall vs. 43% in 213 patients with tumor fixed to the pelvic side wall only (p=0.12). However, PFS at 5 years decreased to 23% in 16 patients who presented with hydronephrosis without tumor fixation to the pelvic side wall (p < 0.001). When the level of ureteral obstruction was investigated, 5-year PFS was 39% vs. 22%, respectively, for the obstruction below vs. above the true pelvis (p=0.02). The majority of patients with ureteral obstruction above the true pelvis died of distant metastasis.

CONCLUSIONS

The additional presence of hydronephrosis did not significantly worsen the PFS among Stage IIIB patients with tumor fixation to the pelvic side wall. However, hydronephrosis without tumor extending to the pelvic side wall or the level of ureteral obstruction above the true pelvis was associated with poor outcome due to a significant increase in distant failure. We propose that this population be separated from current Stage IIIB classification.

Impact of surgical staging in evaluating the radiotherapeutic outcome in RTOG #77-06, a phase III study for T1BN0M0 (A2) and T2N0M0 (B) prostate carcinoma

PURPOSE

To evaluate survival and time to metastatic disease in patients treated for localized prostatic carcinoma in a Phase III radiotherapy (RT) protocol, Radiation Therapy Oncology Group (RTOG) 77-06. Patients with T18N0M0 (A2) or T2N0M0 (B) disease after lymphangiogram (LAG) or staging laparotomy (SL) were randomized between prophylactic radiation to the pelvic lymph nodes and prostatic bed vs. prostatic bed alone. The outcome of both treatment arms, as well as a comparison of the LAG group, to that of the SL group, are updated.

METHODS AND MATERIALS

A total of 449 eligible males were entered into RTOG protocol 7706 between 1978 and 1983. Lymph node staging was mandatory but at the physician's discretion; 117 (26%) patients had SL, while 332 (74%) had LAG. Follow-up was a median of 12 years and a maximum of 16 years. For those randomized to receive prophylactic pelvic lymph nodal irradiation, 45 Gy of megavoltage RT was delivered via multiple portals in 4.5-5 weeks, while all patients received 65 Gy in 6.5-8 weeks to the prostatic bed.

RESULTS

There was no significant difference in survival whether treatment was administered to the prostate or prostate and pelvic lymph nodes. The SL group had greater 12-year survival than the LAG group (48% vs. 38%, p = 0.02). Disease-free survival was statistically significant, with 38% for the SL group vs. 26% for the LAG group (p = 0.003). Bone metastasis was less common in the SL group (14%) than the LAG group (27%) (p = 0.003).

CONCLUSION

At 12-year median follow-up, there still was no survival difference in those patients treated prophylactically to the pelvic nodes and prostatic bed vs. the prostatic bed alone. Those patients not surgically staged with only LAG for lymph node evaluation were less accurately staged, as reflected by a statistically significant reduced survival and earlier metastases.

Physician resource utilization in radiation oncology: a model based on management of carcinoma of the prostate

PURPOSE

To develop a methodology to estimate the comparative cost of physician time in treating patients with localized prostate cancer, using as an example two-dimensional (2D) vs. three-dimensional (3D) conformal irradiation techniques, and to illustrate how current cost-accounting techniques can be used to quantify the cost of physician time and effort of any treatment.

METHODS AND MATERIALS

Activity-based costing, a recent innovation in accounting, widely recommended for estimating and managing the costs of specific activities, was used to derive physician resource utilization costs (actual cost of the physician services and related support services consumed).

RESULTS

Patients treated with 3D conformal irradiation consume about 50% more physician time than patients receiving 2D conventional radiation therapy. The average professional reimbursement for the 3D conformal irradiation is only about 26% more than for the 2D treatment. Substantial variations in cost are found depending on the total available physician working hours. In an academic institution, a physician working 40 hours a week would have to spend an average of about 60% of available time on clinical services to break even on a 2D treatment process and over 74% of available time on clinical work to break even on a 3D treatment process. The same physician working 50 hours a week would have to spend an average of about 48% of available time on 2D clinical services and about 60% of available time on 3D clinical work to break even. Current Medicare reimbursement for 3D treatment falls short of actual costs, even if physicians work 100% of a 50-hour week. Medicare reimbursement for 2D barely allows the department to break even for 2D treatments.

