Significance of computed tomography-measured volume in the prognosis of cervical carcinoma

Volumetric analysis at abdominal CT: oncologic and non-oncologic applications

Volumetric analysis is an objective three-dimensional assessment of a lesion or organ that may more accurately depict the burden of complex objects compared to traditional linear size measurement. Small changes in linear size are amplified by corresponding changes in volume, which could have significant clinical implications. Though early methods of calculating volumes were time-consuming and laborious, multiple software platforms are now available with varying degrees of user-software interaction ranging from manual to fully automated. For the assessment of primary malignancy and metastatic disease, volumetric measurements have shown utility in the evaluation of disease burden prior to and following therapy in a variety of cancers. Additionally, volume can be useful in treatment planning prior to resection or locoregional therapies, particularly for hepatic tumours. The utility of CT volumetry in a wide spectrum of non-oncologic pathology has also been described. While clear advantages exist in certain applications, some data have shown that volume is not always the superior method of size assessment and the associated labor intensity may not be worthwhile. Further, lack of uniformity among software platforms is a challenge to widespread implementation. This review will discuss CT volumetry and its potential oncologic and non-oncologic applications in abdominal imaging, as well as advantages and limitations to this quantitative technique.

Comparison of tumor volume, thickness, and T classification as predictors of outcomes in surgically treated squamous cell carcinoma of the oral tongue

BACKGROUND

As per TNM classification, superficial tumors with a favorable prognosis are fallaciously clubbed together with unfavorable, deeply infiltrating lesions in the same classification.

METHODS

This is a retrospective study of 588 patients with treatment-naive oral tongue cancers. Binary logistic regression was used to identify predictors of nodal metastasis and extracapsular spread (ECS) using tumor volume and thickness as separate models. The C-index was generated to quantify predictive accuracy of T classification, thickness, and tumor volume for survival.

RESULTS

Compared to T classification, tumor volume and thickness were better predictors of nodal metastasis and ECS. Predictive accuracy for disease-free survival (DFS) and overall survival (OS) given by C-index was equal and better for thickness (0.60 and 0.69) and tumor volume (0.61 and 0.69) as compared to T classification (0.59 and 0.64, respectively). For early-stage T1 to T2 oral tongue cancer, thickness is a better predictor of nodal metastasis as compared to tumor volume and T classification.

CONCLUSION

Concordance between the tumor thickness and volume proves that tumor thickness can be taken as a surrogate and reliable predictor of outcomes instead of calculating the tumor volume.

Volumetric Versus Unidimensional Measures of Metastatic Colorectal Cancer in Assessing Disease Response

INTRODUCTION

The purpose of this study was to compare unidimensional (1D/linear) and volumetric (3D) measures of metastatic colorectal cancer (mCRC) at computed tomography (CT) for predicting clinical outcome.

PATIENTS AND METHODS

Analysis of CT images in 105 patients (mean age, 59 years; range, 25-81 years; 45 women, 60 men) receiving treatment for mCRC was performed. Both unidimensional and volumetric measures were obtained on index lesions at 3 time points (baseline/midpoint/post-therapy; mean interval, 4.1 months; median, 3.7 months) by 3 readers using a semi-automated technique. Measurements were summed and compared using best overall response across the 3 time points. Patient response was categorized based on Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 thresholds for unidimensional and volume measures (CR, complete response; PR, partial response; SD, stable disease; PD, progressive disease). Survival data was correlated (mean follow-up, 19.9 ± 17.1 months; median, 14.7 months). Intra/interobserver variability and reproducibility of 1D and 3D measures was assessed. Cox survival and Kaplan-Meier models were constructed and compared.

RESULTS

Cox models and Kaplan-Meier curves for unidimensional versus volumetric assessment were very similar in appearance. Both 1D and 3D measurements effectively separated PD from the SD/PR groups, but neither separated SD from PR well. Volumetric measures showed comparable intra/interobserver variability on Bland-Altman analysis to unidimensional measures across readers using a semi-automated measurement technique. Metastatic site (lung, liver, node, other) did not seem to impact measurement reproducibility.

