Conventional four-field pelvic radiotherapy technique without CT treatment planning in cancer of the cervix: potential geographic miss

Conventional radiotherapy planning of cervical cancer in resource-constrained set-up: Utilizing soldering lead wire to delineate radiotherapy portal

•

Cervical cancer is the commonest malignancy among women in developing countries.

•

Radiotherapy is mainstay of management and simulator for RT planning may be sparse.

•

Our study has demonstrated the utility of locally available resources for simulation.

•

Using soldering wire for conventional RT field delineation appears to be feasible.

•

Future studies are needed to validate the RT portals delineated by this technique.

Simulator for radiotherapy planning may not be available in resource-constrained set-up. Surface anatomy based planning has its own limitation in terms of adequately covering target due to variation of anatomy and tumor growth and spread pattern. Hence, improvisation of radiotherapy planning of cervical cancer, commonest malignancy among women in this set-up, utilizing locally available resource may improve treatment quality.

Soldering lead wire, plumber’s measuring tape, diagnostic x-ray and transpore adhesive tape were utilized to delineate radiotherapy portals for management of cervical cancer. Delineation of radiotherapy portals for irradiation of different regions in selected patients of carcinoma cervix is feasible in resource-constrained set-up. Radiotherapy delivery by conventional 2-D technique through the portal designed by utilizing soldering lead wire and diagnostic x-ray was achievable. Radiotherapy portal so delineated need to be validated in future clinical studies.

Better survival with three-dimensional conformal radiotherapy than with conventional radiotherapy for cervical cancer: a population-based study

Three-dimensional conformal radiation therapy (3DCRT) has emerged as a preferred treatment for gynecologic malignancies. Yet its superiority to conventional radiotherapy (2-dimensional radiotherapy (2DRT)) for gynecologic malignancies has not been well established. Data from the 2005 to 2010 National Health Insurance Research Database (NHIRD) provided by the National Research Institutes in Taiwan were analyzed to address this issue. Patients were initially diagnosed as having cervical cancer according to the International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) code 180, and this clinical diagnosis was confirmed histopathologically or cytologically. Kaplan-Meier method and Cox proportional hazards regression were used to analyze the reported data. Between January 2005 and December 2010, there were 776 patients with newly diagnosed cervical cancer without metastasis, local recurrence, or surgical treatment before RT and 132 and 644 patients, respectively, who received 2DRT and 3DCRT. After adjustment for age, diabetes mellitus, hypertension, coronary heart disease, hyperlipidemia, side effects, urbanization level, geographic region, and enrollee category in the 5-year follow-up period, the HR was 1.82 (95% CI, 1.16–2.85, P = 0.009). The 5-year survival rate in the 2DRT and 3DCRT groups was 73.0% and 82.3%, P = 0.007, respectively. Cervical cancer patients treated with 3DCRT had better overall survival.

Movement of the cervix in after-loading brachytherapy: implications for designing external-beam radiotherapy boost fields

AIMS

Women with invasive carcinoma of the cervix treated by chemo-radiotherapy and brachytherapy may also receive a pelvic sidewall boost using a midline shield (MLS). The purpose of this study was to assess the usefulness of implanted gold grains in detecting the movement of the cervix caused by the insertion of low-dose-rate brachytherapy applicators, and its implications in designing the MLS.

MATERIALS AND METHODS

The medical records of 42 women with various stages of cervical carcinoma, who were treated by radical chemo-radiotherapy, were reviewed. All of these women underwent examination under anaesthesia (EUA) and a gold-grain insertion to demarcate the vaginal tumour extent, in the antero-posterior and lateral planes, before starting external-beam radiotherapy. The isocentric orthogonal films (simulator films) of external radiotherapy and brachytherapy were compared to assess the change in position of the gold grains and the consequences for the design of the MLS for parametrial and pelvic sidewall boosts.