CONCLUSIONS

Costs based on estimates of resource use can be substantially under- or overestimated. A consistent language (method) is needed to obtain and describe the costs of radiation therapy. The methodology described here can help practitioners and researchers more accurately interpret actual cost information. Future use of such cost-estimation methodologies could provide consistent and comparable costs for negotiations with health care providers and help assess different treatment strategies.

Superficial hyperthermia and irradiation for recurrent breast carcinoma of the chest wall: prognostic factors in 196 tumors

PURPOSE

To correlate patient-, tumor-, and treatment-related factors with subsequent local tumor control.

METHODS AND MATERIALS

From 1977 to 1990, 196 subcutaneous/superficial lesions (179 measurable, 17 microscopic) in 151 patients with recurrent breast carcinoma of the chest wall were treated with superficial 915-MHz microwave hyperthermia and irradiation. The definition of min t43 > or = 10 min is that all monitored tumor catheters had a minimum of 1 hyperthermia session with temperatures > 43 degrees C for at least 10 min.

RESULTS

Factors correlating with local control on univariate analysis included length of survival (> or = 1 year vs. < 1 year) (p < 0.0001), specific absorption rate (SAR) (> or = 25% vs. < 25%) (p = 0.0001), minimum t43 > 10 min (p < 0.0001), tumor volume (p < 0.0001), tumor surface area (p < 0.0001), tumor depth (p = 0.0002), number of hyperthermia sessions (p = 0.0003), and current radiation dose (p = 0.0012). On multivariate analysis, the factors best correlated with ultimate local control were SAR (p < 0.001) and number of hyperthermia sessions (p = 0.003).

CONCLUSIONS

Multivariate analysis supports the importance of adequate specific absorption rate (SAR) coverage as a better predictor of local control than tumor volume, surface area, or depth. The explanation is that SAR can be correlated with the tumor surface area and depth, depending on the hyperthermia applicator characteristics. It is recommended that future clinical trials stratify study lesions into either SAR > or = 25% or < 25% because this can be readily estimated prior to initiating treatment. It is also recommended that future clinical trials attempt to have adequate lengths of follow-up after therapy to assess the results in long-term survivors.

Uterosacral space involvement in locally advanced carcinoma of the uterine cervix

PURPOSE

Radiation therapy is the standard management for locally advanced cervical cancer, but it has not yielded fully satisfactory results; a relatively high incidence of local failure remains. Standard radiation therapy techniques combine external beam radiation and brachytherapy generating a homogeneously composite dose distribution covering the lateral parametria but may not be adequate in the uterosacral and perirectal areas due to the spatial arrangement of intracavitary system and the constraints of rectal tolerance. We hypothesize that these dosimetric characteristics might lead to a higher incidence of central/marginal failures when the uterosacral space is involved by locally advanced carcinoma of uterine cervix.

METHODS AND MATERIALS

Between January 1970 and December 1989, 343 patients with clinical Stage IIIB cervical cancer were treated at the Mallinckrodt Institute of Radiology with radiation therapy alone. We identified 83 patients with clinical evidence of tumor in the uterosacral region; the remaining 260 patients either did not have uterosacral involvement or were unspecified. The dose of external beam irradiation ranged from 18.02 to 33.20 Gy to the central pelvis and 48.22 to 59.40 Gy to the lateral parametrium. The average total dose, including brachytherapy contribution, to point A and the lateral pelvis was 80.30 to 86.46 Gy and 60.50 to 73.40 Gy, respectively. External beam dose to the lateral parametria was, on average, 10 Gy higher in patients with uterosacral involvement.

RESULTS

We categorized the patterns of pelvic failure into central/marginal (including medial parametrium) and lateral parametria. The cumulative incidence of central/marginal failure at 5 years was significantly higher in the group of patients with uterosacral involvement (36% compared with 21% for patients without uterosacral involvement or unspecified) (p = 0.002). Lateral parametrial failure was similar for patients with and without uterosacral involvement (39% and 38% at 5 years, respectively) (p = 0.42). The actuarial incidence of distant metastasis was identical in the two groups: 46% at 5 years. Multivariate analysis confirmed that uterosacral space involvement increased the risk of pelvic recurrence (p = 0.044) and was the most significant factor that influenced the central/marginal pelvic failure (p = 0.002).