CONCLUSIONS

Although CT volumetric assessment of metastatic colorectal cancer is fairly reproducible by reader and site using a semi-automated technique, the ability to stratify progressive disease from other disease response categories in terms of survival was similar to unidimensional measurement.

Volumetric evaluation of hepatic tumors: multi-vendor, multi-reader liver phantom study

PURPOSE

To compare liver lesion volume measurement on multiple 3D software platforms using a liver phantom.

METHODS

An anthropomorphic phantom constructed with ten liver lesions of varying size, attenuation, and shape with known volume and long axis measurement was scanned (120 kVp, 80-440 smart mA, NI 12). DICOM data were uploaded to five commercially available 3D visualization systems and manual tumor volume was obtained by three-independent readers. Accuracy and reproducibility of linear and volume measurements were compared. The two most promising systems were then compared with an additional prototype system by two readers using both manual and semi-automated measurement with similar comparison between linear and volume measures. Measurements were performed on 5- and 1.25-mm data sets. Inter- and intra-observer variability was also assessed.

RESULTS

Overall mean % volume error on the five commercially available software systems (averaging all ten liver lesions among all three readers) was 8.0% ± 7.5%, 13.7% ± 11.2%, 14.2% ± 15.2%, 16.4% ± 14.8 %, and 16.9% ± 13.8%, varying almost twofold across vendor. Moderate inter-observer variability was present. Volume measurement was slightly more accurate than linear measurement, but linear measurement was more reproducible across readers and systems. On the two "best" systems, the manual measurement method was more accurate than the automated method (p = 0.001). The prototype system demonstrated superior semi-automated assessment, with a mean % volume error of 5.3% ± 4.1% (vs. 17.8% ± 11.1% and 31.5% ± 19.7%, p < 0.001), with improved inter- and intra-observer variability.

CONCLUSIONS

Accuracy and reproducibility of volume assessment of liver lesions varies significantly by vendor, which has important implications for clinical use.

CT volume measurement for prognostic evaluation of unresectable hepatocellular carcinoma after TACE

AIM: To analyze the value of computed tomography (CT) volume measurements for evaluation of the survival rate of unresectable hepatocellular carcinoma (HCC) patients after transcatheter arterial chemoembolization (TACE).

METHODS: One hundred and sixty-six unresectable HCC patients after TACE were involved in this retrospective study. Hepatic CT scan was performed for all patients before and 4 wk to 2 mo after TACE to define the morphologic features of HCC including its largest diameter, volume, product of the greatest axial dimension, tumor to liver volume ratio (TTLVR), and tumor shrinkage ratio. Clinical variables used in the study included gender, age, pattern of tumor growth, number of lesions, Child-Pugh classification of liver function, repeated TACE times, pre- or post-treatment α-fetoprotein (AFP) level, portal vein cancerous thrombus, tumor metastasis, degree of lipiodol retention within the tumor, and percutaneous ethanol injection. The correlation between survival time and clinical variables of patients or lesions was analyzed by combining morphologic features with the corresponding clinical and general data as input. A Cox proportional hazard model was used to analyze prognostic factors. The Kaplan-Meier method was used to calculate the cumulative survival time. Influence of the parameters on prognosis was analyzed by the log-rank test.

RESULTS: The overall 6, 12, 24, 36 and 60 mo cumulative survival rates were 78.92%, 49.85%, 23.82%, 15.60% and 8.92%, respectively. The median survival time was 12 mo. Univariate and multivariate analysis showed that only 4 parameters were the independent prognostic factors including TTLVR (χ² = 14.328, P < 0.001), portal vein cancerous thrombus (χ² = 5.643, P = 0.018), repeated TACE times (χ² = 8.746, P = 0.003), and post-treatment serum AFP level (χ² = 5.416, P = 0.020). When the TTLVR value was less than 70%, the survival time was inversely correlated with the TTLVR value.

CONCLUSION: CT volume measurement technique can predict the prognosis of unresectable HCC patients after TACE.

