Who would be the winner? A prognostic nomogram for predicting the benefit of postoperative radiotherapy ± chemotherapy in patients with locally advanced gastric cancer: TROD-02-01 study

OBJECTIVES

We aimed to develop a basic, easily applicable nomogram to improve the survival prediction of the patients with stage II/III gastric cancer (GC) and to select the best candidate for postoperative radiotherapy (RT).

METHODS

In this multicentric trial, we retrospectively evaluated the data of 1597 patients with stage II/III GC after curative gastrectomy followed by postoperative RT ± chemotherapy (CT). Patients were divided into a training set (n = 1307) and an external validation set (n = 290). Nomograms were created based on independent predictors identified by Cox regression analysis in the training set. The consistency index (C-index) and the calibration curve were used to evaluate the discriminative ability and accuracy of the nomogram. A nomogram was created based on the predictive model and the identified prognostic factors to predict 5-year cancer-specific survival (CSS) and progression-free survival (PFS).

RESULTS

The multivariate Cox model recognized lymph node (LN) involvement status, lymphatic dissection (LD) width, and metastatic LN ratio as covariates associated with CSS. Depth of invasion, LN involvement status, LD width, metastatic LN ratio, and lymphovascular invasion were the factors associated with PFS. Calibration of the nomogram predicted both CSS and PFS corresponding closely with the actual results. In our validation set, discrimination was good (C-index, 0.76), and the predicted survival was within a 10% margin of ideal nomogram.

CONCLUSIONS

In our relatively large cohort, we created and validated both CSS and PFS nomograms that could be useful for underdeveloped or developing countries rather than Korea and Japan, where the D2 gastrectomy is routinely performed. This could serve as a true map for oncologists who must make decisions without an experienced surgeon and a multidisciplinary tumor board.

The Effect of Clinical (Anatomical) and Prognostic Stage Groups on Survival in Patients Diagnosed with Breast Cancer: MULTI-Center Study Results, TROD Breast Cancer Study Group

PURPOSE/OBJECTIVE(S)

The American Joint Committee on Cancer (AJCC) anatomic stage groups have arguably been the most powerful method in predicting breast cancer outcomes. In the present study, we aimed to determine the differences between anatomical stage and clinical prognostic stage groups, which were obtained by adding biological markers such as histologic tumor grade, estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 status to patients diagnosed with breast cancer, the rate of change in stage, and the effect of stage change on survival.

MATERIALS/METHODS

The study protocol was sent to all radiation oncology centers in Türkiye. Four centers enrolled their patients to the study. A total of 1470 stage I-III breast cancer patients with complete information on biological markers (histologic tumor grade, hormone receptor, and c-erb B2 receptor status), haven't been treated with neoadjuvant therapy were included to the study and evaluated retrospectively. The 8th edition of AJCC consolidated biological markers in to clinical prognostic stage groups. Kaplan-Meier curves were used to estimate survival. The log-rank test was used to compare the difference between groups. The Cox proportional-hazards regression model was used to determine the association between anatomic-prognostic stage, disease-free survival (DFS), and overall survival (OS).

RESULTS

The median follow-up time was 82 (6-237) months. Median age of the patients was 52 years (20-88) and 865 cases (58.8%) were in the postmenopausal period. The axillary lymph node status was negative (N0) in 765 patients (52.1%). Tumor grade was grade I in 200 patients (13.6%), grade II in 812 patients (55.2%) and grade III in 452 patients (30.7%). Estrogen receptor status was positive in 1247 patients (84.8%), PR status was positive in 1178 patients and Her2-neu status was positive in 207 patients (14.1%). A stage change has been identified in a total of 777 patients (52.9%). Compared with the anatomic stage groups, application of the clinical prognostic stage groups assigned 46.4% cases lower and 6.5% cases higher stage. Five- and ten-year OS and DFS rates of the patients are 73.7%, 44.3% and 91.9%, 86.3% respectively. Age (p<0.001), tumor grade (p<0.001), ER status (p<0.001), PR status (p<0.001), cerbB2 receptor status (p = 0.025) were found to be statistically significant variables in multivariable analysis for OS. For DFS, multivariable analysis showed that age (p = 0.027), tumor grade (p = 0.005), anatomical stage (p<0.001) and assigned to higher stage (p = .001) were statistically significant variables.

CONCLUSION

Hormone receptors and c-erb B2 receptor status are independent variables which impact OS and DFS in our patient group which is mostly consisted of early-stage cases according to anatomical stage. In prognostic staging, upstaging stands out as an independent prognostic factor for DFS. The 8th edition of AJCC prognostic stage groups determines the prognosis much better in our patient cohort.

The Effect of Deep Inspiration Breath-Hold Technique on Right Coronary Artery, Heart, and Liver Doses in Right Breast Cancer Radiotherapy

PURPOSE/OBJECTIVE(S)

The deep inspiration breath-hold (DIBH) approach has been thoroughly researched with the aim of reducing radiation exposures to normal tissues in breast cancer patients. Although heart and lung toxicity are widely addressed in many literature, radiation-associated liver toxicity and dose constraints for the right coronary artery (RCA) are not well studied in relation to breast radiotherapy. Additionally, very few studies have investigated the relationship between doses to cardiac substructures. This study aimed to determine the effect of the DIBH technique on the right coronary artery (RCA) region, cardiac substructures, and liver dose in right breast cancer irradiation.