CONCLUSIONS

Uterosacral involvement by locally advanced carcinoma of the uterine cervix significantly increased overall pelvic failure and was the most significant prognosticator of central/marginal pelvic failure. This is the result of the spatial constraints of the standard intracavitary geometry that deliver inadequate dose posteriorly to encompass the uterosacral space. Plausible ways to compensate the underdose in the uterosacral space include increasing whole pelvis dose without compromising the intracavitary brachytherapy dose, using a supplemental interstitial implant or adding a posterior oblique external beam boost.

Cost benefit of emerging technology in localized carcinoma of the prostate

PURPOSE

In a health care environment strongly concerned with cost containment, cost-benefit studies of new technology must include analyses of loco-regional tumor control, morbidity, impact on quality of life, and financial considerations.

METHODS AND MATERIALS

This nonrandomized study analyzes 124 patients treated with three-dimensional conformal radiation therapy (3D CRT) and 153 with standard irradiation (SRT) between January 1992 and December 1995, for histologically proven adenocarcinoma of prostate, clinical Stage T1 or T2. Mean follow-up is 1.4 years. Three-dimensional CRT consisted of six or seven coplanar oblique and lateral and, in some patients, AP fields designed to treat the prostate with a 1 to 1.7 cm margin. SRT consisted of 120 degrees bilateral arc rotation. Total doses to prostate were 67 to 70 Gy when pelvic lymph nodes were irradiated or 68.4 to 73.8 Gy when prostatic volume only was treated; dose per fraction was 1.8 Gy. Patients were interviewed weekly for severity of 12 acute intestinal and urinary pelvic irradiation side effects (0 to 4+ grading). Time and effort for 3D RTP and daily treatment with 3D CRT and SRT were recorded. Dose-volume histograms (DVHs) were calculated for gross tumor volume, planning target volume, bladder, and rectum. Actual reimbursement to the hospital and university was determined for 41 3D CRT, 43 SRT, and 40 radical prostatectomy patients treated during the same period.

RESULTS

Average treatment planning times (in minutes) were: 101 for 3D conformal therapy simulation, 66 for contouring of target volume and sensitive structures, 55 for virtual simulation, 39 for plan preparation and documentation, 65 for physical simulation, and 20 for approval of treatment plan. Daily mean treatment times were 19 min for 3D CRT with Cerrobend blocking, 16 with multileaf collimation, and 10 with bilateral arc rotation. Dosimetric analysis (DVHs) showed a reduction of 50% in volume of bladder or rectum receiving doses higher than 65 Gy. Acute side effects included dysuria, moderate difficulty in urinating, and nocturia in 25-39% of both SRT and CRT patients; loose stools or diarrhea in 5-12% of 3D CRT and 16-22% of SRT patients; moderate proctitis in 3% of 3D CRT and 12% of SRT patients (p = 0.01). Chemical disease-free survival (prostate-specific antigen < or =2 ng/ml) at 3 years was 90% with 3D CRT and 80% with SRT (p = 0.01). Average initial treatment reimbursements were $13,823 (3D CRT), $10,864 (SRT), and $12,250 (radical prostatectomy). Average total treatment reimbursement and projected cost of management of initial therapy failures per patients were $15,173, $16,264, and $16,405, respectively.

CONCLUSIONS

Three-dimensional CRT irradiated less bladder and rectum volume than SRT; CRT initial reimbursement was 28% higher than SRT and 12% higher than radical prostatectomy. Because of projected better local tumor control, average total cost of treating a patient with 3D CRT or radical prostatectomy is equivalent to cost of SRT. Treatment morbidity was lower with 3D CRT. Our findings reflect an overall benefit with 3D CRT as a new promising technology in treatment of localized prostate cancer. Dose-escalation studies may enhance its efficacy and cost benefit.