Value of pelvic examination and imaging modality for the evaluation of tumor size in cervical cancer

OBJECTIVE

The purpose of this study was to compare the accuracy of pelvic examination versus imaging modality such as computed tomography (CT) or magnetic resonance imaging (MRI) in the measurement of the tumor size of invasive cervical carcinoma based on pathologic findings.

METHODS

Patients with stage Ib-II cervical cancer who underwent primary surgical treatment between January 2003 and December 2005 were evaluated retrospectively. One hundred three consecutive patients aged 24 to 81 years (mean age, 50.6 years), who had not received any treatment previously were included in this study. Accuracy of preoperative CT or MRI versus pelvic examination in the measurement of tumor size was compared based on pathologic findings. All patients were examined and staged clinically by the gynecologic oncologist. Surgery was performed within 2 weeks after imaging studies. The data were analyzed using descriptive statistics.

RESULTS

The largest diameter of the tumor measured by pathologic findings was 2.76+/-1.76 cm. Based on pathologic findings, accuracy was estimated by the degree of agreement with a difference of <0.5 or 1.0 cm between the measurements of tumor size obtained by pelvic examination and imaging modality. Pelvic examination and imaging modality had an accuracy of 46.6% and 39.8%, respectively, with a difference of <0.5 cm, and an accuracy of 72.8% and 55.3%, respectively, with a difference of <1.0 cm. Correlation with pathologic findings was higher for pelvic examination (r(s)=0.680) than for imaging modality (r(s)=0.410). In determining the size of tumor mass differentiating >4.0 cm from </=4.0 cm, imaging modality showed higher accuracy than pelvic examination.

CONCLUSION

For the patients with stage Ib to II cervical cancer, pelvic examination is superior to imaging modality with regard to evaluation of the tumor size. However, imaging modality may be accurate for evaluating bulky tumors of cervical cancer.

Tumour volume estimated by computed tomography as a predictive factor in carcinoma of the tongue

This retrospective study evaluated tumour volume, estimated by computed tomography (CT), as a predictive factor in carcinoma of the tongue. Tumour volume was measured from pretreatment CT scans of 20 consecutive patients, followed up for at least 3 years, and this measurement was compared with tumour volume estimated from pathological specimens. T-stage and CT-derived tumour volume were compared with the clinical and pathological status of the nodes, and with the outcome of treatment. The measurement of tumour volume derived from CT correlated well with measurements derived from pathological examination, and tumour volume also predicted overall treatment failure. The disease-specific survival rate was 100% for patients with low-volume tumours (<13 cc) compared with 79% for those with stage T1 and T2 tumours.CT is a reliable way of measuring the volume of tumours in carcinoma of the tongue, and tumour volume is useful adjunct to the clinical tumour-node-metastases staging system.

[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.

Determination of tumour regression rates during radiotherapy for cervical carcinoma by serial MRI: comparison of two measurement techniques and examination of intraobserver and interobserver variability

Tumour regression rates of 11 patients with cervical carcinoma were estimated during external beam radiotherapy (EBRT) using serial MRI (average time interval 7 days; range 3-15 days). An average of five investigations (range 4-8) was performed per subject. Tumour volume was measured by two observers using the Cavalieri method of modern design stereology in combination with (a) planimetry and (b) point counting. The mean precision of all the volume estimates obtained by manually tracing the outline of the tumour was 6.6%. The mean precision obtained by counting an average of 176 points per investigation on the same transects was 6.7%. The intraobserver repeatability of planimetry, interobserver reproducibility of planimetry and point counting were excellent with no significant difference between the volume estimates obtained using either technique. Based on the planimetry measurements, initial tumour volumes ranged from 6.5 to 222 cm3 (mean 63 cm3, median 44 cm3). Based on the point counting measurements, initial tumour volumes ranged from 7.2 to 235 cm3 (mean 68 cm3, median 46 cm3). Tumour regression began within a few days of commencing EBRT and showed an exponential relationship with time (p < 0.01). There was good agreement between the regression rates obtained by planimetry and those obtained by point counting. No significant correlation was found between initial tumour volume and tumour regression rate for either planimetry or point counting. Planimetry measurements were, on average, obtained in about half the time taken for point counting (i.e. 30 min and 50 min, respectively). Although point counting is generally likely to be the more efficient approach, planimetry may be the preferred approach for estimating tumour volume when a purpose built track ball is available and the tumour morphology is relatively simple. Volume measurement should be obtained using the Cavalieri method to ensure that the estimates are unbiased and that their precision can be predicted. The measured tumour regression rates may have important implications for improving local tumour control, optimum timing of brachytherapy and minimizing the risk of radiation damage.