RESULTS

A significant shift in the position of the gold grains was noted in both the x (lateral) and the y (cranial/caudal) axes. The median shift of the midline, right and left lateral gold grains was 4.5, 5 and 7 mm in the x axis, whereas it was 10, 8 and 9.5 mm in the y axis, respectively. The median shift in the x and y axes was 5.5 and 9 mm, ranging from 1 to 40 mm and 1 to 45 mm, respectively. The gold grains were shifted cranially in 34 (80%) and laterally in 29 (69%) women. Thirty-two women (76.2%) received parametrial boost radiotherapy, of which 25 (59.5%) women had a customised, pear-shaped shield, and the remaining seven (16.7%) had a straight-sided, rectangular MLS. Four women (9.5%) relapsed locally, and three of them had been treated using a customised shield. In two of these four women, there was an absolute under-dosage of the central pelvis at the tip of the intra-uterine tube by 50% of the parametrial boost dose (5.4 Gy/3 fractions/3 days).

CONCLUSIONS

Insertion of the gold grains during pre-treatment EUA is a useful technique in detecting the movement of the cervix. A significant shift in the position of the gold grains was noted in both the x (lateral) and the y (cranial/caudal) axes. These shifts in the cervix can result in under-dosage of the central pelvis when delivering parametrial boosts with the MLS in place on the basis of the brachytherapy check films. When designing the individualised MLS, the resulting under-dosage could be avoided by taking account of the shift in the gold grain markers and allow the delivery of a more homogenous dose to the pelvis.

Conventional 4-field box radiotherapy technique for cancer cervix: potential for geographic miss without CECT scan-based planning

BACKGROUND

The advantage of 4-field radiation to the pelvis is that the use of lateral portals spares a portion of the small bowel anteriorly and rectum posteriorly. The standard lateral portals defined in textbooks are not always adequate especially in advanced cancer cervix.

METHODS

An analysis was done to determine adequacy of margins of standard lateral pelvic portals with CECT defined tumor volumes. The study included 40 patients of FIGO stage IIB and IIIB treated definitively for cancer cervix between 1998 and 2000. An inadequate margin was defined if the cervical growth and uterus were not encompassed by the 95% isodose.

RESULTS

An inadequate posterior margin was common with bulky disease (P = 0.06) and with retroverted uterus (P = 0.08). Menopausal status, FIGO stage, associated myoma, and age were of no apparent prognostic significance. Bulk retained significant on multivariate analysis. An inadequate anterior margin was common in premenopausal (P = 0.01); anteverted uterus (P = 0.02); associated myoma (P = 0.01); and younger patients (P = 0.03). It was not influenced by bulk or stage. Menopausal status and associated myoma retained significant on multivariate analysis.

CONCLUSION

Without the knowledge of precise tumor volume, the 4-field technique with standard portals is potentially risky as it may under dose the tumor through lateral portals and the standard AP/ PA portals are a safer option.

Results of radiation therapy for uterine cervical cancer using high dose rate remote after loading system

In Japan, radiotherapy with high dose rate remote after loading system (HDR-RALS) for intracavitary brachytherapy is the standard treatment for more than 30 years. This report showed the usefulness of HDR-RALS for uterine cervical cancer. From 1980 through 1999, 442 patients with uterine cervical cancers (stage I: 66, stage II: 161, stage III: 165, stage IV: 50) were treated. Radiotherapy was performed both external teletherapy and HDR-RALS. Overall survival rate at 5 years was 60.2%. The 5-year actuarial incidence of all complications was 16.4%. The 5-year actuarial incidence of all complications in cases treated with the sum doses of whole pelvic irradiation (without central shield) and RALS up to 49 Gy, 50 to 59 Gy or larger doses were 7.5%, 11.0% and 25.2%, respectively. Radiation therapy using HDR-RALS was very effective. While the dose of whole pelvic irradiation was increased, the actuarial incidence of all complications was increased.

