Hoon K. Lee

Postoperative pulmonary complications after preoperative chemoradiation for esophageal carcinoma: Correlation with pulmonary dose-volume histogram parameters

PURPOSE To clarify the relationship between the percentage of lung receiving low radiation doses with concurrent chemotherapy and the occurrence of postoperative pulmonary complications in the treatment of esophageal carcinoma. METHODS From 117 patients who underwent preoperative chemoradiation for esophageal cancer at our institution between 1998 and 2002, we selected 61 patients for whom complete pulmonary dose-volume histogram (DVH) data were available and analyzed the incidence of pneumonia and acute respiratory distress syndrome (ARDS) in this group. All patients received concurrent chemoradiation therapy, and 39 patients also received induction chemotherapy before concurrent chemoradiation. The median age was 62 years, and the median radiotherapy dose was 45 Gy. The percentage of lung volume receiving at least 10 Gy (V10), 15 Gy (V15), and 20 Gy (V20) were recorded from each pulmonary DVH. RESULTS Eleven (18%) of the 61 patients had pulmonary complications, 2 of whom died after progression of pneumonia. Pulmonary complications were noted more often (35% vs. 8%, p = 0.014) when the pulmonary V10 was > or =40% vs. <40% and when the V15 was > or /=30% vs. < 30% (33% vs. 10%, p = 0.036). An apparent increase in pulmonary complication rate when V20 was > or =20% vs. <20% (32% vs. 10%, p = 0.079) was not significant. None of the other factors analyzed (surgical procedure, tumor location, use of induction chemotherapy, use of concurrent taxane-based chemoradiation, or smoking history) was associated with the occurrence of pulmonary complications. The median hospital stay was 17 days for patients who had pulmonary complications vs. 12 days for patients who did not (p = 0.08). CONCLUSIONS The use of multimodality therapy may require minimization of lung volume irradiation to levels lower than previously expected. Radiotherapy techniques that decrease the volume of lung receiving low radiation doses may significantly reduce the risk of this potentially life-threatening complication.

Dosimetric consequences of using a surrogate urethra to estimate urethral dose after brachytherapy for prostate cancer.

PURPOSE To assess the accuracy and dosimetric consequences of defining a surrogate urethra at the geometric center of the prostate in postimplant CT scans. METHODS AND MATERIALS Eighty postimplant CT scans were obtained with a Foley catheter in place at Day 0 and at 1 month for 40 patients who had undergone (125)I prostate brachytherapy. The percentage of urethral volume receiving at least 275% of the prescribed dose (uV(275)), uV(250), uV(200), uV(150), maximal dose received by 90% of urethral volume (uD(90)), uD(70), uD(30), and uD(1) were measured for the Foley catheter and surrogate urethra. The distance between the Foley catheter and surrogate urethra was measured at the base, middle, and apex of the prostate. RESULTS A statistically significant difference was found in all the above-listed dosimetric parameters between the Foley catheter and surrogate urethra at Day 0 (p <or= 0.001). At 1 month, the uD(90), uD(70), and uD(1) remained significantly different between the Foley catheter and surrogate urethra (p <or= 0.05). The difference in the uV(275) (p = 0.055) and uV(150) (p = 0.059) between the Foley catheter and surrogate urethra showed a trend toward statistical significance at 1 month. The uV(250), uV(200), and uD(30) were greater for the surrogate urethra than for the Foley catheter at 1 month, but were not significantly different statistically. The mean distance between the Foley catheter and the surrogate urethra was greatest at the base (1.2 cm) in the vertical axis at Day 0 and decreased substantially to 0.87 cm at 1 month (p = 0.0004). CONCLUSION Using a surrogate urethra at the geometric center of the prostate may significantly overestimate the urethral dose at Day 0 and certain dosimetric parameters at 1 month. An alternative position for a surrogate urethra accounting for the difference in the location of the Foley catheter near the base of the prostate at Day 0 and 1 month could be considered in future studies.

The prognostic value of neurologic function in astrocytic spinal cord glioma

To assess the prognostic value of neurologic function (NF) in patients with astrocytic spinal cord glioma, we conducted a retrospective study of 25 patients who were treated at our institution between January 1970 and December 1999. The median age was 40 years, and the median follow-up was 54 months. Nineteen patients had a biopsy, 5 had a subtotal resection, and 1 had a gross total resection. Twenty-two patients received postoperative radiotherapy to a median dose of 45 Gy. NF ratings of 1 and 2 were considered favorable, and 3 and 4 were considered unfavorable, based on a scale of 1 to 4. Dual neuropathologic review confirmed the tumor to be low, intermediate, or high grade, based on the WHO grades I-II, III, or IV, respectively. Actuarial rates of local control (LC), progression-free survival (PFS), and overall survival (OS) were analyzed. Our study results revealed that an improved 5-year OS rate was associated with favorable NF at diagnosis (73% vs. 22% for patients with unfavorable NF; P = 0.04) and favorable NF before radiation therapy (89% vs. 28% for patients with unfavorable NF; P = 0.049). There was a significant difference in OS based on tumor grade ( P < 0.001) and age (risk ratio, 1.04; P = 0.027). PFS and LC were significantly better for young patients and those with lower tumor grade ( P < 0.05). A multivariate analysis of age, NF at diagnosis, and postoperative NF for all patients showed postoperative NF and age to be independent prognostic factors for OS. We conclude that favorable NF may be associated with improved outcome in patients with astrocytic spinal cord glioma.

IS INTRAOPERATIVE NOMOGRAM-BASED OVERPLANNING OF PROSTATE IMPLANTS NECESSARY?