Computed tomography analysis of causes of local failure in radiotherapy for cervical carcinoma

BACKGROUND

The authors analyzed the radiation dose to the periphery of the cervix and area of the cervix in relation to local failure of radiotherapy for carcinoma of the cervix using computed tomography (CT) images.

METHODS

Between 1981-1990, 127 consecutive patients were treated with definitive radiotherapy. Ninety-nine of these patients had CT images taken at the time of intracavitary therapy. Of these 99 patients, 80 were eligible for this analysis. After CT scanning, isodose curves relative to the point A dose were superimposed on the CT images. The minimum percent dose and minimum dose at the periphery of the cervix were estimated. The area of the cervix also was measured. These factors were examined in relation to the local tumor control rate.

RESULTS

Histograms of both the minimum percent dose and the cervical area showed significant differences between the local control and local failure groups (P <0.001). The local control rates were related to both the minimum percent dose and the cervical area, and differed significantly over and below the values of 60% and 18 cm2 (P <0.001 each), respectively. The local control patients, over and below the line: Y = -0.220X + 21.2, in which X (gray [Gy]) and Y (Gy) are the whole pelvis dose and the minimum dose, respectively, could be well differentiated with significance (91.7% vs. 25.0%; P <0.001).

CONCLUSIONS

Computed tomography analysis indicated that the local tumor control rate was related strongly to the minimum percent dose, the cervical area, and the pair of whole pelvis and minimum dose values. These factors were found to be more useful than the point A dose in predicting local tumor control.

High-dose-rate intracavitary irradiation using linear source arrangement for stage II and III squamous cell carcinoma of the uterine cervix

PURPOSE

The purpose of this article is to evaluate fractionated high-dose-rate (HDR) intracavitary irradiation using linear source arrangement (LSA) for patients with squamous cell carcinoma of the uterine cervix.

MATERIALS AND METHODS

The subjects consisted of 217 patients (71 patients with stage II and 146 with stage III disease) who received external beam therapy (EBT) followed by fractionated HDR intracavitary irradiation using LSA between January 1980 and June 1990. In EBT, 40 Gy in 20 fractions (40 Gy/20 Fr) or 39.6 Gy/22 Fr was delivered to the whole pelvis and an additional 10 Gy/5 Fr or 10.8 Gy/6 Fr was delivered to the parametrium. The intracavitary irradiation dose was 30 Gy/6 Fr or 35 Gy/7 Fr with a daily fraction size of 5 Gy and two fractions per week. During the intracavitary treatment, most patients were treated on an out-patient basis.

RESULTS

Cause-specific 5-year survival rates were 77% for stage II and 50% for stage III. Pelvic failure rates were 13% for stage II and 36% for stage III. In multivariate analyses, improved cause-specific survival was significantly associated with stage II (P = 0.0003), higher pretreatment serum hemoglobin level (P = 0.0015), higher pretreatment serum total protein level (P = 0.0029), and shorter total treatment time (P = 0.0024). The rate of severe (grade 3 or 4) late complication was 2% for the rectum, 1% for the small intestine or sigmoid colon and 1% for the bladder.

CONCLUSIONS

Fractionated HDR intracavitary irradiation using LSA is an effective treatment for patients with uterine cervical cancer without need for hospitalization.