Operable Stages IB and II cervical carcinomas: a retrospective study comparing preoperative uterovaginal brachytherapy and postoperative radiotherapy

PURPOSE

To evaluate our data concerning prognostic factors and treatment toxicity in a series of operable cervical carcinomas.

METHODS AND MATERIALS

Between May 1972 and January 1994, 414 patients with cervical carcinoma, staged according to the 1995 FIGO staging system (286 Stage IB1, 38 Stage IB2, 56 Stage IIA, and 34 Stage IIB with 1/3 proximal parametrial involvement), underwent radical hysterectomy with (n = 380) or without (n = 34) bilateral pelvic lymph node dissection (N+: n = 68). Group I included 168 patients who received postoperative radiation therapy (RT): 64 patients had low-dose-rate vaginal brachytherapy with a median total dose (MTD) of 50 Gy; 93 patients had external beam pelvic RT (EBPRT) with an MTD of 45 Gy over 5 weeks, followed by low-dose-rate vaginal brachytherapy (MTD: 20 Gy); and 11 patients had EBPRT alone (MTD: 50 Gy over 6 weeks). Group II included 246 patients treated with preoperative low-dose-rate uterovaginal brachytherapy (MTD: 65 Gy); 32 of these 246 patients also received postoperative EBPRT (MTD: 45 Gy over 5 weeks) delivered to the parametria and pelvic nodes. Mean follow-up from the beginning of treatment was 106 months.

RESULTS

First events included isolated locoregional recurrences (35 patients), isolated distant metastases (27 patients), and locoregional recurrences with synchronous metastases (13 patients). The 10-year disease-free survival (DFS) rate was 88% for Stage IB1, 44% for Stage IB2, 65% for Stage IIA, and 48% for Stage IIB. Multivariate analysis showed that independent factors influencing the probability of DFS were as follows: cervical site (exocervical or endocervical vs. both endo- and exocervical, relative risk [RR]: 1.77, p = 0.047), vascular space invasion (no vs. yes, RR: 1.95, p = 0.041), age (>51 years vs. <or=51 years, RR: 1.90, p = 0.013), 1995 FIGO staging system (IB1 vs. IIA, RR: 2.95, p = 0.004; IB1 vs. IB2, RR: 3.49, p = 0.0009; and IB1 vs. IIB, RR: 4.54, p = 0.00002), and histologic pelvic lymph node involvement (N- vs. N+, RR: 2.94, p = 0.00009). The sequence of adjuvant RT did not influence the probability of DFS (Group I vs. Group II, p = 0.10). In Group II, after univariate analysis, DFS was significantly influenced by histologic residual cervical tumor in the hysterectomy specimen (yes vs. no: 71% vs. 93%, respectively, p < 10(-6)) and by the size of the residual tumor (<or=1 cm vs. >1 cm: 83% vs. 41%, respectively, p = 0.001). The overall postoperative complication rate was 10% in Group I and 9% in Group II (p = 0.7). The rate of postoperative ureteral complications requiring surgical intervention was lower in Group I than in Group II (0.6% vs. 2.3%, respectively, p = 0.03). The overall 10-year rate for Grade 3 and 4 late radiation complications was 10.4%. Postoperative EBPRT significantly increased the 10-year rate for Grade 3 and 4 late radiation complications (yes vs. no: 22% vs. 7%, respectively, p = 0.0002).

CONCLUSION

The prognosis for patients with cervical carcinoma was not influenced by the sequence of adjuvant RT (preoperative uterovaginal brachytherapy vs. postoperative RT) for Stages IB, IIA, and IIB with 1/3 proximal parametrial involvement. However, postoperative EBPRT increased the risk of late radiation complications.

[Operable stage IB and II cancer of the uterine neck: retrospective comparison between preoperative utero-vaginal curietherapy and initial surgery followed by radiotherapy]

PURPOSE

To identify prognostic factors and treatment toxicity in a series of operable stages IB and II cervical carcinomas.