Clinical-severity staging system for oropharyngeal cancer: five-year survival rates

OBJECTIVE

To improve the classification and survival estimates for patients with oropharyngeal cancer by combining cancer symptom severity and comorbidity with the current TNM cancer staging system.

DESIGN

Retrospective medical record review using explicit coding criteria.

SETTING

University medical center.

PATIENTS AND METHODS

Two hundred ninety-six patients receiving initial treatment from January 1, 1980, to December 31, 1989. Multivariate analysis identified patient factors that had a significant impact on 5-year survival. These patient factors, symptom severity and comorbidity, were combined with cancer stage to create a composite clinical-severity staging system.

MAIN OUTCOME MEASURE

Five-year survival.

RESULTS

The overall 5-year survival rate was 38% (111/ 296). Survival by TNM cancer stage was 67% (18/27) for stage I, 46% (24/52) for stage II, 31% (26/85) for stage III, and 32% (43/132) for stage IV (chi2=10.84; P=.001). When patients were grouped according to the clinical-severity staging system, survival rates were 70% (16 of 23) for stage A, 47% (71 of 152) for stage B, 27% (18 of 67) for stage C, and 11% (6 of 54) for stage D (chi2=34.49; P=.001).

CONCLUSIONS

Survival estimates can be improved by adding carefully studied and suitably defined patient variables to the TNM cancer stage. The current TNM cancer staging system for oropharyngeal cancer is based solely on the morphologic description of the tumor and disregards the clinical condition of the patient. Cancer symptom severity and comorbidity have a significant impact on survival. Continued exclusion of patient factors leads to imprecision in prognostic estimates and hinders interpretation of clinical studies.

Adenocarcinoma of the prostate: innovations in management

Adenocarcinoma of the prostate (CaP) in the Western world has become the most common noncutaneous human tumor. CaP is also the second most important cause of cancer deaths among the male population in the United States. Major progress was made in the past decade in better understanding this disease process, as well as in improved diagnostic accuracy. This improved diagnostic accuracy was due to wide application of prostate-specific antigen (PSA), use of transrectal ultrasound (TRUS), and greater awareness among clinicians of CaP. The use of PSA in clinical practice has resulted in a sharp increase in the number of patients diagnosed with capsule-confined tumors. The optimal treatment for capsule-confined CaP is in the process of being defined. Radical prostatectomy in the United States is currently the most commonly applied treatment for younger patients. Excellent treatment results with a 10-year actuarial survival > 80% are readily obtainable in properly selected patients. Nerve-sparing procedures helped reduce the high incidence of impotence that occurs in patients after radical retropubic prostatectomy. Radiotherapy remains the other curative treatment method in the management of CaP patients, with long-term survival rates similar to those reported in surgical series. Due to the problem of frequent preoperative tumor understaging, a routine use of postoperative irradiation to the prostatic fossa produces an excellent (> 95%) incidence of local tumor control. Management of patients with metastatic disease has undergone a considerable evolution with the development of modern hormonal management and treatment with strontium-89 to control intractable bone pain. Newer treatment methods such as hyperthermia are currently being investigated. Major efforts are directed toward the reduction of short- and long-term treatment toxicity associated with surgery, radiotherapy, and hormonal management, thus improving patient quality of life.

Nonrandomized evaluation of pelvic lymph node irradiation in localized carcinoma of the prostate

PURPOSE

A great deal of controversy exists regarding the potential benefit of pelvic lymph node irradiation compared with treatment to the prostate only in patients with localized prostate cancer. Despite numerous reports, including a randomized study, this issue has not been completely elucidated.

METHODS AND MATERIALS

A total of 963 patients with histologically proven localized adenocarcinoma of the prostate treated with definitive radiation therapy alone were analyzed. Median follow-up was 6.5 years (minimum: 2 years, maximum: 22 years). Pelvic lymph nodes received 40 to 55 Gy with anteroposterior/posteroanterior and sometimes lateral stationary portals in 1.8 Gy daily fractions; an additional dose was delivered to the prostate with 120 degrees bilateral are rotation to complete doses of 65 to 68 Gy for Stage A2 and B tumors and 68 to 71 Gy for Stage C tumors. The same total doses were delivered with smaller fields when the prostate only was treated.