Impact of the extent of parametrial involvement in patients with carcinoma of the uterine cervix

PURPOSE

A scoring system is proposed to measure the extent of parametrial involvement and predict treatment outcome in patients with carcinoma of the uterine cervix.

METHODS AND MATERIALS

244 patients with FIGO Stage IIB (n = 146) or IIIB (n = 98) carcinoma of the uterine cervix were treated by radical radiotherapy from October 1987 to June 1992. Impact of the extent of parametrial involvement on outcome was studied. All patients were scored by the newly introduced scoring system described as follows: score 1, tumor extending <1/2 the distance to the pelvic side wall; score 2, tumor extending >1/2 the distance to the pelvic side wall but not to pelvic side wall; score 3, tumor extending to the pelvic side wall. The score in each patient was defined as the sum of the scores of both the left and right parametrial tumor extent.

RESULTS

There were 53, 47, 61, 34, 25, and 24 patients in score 1, 2, 3, 4, 5, and 6, respectively. All 244 patients were subdivided into three groups described as follows: score 1 and 2, group I; score 3 and 4, group II; score 5 and 6, group III. In univariate analysis, lower score groups had better overall survival rate (OS), disease-free survival rate (DFS), local control rate (LC), and distant metastasis-free rate (DMF) than higher score groups including groups I vs. II, II vs. III, or I vs. III. The differences were all statistically significant except for the difference of the DMF in group I vs. II. In multivariate analysis, score (range 1-6) was also statistically significant in OS (p < 0.0001), DFS (p = 0.0015), LC (p = 0.0032), and DMF (p = 0.0141).

CONCLUSIONS

The data suggested that the new scoring system defined by pelvic examination is a convenient, simple, and reliable method of measuring the degree of parametrial extension and predicting the outcome of patients with parametrial disease.

Analysis of prognostic factors in stage IIB-IVA cervical carcinoma treated with radiation therapy: value of computed tomography

PURPOSE

To define the influence of the tumor size measured by computed tomography (CT) and lymph node involvement detected by CT in patients treated with radiation therapy for Stage IIB-IVA carcinoma of intact uterine cervix.

METHODS AND MATERIALS

This was a retrospective analysis of 233 patients with uterine cervical cancer managed with both external irradiation and high-dose-rate intracavitary brachytherapy (HDR-ICR) at Kanagawa Cancer Center. The results were analyzed for the end points of absolute survival (AS), disease-free survival (DFS), pelvic control (PC), and central control (CC). The parameters of stage, CT-measured anterior-posterior (AP) cervix size, and CT-detected lymph node metastases were evaluated using univariate and multivariate analysis.

RESULTS

The stage, AP cervix size, and lymph node involvement were significant pretreatment factors in univariate analysis with respect to AS, DFS, PC, and CC. Multivariate analysis confirmed that significant risk was associated with certain prognostic parameters. Those in terms of AS, in order of decreasing significance, were lymph node involvement, AP cervix size, age, and total HDR-ICR dose. When DFS was studied, lymph node involvement and AP cervix size were demonstrated to have a significant effect. Stage and lymph node involvement significantly affected PC.

CONCLUSION

Because the International Federation of Gynecological Obstetrics staging system fails to incorporate important prognostic information about tumor volume and lymph node involvement, CT-detected lymph node metastases as well as CT-measured cervix size should be determined as complementary additional prognostic measures.

Factors influencing the accuracy of volume measurements in spiral CT: a phantom study

PURPOSE

The purpose of this study was to investigate the influence of different parameters (object size, shape, orientation, contrast, observer, and window setting) on the accuracy of volume measurements in spiral CT.

METHOD

The phantom study consisted of two parts. First, well-circumscribed ellipsoid objects were scanned with conventional and spiral CT. Volumes were determined by two observers using manual contour delineation and summation-of-areas. The influence of object size, CT technique, and observer was assessed. Second, irregularly shaped gingerroots were scanned and the effect of observer, contrast, and orientation was investigated. Also assessed in both parts of the study was the effect of window setting.