PATIENTS AND METHODS

Between May 1972 and January 1994, 414 patients (pts) with cervical carcinoma staged according to the 1995 FIGO staging system underwent radical hysterectomy with (n = 380) or without (n = 34) bilateral pelvic lymph node dissection. Lateral ovarian transposition to preserve ovarian function was performed on 12 pts. The methods of radiation therapy (RT) were not randomised and depended on the usual practices of the surgical teams. Group I: 168 pts received postoperative RT (64 pts received vaginal brachytherapy alone [mean total dose (MD): 50 Gy], 93 pts had external beam pelvis RT (EBPRT) [MD: 45 Gy over 5 weeks] followed by vaginal brachytherapy [MD: 20 Gy], and 11 pts had EBPRT alone [MD: 50 Gy over 6 weeks]. Group II: 246 pts received preoperative utero-vaginal brachytherapy [MD: 65 Gy], and 32 of theses 246 pts also received postoperative EBPRT [MD: 45 Gy over 5 weeks] delivered to the parametric and the pelvic lymph nodes with a midline pelvic shield. The mean follow-up was 106 months.

RESULTS

The 10-year disease-free survival (DFS) rate was 80%. From 75 recurrences, 35 were isolated locoregional. Multivariate analysis showed that independent factors decreasing the probability of DFS were: both exo and endocervical tumour site (p = 0.047), lymph-vascular space invasion (p = 0.041), age < or = 51 yr (p = 0.013), 1995 FIGO staging system (stage IB1 vs stage IIA, p = 0.004, stage IB1 vs stage IB2, p = 0.0009, and stage IB1 vs stage IIB with 1/3 proximal parametrical infiltration, p = 0.00002), and histological pelvic involved lymph nodes (p = 0.00009). Methods of adjuvant RT did not influence the probability of DFS (group I vs group II, p = 0.10). The postoperative complication rate was 10.2% in group I and 8.9% in group II (p = 0.7) but the postoperative urethral complication rate necessitating surgical intervention with reimplantation was lower in group I than in group II (0.6% vs 2.3%, respectively, p = 0.03). The 10-year rate for grade 3 and 4 late radiation complications according to the LENT-SOMA scoring system was 10.4%. EPRT significantly increased the 10-year rate for grade 3 and 4 late radiation complications (yes vs no: 22% vs 7%, respectively, p = 0.0002).

CONCLUSION

In our series, the methods of adjuvant RT (primary surgery vs preoperative uterovaginal brachytherapy) do not seem to influence the prognosis of the stage IB, IIA, and IIB (with 1/3 proximal parametrical involvement only) cervical carcinomas. The postoperative EPRT applied according to histopathological risk factors after surgical treatment increases the risk of late radiation complications.

[Epidermoid carcinoma of the uterine cervix at operable bulky stages IB and II treated with combined primary radiation therapy and surgery]

PURPOSE

To identify prognostic factors and treatment toxicity in a series of operable bulky stages I and II cervical carcinomas treated with a therapeutic modality combining primary irradiation and surgery.

PATIENTS AND METHODS

Between July 1982 and May 1996, 66 patients with bulky squamous-cell cervical carcinomas (stage IB2, IIA, and IIB with 1/3 proximal parametrial invasion) underwent primary external beam pelvic radiation therapy (37.40 Gy to 40 Gy over 4.5 weeks) and low-dose-rate uterovaginal brachytherapy (20 Gy) followed, 5 to 6 weeks later, by class II modified radical hysterectomy with bilateral pelvic lymphadenectomy. The four last patients received concomitant chemotherapy during the first and the fourth radiation week combining 5-FU and cisplatin. A clinical pelvic lymph node involvement had been observed in 7 patients. The clinical median tumor size was 5 cm in diameter (range: 4.5-8 cm). The median follow-up was 97 months.