RESULTS

In Stage A2 (T1b,c) the 10-year clinical pelvic failure rate was 16% regardless of the volume irradiated or tumor differentiation. With Stage B (T2) well- or moderately differentiated tumors, the 10-year pelvic failure rates were 22% when pelvic lymph nodes were irradiated and 32% when prostate only was irradiated (p = 0.41). With Stage A2 (T1b,c) and B (T2) poorly differentiated tumors, the 10-year pelvic failure rates were 32% and 7%, respectively (p = 0.72). With clinical stage C (T3) well-differentiated tumors treated with 50 to 55 Gy to pelvic lymph nodes, the pelvic failure rate was 22% compared with 37% in those receiving 40 to 45 Gy (p < or = 0.07). A significant reduction in pelvic failures was noted with Stage C poorly differentiated tumors when the pelvic lymph nodes received doses higher than 50 Gy (23%) compared with lower doses (46%) (p < or = 0.01). Volume or doses of irradiation did not influence incidence of distant metastases in any stage or tumor differentiation group. Disease-free survival did not correlate with volume treated in any clinical stage or tumor differentiation group. In 317 patients on whom pretreatment prostate-specific antigen levels were available, there is a suggestion that those treated to the pelvic lymph nodes had a higher chemical disease-free survival than those receiving prostate irradiation only. Follow-up is short, and differences are not statistically significant in any of the groups. Morbidity of therapy was slightly higher in patients treated to the pelvic lymph nodes, but in Stages A2 (T1b,c) and B (T2) differences are not statistically significant (4 to 6%). Stage C patients treated to the pelvic lymph nodes with 50 Gy had a 12% incidence of Grade 2 rectosigmoid morbidity compared with 6% in those treated with 40 Gy (p = 0.26).

CONCLUSIONS

In this retrospective analysis, pelvic lymph node irradiation did not influence local/pelvic tumor control, incidence of distant metastases, or disease-free survival in patients with clinical Stage A2 (T1b,c) or B (T2) localized carcinoma of the prostate. In patients with Stage C (T3) disease, irradiation of the pelvic lymph nodes with doses of 50 to 55 Gy resulted in a lower incidence of pelvic recurrences and improved disease-free survival. Morbidity of therapy was acceptable, although patients with Stage C disease had a somewhat higher incidence of Grade 2 rectosigmoid morbidity. Pelvic lymph node irradiation is being elucidated in properly designed prospective, randomized protocols.

Quality assurance in radiation oncology in the United States

We review the various components of quality assurance (QA), including the role of a QA committee, stressing its interdisciplinary nature relative to radiation oncologists, medical physicists, dosimetrists, and radiation therapy technologists. Current standard of QA are reviewed for treatment machines, dosimetry instrumentation, treatment planning, treatment planning computer systems, brachytherapy, and external beam therapy. The latter area includes discussions on the importance of a peer review new patient planning conference, chart checking and film review.

Phase III study of interstitial thermoradiotherapy compared with interstitial radiotherapy alone in the treatment of recurrent or persistent human tumors. A prospectively controlled randomized study by the Radiation Therapy Group

PURPOSE

The objectives of this randomized trial were to determine if interstitial thermoradiotherapy (ITRT) improves tumor regression/control in accessible lesions in comparison with interstitial radiotherapy (IRT) alone and to assess the skin and soft tissue complications with either modality.

METHODS AND MATERIALS

From January 1986 to June 1992, 184 patients with persistent or recurrent tumors after previous radiotherapy and/or surgery, which were amenable to interstitial radiotherapy, were accessioned to a protocol developed by the Radiation Therapy Oncology Group (RTOG). One hundred seventy-three cases were analyzed (87 patients in the IRT group and 86 in the ITRT arm). The two arms were well balanced regarding stratification criteria. Most tumors were in the head and neck (40% in the IRT group and 46% in the ITRT group), and pelvis (42% and 43%, respectively). Eighty-four percent of patients in both arms had prior radiation therapy (> or = 40 Gy); 50% and 40%, respectively, had prior surgery, and 34% in each arm had prior chemotherapy. The dose of radiation therapy administered was dependent on the previous radiation dose and did not exceed a total cumulative dose of 100 Gy. Hyperthermia was delivered in one or two sessions, either before or before and after interstitial implant. The intended goal of the hyperthermia was to maintain a minimal tumor temperature of 42.5 degrees C for 30 to 60 min.