RESULTS

Spiral CT offered higher accuracy and reproducibility than conventional CT did. The accuracy of volume measurements was mainly determined by the window setting used for image display. Using an "optimized" window center value halfway between object density and background density resulted in overestimation of true object volumes if the number of slices through the object (number of samples) was low. Other factors (contrast, observer-related errors in contour delineation) were less important.

CONCLUSIONS

Volume measurements of small objects, obtained with spiral CT and using manual contour delineation, may be grossly erroneous. Major causes of inaccuracy are an inappropriate window center selection and undersampling.

Usefulness of tumor volumetry by magnetic resonance imaging in assessing response to radiation therapy in carcinoma of the uterine cervix

PURPOSE

Clinical evaluation of tumor size in cervical cancer is often difficult, and clinical signs of radiation therapy failure may not be present until well after completion of treatment. The purpose of this study is to investigate early indicators of treatment response using magnetic resonance (MR) imaging for quantitative assessment of tumor volume and tumor regression rate before, during, and after radiation therapy.

METHODS AND MATERIALS

Thirty-four patients with cervical cancer Stages IB [5], IIB [8], IIIA [1], IIIB [14], IVA [3], IVB [1], and recurrent [2] were studied prospectively with four serial MR examinations obtained at the start of radiation therapy, at 2-2.5 weeks (20-24 Gy), at 4-5 weeks (40-50 Gy), and 1-2 months after treatment completion. Tumor volume was assessed by three-dimensional volumetric measurements using T2-weighted images of each MR examination. The volume regression rate was generated based on the four sequential MR studies. These findings were correlated with local control, metastasis rate, and disease-free survival. Median follow-up was 18 months (range: 9-43 months).

RESULTS

The tumor regression rate after a dose of 40-50 Gy correlated significantly with treatment outcome. The actuarial 2-year disease-free survival was 88.4% in patients with tumors regressing to < 20% of the initial volume compared with 45.4% in those with > or = 20% residual (p = 0.007). The incidence of local recurrence was 9.5% (2 out of 21) and 76.9% (10 out of 13), respectively (p < 0.001). Analysis by initial tumor volume showed that this observation was valid in patients with initial volumes between 40 and 100 cm3. Analysis by FIGO stage confirmed this observation in all patients except those with Stage IB.

CONCLUSION

Sequential tumor volumetry using MR imaging appears to be a sensitive measure of the responsiveness of cervical cancer to irradiation. Treatment response can be assessed as early as during the course of radiation therapy by measurement of initial tumor volume and regression rate at 40-50 Gy. In patients with large (> 40 cm3) and advanced (Stage > or = IIIA) tumors, this technique may be helpful in supplementing the clinical examination for response assessment. The identification of patients at high risk for treatment failure may ultimately lead to improved clinical outcome.

Dose-volume histogram analysis of high dose rate intracavitary brachytherapy for uterine cervix cancer

PURPOSE

We retrospectively analyzed the relationship between dose distribution and local control using a dose-volume histogram (DVH) in patients with cancer of the uterine cervix treated by definitive radiotherapy including intracavitary brachytherapy.

METHODS AND MATERIALS

Twenty-five patients with squamous cell carcinoma of the uterine cervix who underwent definitive radiotherapy between August 1987 and April 1994 were selected for the present study. They included 15 patients with local control and 10 patients with local recurrence. In principle, these patients were treated with 50 Gy of external beam pelvic radiotherapy and a point A dose of 24 Gy, in four fractions, of intracavitary brachytherapy. The DVHs of tumor volumes were calculated by superimposing three-dimensional (3D) dose distributions on computed tomography (CT) images taken before brachytherapy.

RESULTS

Differential DVHs revealed a tendency for the portion of the total tumor volume to which the delivered dose was low to be larger in patients with local recurrence. The tumor volumes and the absolute dose volumes of which the absorbed dose was less than 24 Gy [DV (< 24 Gy)] were significantly larger in patients with local recurrence than those in local control patients (p = 0.02 and 0.03, respectively). The percent DV (<24 Gy) was not significantly different in the two groups. In patients with larger tumor volume, the absolute DV (<24 Gy) was also larger and a strong linear correlation was noted between them.