RESULTS

Pathologic complete tumor response in specimen of hysterectomy were observed in 46 patients. Six patients had pathologic unilateral iliac lymph node involvement. The 5- and 10-year specific survival rates were 79 and 74%, respectively. The 5- and 10-year disease-free survival rates were 76% and 71%, respectively. The 10-year local control rate was 85%. The 10-year probability for pelvic recurrence was significantly influenced by the pathologic tumor response: 26% in the residual group vs 5% in the complete tumor response group, P = 0.024). After multivariate analysis, the independent factors decreasing the probability of disease-free survival were: pathologic pelvic lymph node involvement (P = 0.029), and parametrial invasion (P = 0.031). Five late severe complications requiring surgical intervention were observed: 2 bowel obstructions, 1 ureteral stenosis, 1 vesicovaginal fistula, and 1 radiation induced unilateral femoral necrosis.

CONCLUSION

A good local control is obtained after combined primary radiation therapy and surgery for bulky stages I and II cervical carcinomas. In our more recent practice, the treatment combines primary concomitant chemoradiation followed by surgery including pelvic and para-aortic lymphadenectomy.

[Gross tumor volume and clinical target volume in radiotherapy: tumors of the corpus uteri]

Surgery is the major treatment of the tumours of the corpus uteri. The imaging workup is essentially used to detect locally advanced lesions which are not suitable for surgery, because the preoperative knowledge of prognostic factors seldom influences treatment strategy in the early stages. The 3D planning of external irradiation for corpus uteri tumours is not very widespread, despite its real impact in preoperative irradiation strategy or irradiation alone. In postoperative strategy its importance is less evident; however, CT planning leads to a better knowledge of the dose distribution to the critical organs, which will probably contribute to a better control of late complications.

[Radiotherapy for tumors of the uterine cervix. Gross tumor volume and clinical target volume]

Treatment of carcinoma of the uterine cervix needs a multidisciplinary approach. External irradiation and brachytherapy are highly curative because of the tumor radiosensitivity. The main prognostic factors are tumoral volume and nodal involvement. Tumoral extent is evaluated by diagnostic MR imaging, and gynecological exam. Nodal involvement can be assessed, accurately by coelioscopic pelvic node sampling and by imaging modalities such as CT scan. The knowledge of these two factors helps to choose the treatment strategy. The use of imaging (MRI and CT) added to clinical findings allows to design external irradiation fields. 3D treatment planning in external irradiation and brachytherapy is based upon the use of imaging (CT and MRI). It leads to a better knowledge of dose distribution to the target and critical organs and allows more individualized and conformal treatment.

[Contribution of imaging in radiotherapy planning in uterine cervix cancers]

External irradiation and brachytherapy are curative in the treatment of carcinoma of the cervix. The aim of radiotherapy is to optimize the irradiation of the target volume and to reduce the dose to critical organs. The use of imaging (computed tomography and magnetic resonance imaging added to clinical findings and standard guidelines) are studied in the treatment planning of external irradiation and brachytherapy in carcinoma of the cervix. Imaging allows an individualized and conformal treatment planning.

A survey on staging and treatment in uterine cervical carcinoma in the Radiotherapy Cooperative Group of the European Organization for Research and Treatment of Cancer

BACKGROUND

The treatment outcome of advanced stage uterine cervical carcinoma remains unsatisfactory. In order to elaborate a novel trial within The Radiotherapy Cooperative Group (RCG) of the European Organization for Research and Treatment of Cancer (EORTC), we conducted a survey in 1997-1998 to determine the variability of pre-treatment assessment and treatment options. The variability of choosing surgery, defined radiation therapy techniques and chemotherapy are investigated, as well as the center's choices of future treatment strategies.

METHODS

Fifty two of 81 RCG centers from the RCG have participated in the survey. As one would expect, there is a large variation in the techniques used for pretreatment evaluation and treatment options. There is no 'standard' for reporting acute and late side effects. Chemotherapy is used neither systematically nor uniformly, and some centers continue to use neadjuvant chemotherapy modalities.