RESULTS

There was no difference in any of the study end points between the two arms. Complete response (CR) was 53% and 55% in both arms. Two-year survival was 34% and 35%, respectively. Complete response rate for persistent lesions was 69% and 63% in the two treatment arms as compared with 40% and 48% for recurrent lesions. A set of minimal adequacy criteria for the delivery of hyperthermia was developed. When these criteria were applied, only one patient had an adequate hyperthermia session. Acute Grade 3 and 4 toxicities were 12% for IRT and 22 % for ITRT. Late Grade 3 and 4 toxicities were 15% for IRT and 20% for ITRT. The difference was not significant.

CONCLUSIONS

Interstitial hyperthermia, as applied in this randomized study, did not show any additional beneficial effects over interstitial radiotherapy alone. Delivery of hyperthermia remains a major obstacle (since only one patient met the basic minimum adequacy criteria as defined in this study). The benefit of hyperthermia in addition to radiation therapy still remains to be proven in properly randomized prospective clinical trials after substantial technical improvements in heat delivery and dosimetry are achieved.

Brachytherapy or electron beam boost in conservation therapy of carcinoma of the breast: a nonrandomized comparison

PURPOSE

The results of breast-conservation therapy using breast irradiation and a boost to the tumor excision site with either electron beam or interstitial 192Ir implant are reviewed.

METHODS AND MATERIALS

A total of 701 patients with histologically confirmed Stage T1 and T2 carcinoma of the breast were treated with wide local tumor excision or quadrantectomy and breast irradiation. The breast was treated with tangential fields using 4 or 6 MV photons to deliver 48 to 50 Gy in 1.8 to 2 Gy daily dose, in five weekly fractions. In 80 patients the regional lymphatics were irradiated. In 342 patients with Stage T1 and 107 with Stage T2 tumors, boost to the primary tumor excision site was delivered with 9 MeV and, more frequently, with 12 MeV electrons. In 91 patients with Stage T1 and 38 patients with Stage T2 tumors an interstitial 192Ir implant was performed. Tumor control, disease-free survival, cosmesis, and morbidity of therapy are reviewed. Minimum follow-up is 4 years (median 5.6 years; maximum, 24 years).

RESULTS

The overall local tumor recurrence rates were 5% in the T1 and 11% in the T2 tumor groups. There was no significant difference in the breast relapse rate in patients treated with either electron beam or interstitial 192Ir boost. Regional lymph node recurrences were 1% in patients with T1 and 5% with T2 tumors. Distant metastases were recorded in 5% of the T1 and 23% of the T2 groups. The 10-year actuarial disease-free survival rates were 87% for patients with T1 and 75% with T2 tumors. Disease-free survival was exactly the same in patients receiving either electron beam or interstitial 192Ir boost. Cosmesis was rated as excellent/good in 84% of patients with T1 tumors treated with electron beam and 81% of patients treated with interstitial implant, and 74 and 79% respectively, in patients with T2 tumors.

CONCLUSIONS

Breast-conservation therapy is an effective treatment for patients with T1 and T2 carcinoma of the breast. There is no difference in local tumor control, disease-free survival, cosmesis, or morbidity in patients treated with either electron beam or interstitial 192Ir implant boost. Clinical trials in progress will further elucidate this controversial subject.

Prospective phase I/II studies of definitive irradiation and chemotherapy for advanced gynecologic malignancies

PURPOSE

This is a prospective study to evaluate toxicity and efficacy of concurrent irradiation and three cycles of chemotherapy bolus cisplatin and infusion 5-fluorouracil (5FU) in patients with advanced gynecologic malignancies.