PURPOSE Several investigators have described intraoperative planning of prostate implants based on a nomogram. The aim of this work was to investigate the adequacy of the nomogram in predicting the total activity necessary for optimal dosimetry. METHODS AND MATERIALS Eighty CT-based postimplant treatment plans were performed for patients who underwent ultrasound guided I-125 permanent implants alone between April 2000 and March 2001. The cohort of 40 patients had early stage (T1-T2) prostatic carcinoma and pre-treatment prostate volumes of 19-50 cc. I-125 seeds (0.391 mCi/seed) were implanted to achieve a distribution of 75% of the activity peripherally and 25% centrally. The CT studies were obtained on the day of (CT1) and at 1 month (CT2) after implant. All patients were catheterized at CT1, and 28 patients were catheterized at CT2 to visualize the urethra. For each patient, the percentage difference (dA) between the total implanted and nomogram predicted activity for a known prostate volume was calculated. The V200 (volume receiving 200% of the prescribed dose), V150, V100, V90, D100 (maximum dose received by 100% of the volume), D90, and D80 were measured for the prostate at CT1 and CT2. For the urethra, V275, V250, V200, and V150 were evaluated, and V100 and V70 were evaluated for the rectum. The Pearson test was used to correlate the dosimetric parameters with dA. Linear regression was used to fit the correlation of the volume and dose parameters with dA. RESULTS The median V100 at CT1 and CT2 was 91.8% and 94.2%, respectively. The Pearson test was significant for the prostate V100 and dA measured at CT1 (p = 0.005) but not at CT2 (p = 0.106). A similar correlation was found for the prostate D90 at CT1 (p = 0.002), but not at CT2 (p = 0.076). D100 (maximum dose received by 100% of volume) for prostate did not correlate with dA at CT1 (p = 0.094) and CT2 (p = 0.148). The volume of the prostate receiving higher doses (greater than 150% and 200% of the prescribed dose) correlated with dA. There were no significant correlations between V275, V250, V200, and V150 at CT1 and CT2 as a function of dA for the urethra. V100 and V70 for the rectum correlated significantly with dA; for V100, p = 0.041 at CT1 and p = 0.014 at CT2 and for V70, p = 0.041 at CT1 and p = 0.026 at CT2. A linear regression model fitted to the prostate data obtained from CT1 with the goal of achieving a V100 of 90% and D90 of 145 Gy suggests that no increase in the number of seeds may be warranted using intraoperative planning. The implants examined showed no concomitant increase of urethral doses with increase in activity relative to the nomogram, but showed an increase in the rectal doses for the same increase in activity. CONCLUSION The doses evaluated at CT1 represent an underestimate, whereas those obtained at CT2 represent an overestimate of the actual delivered protracted permanent implant dose. Based on these results and consideration of the dynamic nature of the dose distribution, target coverage obtained with intraoperative planning using the nomogram predicted activity is consistent with published guidelines for a quality implant and critical structure doses are within tolerance.

Outcomes using doxorubicin-based chemotherapy with or without radiotherapy for early-stage peripheral T-cell lymphomas

There is little information in the literature on outcomes using doxorubicin-based chemotherapy with or without radiotherapy for early-stage peripheral T-cell lymphomas. The purpose of this study was to analyze The University of Texas M.D. Anderson Cancer Center results in such patients. From 1985 to 1998, 39 patients with Stage I or II World Health Organization classification anaplastic large cell lymphoma (ALCL; n =20 ), peripheral T-cell lymphoma, unspecified (PTCLu; n =11 ), or nasal-type NK/T-cell lymphoma (NKTCL; n =8 ) were treated using doxorubicin-based chemotherapy (median, 6 cycles) with (n =24) or without (n =15) radiotherapy (median dose, 40 Gy). Median age was 41 years. Median follow-up of surviving patients was 85 months. Even though patients who presented with bulky disease or who achieved less than a complete response to chemotherapy were the ones typically treated with combined modality therapy rather than chemotherapy alone, there was no significant difference in local control (5-year rates: 60 vs. 70%, p =0.49 ), progression-free survival (5-year rates: 65 vs. 60%, p =0.62 ), or overall survival (5-year rates: 74 vs. 67%, p =0.47 ) between the groups treated with combined modality therapy and chemotherapy alone. Fifteen (38%) patients relapsed. Twelve relapses were limited to the initial site of disease; two involved the initial site and new sites, and one involved only new sites. Based on the significant risk of relapse at the initial site of disease, different approaches, including chemotherapy with concomitant radiotherapy to doses ≥ 45 Gy, warrant investigation.

ACR Appropriateness Criteria® Nonsurgical Treatment for Non-Small-Cell Lung Cancer: Good Performance Status/Definitive Intent

The optimal strategy for the non-surgical definitive treatment of patients with good performance status non-small cell lung cancer (mostly with locally advanced disease) has dramatically evolved over time. This article presents evidence-based data to review this literature. Several decades ago, the standard treatment for most stage III inoperable NSCLC was definitive radiation therapy alone. Randomized trials have since shown superior results with sequential chemotherapy and radiation, and more recently with concurrent chemoradiation, the current standard of care. Studies suggest a limited role for induction or adjuvant systemic therapy in addition to concurrent chemoradiation. The role of altered radiation fractionation techniques, such as hyperfractionation for locally advanced disease or hypofractionation for early stage disease is also discussed. More recently, the application of more advanced radiation techniques has been explored, including intensity modulated radiation therapy (IMRT) and proton beam radiation. Finally, various case variants are presented as examples of state-of-the-art treatment approaches.