RESULTS

Furthermore, the survey reveals that there is a strong demand for the reduction of overall treatment-time, for clinical investigation of novel combined modality treatment strategies, especially chemo-radiation therapy, and also for the use of new radiation sensitizers.

CONCLUSION

We conclude that a more homogeneous approach to the pretreatment evaluation as well as treatment techniques is required in order to allow adequate quality control in any future trial of the RCG in the EORTC.

The benefit of Beam's eye view based 3D treatment planning for cervical cancer

PURPOSE

The aim of this study was to evaluate the possibility of Beam's eye view (BEV) based three dimensional (3D) treatment planning, to reduce portions of organs at risk included in the treated volume without increasing the risk of geographical miss in external beam therapy of cervical cancer.

MATERIALS AND METHODS

Three dimensional dose distribution of BEV based 3D treatment plans was compared to the 3D dose distribution derived from a four-field-box-technique using standard portals. A total of 20 patients with cervical cancer stage FIGO IIB and FIGO IIIB was included. Dose distribution in the target volumes and in the organs at risk of BEV based treatment planning, was compared to the dose distribution of the standard field technique using dose-volume-histograms.

RESULTS

In 4/20 patients (20%) a geographical miss at the cervix uteri was observed for the standard field technique. The BEV based treatment planning resulted in an adequate coverage of target volume and additionally in a reduction of portions of bladder and bowel volume included in the treated volume (-13.5, -10%). In contrast the BEV based technique resulted in an increase of portions of the rectum volume included in the treated volume compared to standard portals due to a shift of the rectum by the enlarged cervix uteri from its posterior to a lateral position. An overall 7% reduction of treated volume was observed, although the maximum width of lateral fields increased for the BEV technique. Moreover, we have found a remarkable impact of bladder fillings on the amount of bowel and bladder volume included in the treated volume.

CONCLUSION

BEV based 3D treatment planning for external beam therapy of cervical cancer offers a possibility to avoid geographical miss of part of the CTV with reduced portions of bladder and bowel volume included in the treated volume.

New techniques in the radiotherapeutic treatment of gynecological malignancies

The management of patients with gynecological malignancies serves as a prominent example of the importance of multi-modality oncologic therapy. Optimal treatment of these patients requires the skillful implementation of surgery, radiation therapy and chemotherapy. The decision to use simple versus combined modality therapy is crucial and best carried out in centers in which an experienced and coordinated multidisciplinary team is available. In this article, we have reviewed the most recent data regarding the role of radiation therapy in gynecological malignancies and have pointed out those areas where additional confirmatory studies are needed.

Magnetic resonance imaging in the treatment planning of radiation therapy in carcinoma of the cervix treated with the four-field pelvic technique

PURPOSE

To evaluate magnetic resonance imaging (MRI) in the planning of radiation therapy for patients with carcinoma of the cervix treated with a four-field technique.

METHODS AND MATERIALS

Between May 1994 and February 1995, 18 patients with carcinoma of the cervix were entered in the study (1 T1 N-; 2 T2a N-; 1 T2b NO; 10 T2b N-; 2 T2b N+; 2 T3b N+). Node status was assessed by a laparoscopic pelvic lymphadenectomy. During the first step, all the patients were simulated with an isocentric four-field pelvic technique. In one group (11 patients) simulation was done based on clinical examination, computed tomography (CT), and standard guidelines. In the second group (seven patients) simulation was based on clinical examination, CT, and with the help of diagnostic MRI, which was available at that time. During the second step, MRI in treatment position with skin markings of the isocenter of the radiation fields was then performed in every patient. During the third step, in each patient, the simulated radiation fields were correlated with the MRI defined target volume by superimposing them on midsagittal and midcoronal MR images. The adequacy of the margins was arbitrarly defined as 1 cm around the MRI defined target volume (tumor of the cervix and its extension, and uterus).