MATERIALS AND METHODS

Patients received cisplatin, 50 mg/m2 I.V. rapid infusion, and 5-day continuous infusion of 5FU (750 mg/m2 per day (schedule A); or cisplatin 75 mg/m2 i.v. rapid infusion, and 4-day continuous infusion of 5FU 1,000 mg/m2 per day (schedule B). Schedule A was given to 25 patients in the first 36 months of the study and was changed to schedule B in an additional 42 patients. All patients received irradiation, which usually consisted of 20 Gy whole pelvis, 30-40 Gy split field, and two intracavitary insertions for a total of 80-90 Gy to point A. Primary cervical cancer occurred in 40 patients with 3 having stage IB bulky, 2 with stage IIA, 5 with stage IIB, 2 with stage IIIA, 23 with stage IIIB, 4 with stage IV, and 1 with stage IVB. Recurrent cervical carcinoma after radical hysterectomy occurred in 18 patients. The remainder of the patients consisted of two each with stages III and IV endometrial carcinoma, two with stage III vaginal carcinoma, two with stage III vulvar carcinoma, and one with recurrent vulvar carcinoma. Patients were treated from 1985 through 1992.

RESULTS

The 5-year overall survivals for patients with stages IB (bulky)-IIB cervical cancer was 70%, 25% for stages IIIA-IVA, and 39% for patients with recurrent cervical carcinoma. All four patients with endometrial carcinoma have recurred and died. Two patients with vulvar carcinoma are alive and free of disease, and one is dead of intercurrent disease. One patient with stage III vaginal carcinoma is alive and free of disease, while the other recurred and died. No significant differences were observed in the toxicity of the two chemotherapy schedules. There were 9/39 (23%) grade 4 and one fatal complication in those with primary cervical carcinoma. The overall fistulae rate was 11% (4/39) with three patients developing rectovaginal fistulae and one having vesicovaginal fistula.

CONCLUSION

Concurrent chemotherapy and irradiation for advanced gynecologic malignancies as administered in this study is highly toxic and fails to demonstrate an obvious survival improvement.

Carcinoma of the uterine cervix. II. Lack of impact of prolongation of overall treatment time on morbidity of radiation therapy

PURPOSE

Several reports document a negative impact of prolongation of overall treatment time in a course of irradiation on tumor control and survival. A correlation has been documented of incidence of significant treatment sequelae with increasing doses of irradiation, volume of the specific organ, and dose per fraction. However, no data were found on the potential correlation of overall irradiation treatment time with significant sequelae.

METHODS AND MATERIALS

Records were reviewed of 1,269 patients with carcinoma of the cervix (Stage IB to HI) treated with definitive irradiation (combination of external beam and two intracavitary insertions). Follow-up was obtained in 97% of patients (median, 12 years; minimum, 3 years; maximum, 28 years). The relationships between overall treatment time and time of brachytherapy and incidence of treatment sequelae were analyzed for each stage.

RESULTS

Overall incidence of Grades 2 (moderate) sequelae was 7% and of Grade 3 (severe) sequelae, 11%. There was no significant correlation of various incidences of Grade 2 and 3 sequelae with overall treatment times (8% in patients treated in less than 7 weeks, 9% in 7.1 to 9 weeks, and 12% when treatment time was longer than 9 weeks) (p = 0.08). In patients with Stage IB and IIA tumors, incidence of rectal toxicity (mostly proctitis) was comparable in patients treated in less than 7 or 7.1 to 9 weeks (4.1 and 6%, respectively) and slightly higher in those treated in longer periods (11.5%) (p = 0.24). In patients with Stage IIB and III, the incidence of Grade 2 and 3 small bowel morbidity was 2% in those treated in less than 7 weeks, 6% for 7.1 to 9 weeks, and 4.9% for longer times (p < or = 0.01). This increased morbidity was also correlated with total dose of irradiation to the lateral pelvic wall: 5 of 257 (2%) for less than 60 Gy and 21 of 438 (4.8%) for higher doses (p < or = 0.01). There was no significant correlation between the timing of brachytherapy (usually two low dose rate intracavitary insertions performed within 4.5 to 6.5 weeks of initiation of external beam therapy) and significant treatment sequelae.