CONCLUSIONS

The analysis of dose distribution of brachytherapy using DVH was useful to evaluate the quality of dose distribution quantitatively. The absolute dose volume was considered more important than the percent dose volume for evaluation of the clinical outcome. Our study suggested that unfavorable dose distribution for the tumor volume in brachytherapy was one of the reasons of poor local control in patients with large tumor volume.

Prognostic value of cervical size and pelvic lymph node status assessed by computed tomography for patients with uterine cervical cancer treated by radical radiation therapy

PURPOSE

To determine the prognostic impact of cervical size and pelvic lymph node status assessed by computed tomography (CT) in uterine cervical carcinoma treated with irradiation alone.

METHODS AND MATERIALS

Seventy patients with International Federation of Gynecology and Obstetrics (FIGO) Stage IIB and IIIB uterine cervical squamous cell carcinoma treated with a combination of external and high dose-rate intracavitary irradiation were entered into analyses. Univariate and multivariate analyses using the Cox regression model were performed to determine statistical significance of some tumor-related factors.

RESULTS

There were no significant differences in pelvic control rate (PC), distant metastases-free rate (DMF), cause-specific disease-free survival rate (CSDFS) among subgroups with cervix < 60 mm in diameter. However, PC (p = 0.023), DMF (p = 0.000025), and CSDFS (p = 0.0023) were significantly lower for patients with cervix > or = 60 mm than < 60 mm. The 5-year CSDFS was 77.5% for < 60 mm, and 28.6% for > or = 60 mm. Pelvic node status assessed by CT scans had significant prognostic impact on outcome. the 5-year CSDFS rate was 84.9% for patients with no enlarged nodes, and 58.9% for those with enlarged nodes greater than 1 cm in minimum diameter (p = 0.023). Whereas PC was not significantly affected, the DMF was strongly correlated with nodal status (p = 0.00027). Pelvic node status was taken as an independent predictor for DMF (p = 0.019) on multivariate analysis.

CONCLUSION

Although cervical size assessed by CT had limited prognostic value, pelvic node status assessed by CT is the significant prognostic factor for patients with uterine cervical carcinoma treated with radical irradiation.

Heuristically derived tumor burden score as a prognostic factor for stage IIIB carcinoma of the cervix

PURPOSE

A retrospective analysis of radiotherapeutic management of locally advanced carcinoma of the uterine cervix was performed to evaluate the effect of various treatment parameters and disease extent upon treat outcome.

METHODS AND MATERIALS

Between 1976 and 1989, 89 patients with Stage IIIB disease were treated with external beam radiotherapy and brachytherapy. Treatment outcomes were evaluated by dose to Point A, the proportion of Point A dose delivered by brachytherapy, clinical response at 3 months, and a newly developed tumor burden scoring system that quantifies the anatomical extent of disease. Kaplan-Meier estimates of tumor control and survival parameters were determined.

RESULTS

Loco-regional control (LRC), disease-free survival (DFS), and overall survival (OVS) at 5 years were 52.9%, 45.5%, and 50.3%, respectively. Clinical response at 3 months was highly predictive of local and distant tumor control. There was no correlation between proportion of brachytherapy dose and treatment outcome. The tumor burden scoring system demonstrates that FIGO Stage IIIB disease can be clinically divided into two prognostic groups of low and high tumor burden. Five year LRC was 62.9% and 40.2% for the low and high tumor burden groups, respectively (p = 0.024). Within the high tumor burden group the LRC was 53.0% and 22.5% when the point A dose given was > 78 Gy and < or = 78 Gy, respectively (p = 0.047). This correlated with improved DFS and OVS.

CONCLUSION

The tumor burden scoring system subdivides FIGO Stage IIIB cervical carcinoma into two prognostic groups, predicting for overall survival and demonstrating a dose response in the high tumor burden group. This system may serve to improve future comparison of treatment outcome and to guide selection of patients who may benefit from a more aggressive treatment approach.