RESULTS

In the first group (11 patients), MRI in treatment position led to a change in 7 patients: six inadequate margins in the lateral fields and one in the anterior and lateral field. In almost all the cases, the adjustments were of an increase of 10 mm, equally matched between the anterior and posterior borders of the lateral fields. In the second group (seven patients), MRI in treatment position has led to a change in lateral fields in five patients. The mean adjustment was 10 mm: four increases (two anterior border, one posterior border, one anterior and posterior border), and one decrease of the posterior border. In the two groups, modifications of the anterior border of the lateral fields have allowed adequate margins around the uterine fundus and modifications of the posterior border have allowed adequate coverage of the cervical tumor.

CONCLUSION

When treating carcinoma of the cervix with a four-field radiation technique, standard portals do not exist. The design of lateral fields has to be based on individual morbid anatomy, which is given accurately by diagnostic MRI. Magnetic resonance imaging in treatment position assesses the design of simulated lateral fields.

Treatment planning for carcinoma of the cervix: a patterns of care study report

PURPOSE

The Patterns of Care Study (PCS) of patients treated in 1988-89 included "patterns of treatment planning" for radiotherapy of carcinoma of the uterine cervix. A Consensus Committee of radiation physicists and oncologists established current guidelines and developed questionnaires to assess the treatment planning process (i.e., the general structure, methodology, and tools) of institutions involved in the Patterns of Care Study. This paper reports the findings of the assessment.

METHODS AND MATERIALS

The PCS surveyed 73 radiotherapy facilities, of which 21 are academic institutions (AC), 26 hospital-based facilities (HB), and 26 free-standing centers (FS). In total, 242 cases were assessed with 39% from academic centers, 33% from hospital-based centers, and 28% from free-standing centers. The survey collected treatment planning information such as the use of computed tomography (CT), simulation procedure, contouring of patient outline, tumor or target delineation, identification of critical structures, method of dose prescription (point or isodose), etc. Data was also obtained concerning implant boosts, e.g., radioisotope used, use of midline block for external beam treatment, availability of remote afterloader, practice of interstitial implants, combination with hyperthermia, etc.

RESULTS

There is a high degree of compliance relative to the basic treatment planning standards. For example, 171 cases (out of 173) from AC and HB institutions included simulation and 169 used port film; for cases from FS centers, 61 out of 69 involved simulation and 66 out of 69 included port film. Most institutions used linacs (231 out of 242); in five cases, Co-60 units and in six cases betatron was used. In terms of treatment planning, 53% used skin contours, but only 14% had target volume delineation, with AC and HB being slightly more conscientious in these efforts. Critical organs did not appear to be explicitly considered in external beam treatment planning, with only 3% outlining the bladder, 5% the rectum, and less than 1% the small bowel. Only 11% of the centers used CT in treatment planning, and none reported the use of magnetic resonance imaging (MRI). For patients receiving implants, about 40% had midline blocking during external beam treatment, of which one out of three were shielded by standard blocks and two out of three with customized ones. About 11% of the patients receiving implants were treated with remote afterloading devices, 5% received interstitial implants, and none were treated in combination with hyperthermia.

CONCLUSION

The treatment planning aspects of radiotherapy of carcinoma of the cervix have been established by this Patterns of Care Study Survey. There is a high level of uniformity in the approach. Some variations exist among centers in the different strata.

Time course and incidence of late complications in patients treated with radiation therapy for FIGO stage IB carcinoma of the uterine cervix

PURPOSE

To determine the time course and incidence of late complications from radiation therapy in patients treated with radiation for FIGO Stage IB carcinoma of the uterine cervix, and to evaluate patient and tumor factors associated with an increased probability of treatment complications.

METHODS AND MATERIALS

The medical records of 1784 patients with FIGO Stage IB cervical carcinoma who were treated with initial radiation therapy between 1960 and 1989 were retrospectively reviewed. Follow-up was obtained from clinic visits and correspondence with patients and their physicians. Treatment complications were graded retrospectively. Complication rates were calculated actuarially; patients who died of disease or intercurrent illness without experiencing a major complication were censored at the time of death. There were 1241, 924, 548, and 274 patients followed for more than 5, 10, 15, and 20 years, respectively.