CONCLUSIONS

We observed a varied average incidence of Grade 2 and 3 morbidity in the bladder, rectum, and small intestine with different overall treatment times, without a definite pattern to suggest an impact of prolongation of treatment time on morbidity. Likewise, there was no significant correlation with the timing of intracavitary insertions and morbidity of therapy. Because prolongation of the overall treatment time has a well-documented detrimental effect on pelvic tumor control and survival in carcinoma of the cervix with no significant impact on morbidity, it is imperative to deliver radiation therapy in the shortest possible time and without schedule interruptions.

Medically inoperable stage I endometrial carcinoma: a few dilemmas in radiotherapeutic management

PURPOSE

The aggressiveness of radiation therapy for patients with medically inoperable endometrial carcinoma is controversial. Patients may die of their underlining medical disease before succumbing to cancer. We try to identify certain subgroup of patients who might benefit most from an aggressive approach and also investigate the impact of residual tumor present in dilatation and curettage (D&C) specimen obtained in second intracavitary implant (ICI).

METHODS AND MATERIALS

From 1965 to 1990, 101 patients were treated for clinical clinical Stage I endometrial carcinoma with RT alone due to medical problems. Ages ranged from 39 to 94 years (median 71 years). There were 18 patients with clinical Stage IA and 83 with clinical Stage IB disease. Histology included 44 well-differentiated, 37 moderately differentiated, and 20 poorly differentiated tumors. Radiation therapy consisted of external beam only in 3 patients, ICI alone in 26, whole pelvis plus ICI in 10, and whole pelvis plus split field plus ICI in 62. A second D&C was performed on 26 patients at the time of the second ICI. Minimum follow-up was 2 years (median, 6.3 years).

RESULTS

The 5-year actuarial disease-free survival (DFS) for the studied cohort is comparable to the expected survival of an age-matched population. Pelvic control was 100% for Stage IA and 88% for Stage IB with 5-year disease-free survivals of 80 and 84%, respectively. We also observed a greater disassociation of DFS and overall survial among patients older than 75 years (84 and 55%, respectively) than in younger patients (84 and 78%, respectively). This is mainly because older patients succumbed to their medical illness. Well-differentiated disease demonstrated the trend toward a better outcome than moderately or poorly differentiated lesions in Stage IB patients (p = 0.05), but not in Stage IA patients. Aggressive radiation therapy approach showed the trend toward a better result in Stage IB patients 75 years of age or younger. There were two failures among 19 patients with no tumor found in the D&C specimen at the time of second implant. In contrast, seven patients with residual tumor seen in the endometrial sample at the time of second implant remain disease free.

CONCLUSIONS

Radiation therapy alone is an effective treatment modality for medically inoperable Stage I endometrial carcinoma. Disease-free survival can be translated into longer overall survival in the younger age group, but not in older patients. The latter tend to die of their underlining medical illness. Tumor differentiation influenced the prognosis of Stage IB disease. No tumor seen in the endometrial sampling at the time of second implant did not correlate with a better disease control, and the treatment plan should not be modified on such information.

Radiation therapy in the treatment of localized prostate cancer: an alternative to an emerging consensus

Optimal treatment for patients with localized carcinoma of prostate is controversial. Radiation therapy is an established modality; reports indicate that results are comparable to those of radical prostatectomy. A retrospective review was carried out of 963 patients with carcinoma of the prostate treated with definitive irradiation (65 to 71 Gy in 6.5 to 7 weeks). Survival, incidence of local recurrence and distant metastases, and postirradiation PSA data were analyzed. Ten-year disease-free survival with external irradiation was 100% for clinical stage A1 (T1a), 69% for stage A2 (T1b,c), 57% for clinical stage B (T2), and 41% for stage C (T3). Initial PSA level closely correlated with probability of freedom from chemical failure (PSA elevation) after definitive irradiation in 317 patients with stage T1b,c and T2 tumors (96% and 89%, respectively, with initial PSA of < 10 ng/ml and 75% and 65% with higher PSA levels). Although modern irradiation techniques produce results comparable to those of radical prostatectomy in localized prostate carcinoma, we must continue to critically assess treatment policies, develop appropriately designed prospective clinical trials, and define optimal management of these patients.