RESULTS

Of patients treated for Stage IB cervical carcinoma, 7.7% and 9.3% had experienced major (> or = Grade 3) complications at 3 and 5 years, respectively. After 5 years, there was a small but continuous risk of approximately 0.34% per year, resulting in an overall actuarial risk of having had major complications of 14.4% at 20 years. The risk of developing major urinary tract complications was approximately 0.7% per year for the first 3 years of follow-up, decreasing to about 0.25% per year for at least 25 years. In contrast, the risk of developing rectal complications was about 1% per year during the first 2 years, with a subsequent sharp decline to about 0.06% per year between Years 2 and 25. The risk of fistula formation was approximately doubled in the 234 patients who underwent adjuvant extrafascial hysterectomy (5.3 vs. 2.6% at 20 years; p = 0.04) and in the 111 patients who had pretreatment laparotomy (5.2 vs. 2.9%; p = 0.007). The risk of developing small bowel obstruction was increased in patients who underwent pretreatment laparotomy (14.5 vs. 3.7% at 10 years; p < 0.0001) and in patients who weighed < 120 pounds (8.2 vs. 3.6%; p = 0.004), but was not increased in patients who underwent adjuvant hysterectomy. A significantly greater risk of gastrointestinal complications was observed in black and non-Hispanic white patients than in Hispanic women (p = 0.01), even though there was no difference in the rate of developing urinary tract complications (p = 1.0). There was no correlation between the actuarial risk of developing major complications and the patients' age at the time of treatment, but the cumulative risk was greater for patients who were treated at a young age because these patients were more likely to survive to be exposed to a very long period of risk.

CONCLUSIONS

Using techniques described by Fletcher and Delclos, the risk of major complications from aggressive irradiation for Stage IB carcinoma of the cervix is low and does not warrant compromises in the intensity of treatment that might decrease the high cure rates achieved in such patients. The long time course of some late complications also suggests that continued surveillance of survivors, by physicians experienced in the diagnosis and management of the sequelae of the curative radiation treatment of cervical cancer, is important.

Conventional four-field pelvic radiotherapy technique without computed tomography-treatment planning in cancer of the cervix: potential geographic miss and its impact on pelvic control

PURPOSE

To evaluate the impact of inadequate margins on pelvic control using the conventional four-field pelvic portals without computed tomography (CT)-treatment planning.

METHODS AND MATERIALS

Between 1986 and 1991, 34 patients with invasive cancer of the cervix were eligible for outcome study of conventional four-field radiation therapy (10 Stage I, 16 Stage II, 8 Stage III). The eligibility for this study includes four-field pelvic technique, definitive radiation therapy, and diagnostic CT scan of the pelvis. For this study, an inadequate margin is arbitrarily defined as < or = 1.0 cm of normal tissue around the CT-defined tumor volume.

RESULTS

All 34 patients had adequate margins for anterio-posterior/posterio-anterior portals. However, 19 patients had an inadequate margin at the posterior border (S2-S3 interspace) and/or custom-shaped rectal block for lateral pelvic portals. Two patients had inadequate margins at the anterior border (level of symphysis pubis) due to an enlarged uterus. With a median follow-up of 36 months, pelvic control for adequate margins and inadequate margins was 100% and 71% for Stage IB disease and 88% and 50% for Stage IIB disease, respectively. However, pelvic control for Stage IIIB disease was 50% for both groups. There was no difference in total dose to point A or point B between the two groups.

CONCLUSION

Our preliminary data show higher local failure in patients with an inadequate margin. For four-field pelvic radiation therapy, we strongly recommend CT-treatment planning. Otherwise, anterio-posterior/posterio-anterior pelvic therapy is the most reliable treatment for cancer of the uterine cervix.