MATERIALS/METHODS

Between January 2022 and December 2022, thirty-five right breast cancer patients who previously received breast-surgery underwent computed tomography (CT) simulation with both free-breathing (FB) and DIBH techniques. Patients were contoured by a radiation oncologist on the scans using the Treatment Planning System. For cardiac substructures, reference atlas contours were used for accurate delineation and to reduce inter-observer variation. Each patient underwent two treatment plans for both the DIBH and FB datasets. The plan comprised the FB and DIBH techniques, and the doses to the cardiac substructures, ipsilateral lung, RCA region, and liver were compared using a two-tailed paired t-test. Radiotherapy was delivered with a Linac with the prescription dose of 50 Gy in 25 fractions.

RESULTS

For both FB and DIBH irradiation groups, the mean radiation doses to the ipsilateral lung, heart, and RCA region in patients with FB and DIBH techniques were; 14.67 Gy, 2.33 Gy, 4.88 Gy and 12.05 Gy, 1.34 Gy and 3.29 Gy respectively. The mean radiation doses to the cardiac substructures; for the left ventricle, right ventricle, left atrium, and right atrium for the FB were 1.08 Gy, 1.79 Gy, 4.11 Gy, and for DIBH, 0.49 Gy, 1.49 Gy, 0.95 Gy, and 2.61 Gy, respectively. For the DIBH group, the liver maximum dose (p<0.01), right lung mean dose (p = 0.001), heart maximum dose (p = 0.009), RCA mean dose (p = 0.020), RCA maximum dose (p = 0.008), RCA V5 dose (p = 0.035), right atrium maximum dose (p = 0.009) and right ventricle mean dose (p = 0.040) were significantly lower than in patients treated in the non-gated group.

CONCLUSION

DIBH resulted in considerable displacement of the liver away from the high-dose target region, such that the volume of liver in the high-dose region was reduced. Additionally, the use of the DIBH technique in right breast cancer irradiation effectively reduces the radiation doses to the cardiac substructures, such as the left ventricle, right ventricle, left atrium, right atrium, RCA region, and lungs. DIBH could lead to substantial sparing of these structures with the right breast cancer radiotherapy. Future prospective studies are required to determine whether improvements to dose-distribution will translate into improved toxicity outcomes.

Revisiting the Radical Radiotherapy-Radiochemotherapy Results in Anal Canal Cancers: (TROD Gastrointestinal Group Study 02-005)

BACKGROUND AND AIM

This study aimed to determine treatment outcomes and factors affecting prognosis in patients diagnosed with anal canal cancer who received radical radiotherapy (RT) or radiotherapy combined with chemotherapy (CT-RT) in radiation oncology centers in Turkey and compare the results with literature.

MATERIAL AND METHOD

The study included 193 patients with anal canal cancer reported between 1995 and 2019, of which 162 had complete data. The study was conducted in 11 radiation oncology centers, and a joint database was shared among them. Patients received radiotherapy doses of 45 Gy to 60 Gy. Data analysis was done using SPSS for Windows version 20.

RESULTS

Median follow-up was 48.51 months (2-214). All patients received radiotherapy, and 140 (86.4%) received concurrent chemotherapy. Radiotherapy doses of 50.4 Gy to 60 Gy were administered to 74 patients (45.7%) using 2-dimensional-3-dimensional (2D-3D) conformal therapy and 70 patients (43.2%) using intensity modulated radiotherapy technique (IMRT). Acute phase hematologic toxicity was observed in 62 patients (38.3%), and nonhematologic toxicity in 123 patients (75.9%). The 5-year overall survival (OS) rate was 75.1% and disease-specific survival (DSS) rate was 76.4%. OS without colostomy was achieved in 79,8 % at 5 years, and complete response in 112 patients (69.1%). OS rate was significantly higher in 142 patients with positive response (P < .000) and 112 with complete response (P < .000). Anemia (P < .002), local progression, and systemic progression (P < .000) resulted in lower OS (P < .002). In univariate analysis, factors affecting OS rate were: gender, age, stage, lymph node status, T stage, RT treatment duration, and treatment planning with PET fusion, which were found to be statistically significant. Completing radiotherapy in less than 45 days, concurrent chemotherapy, and continued administration of mitomycin and 5 FU as chemotherapy had a significant positive effect on overall survival. OS rate was higher in patients receiving RT dose of 58 Gy or less and undergoing IMRT planning in radiotherapy. IMRT was associated with lower acute and late side effects.

CONCLUSION

Radiochemotherapy is the primary treatment for anal canal cancer and advanced radiotherapy techniques may increase survival by reducing side effects and improving treatment continuation. Higher treatment doses require further investigation. The efficacy of treatment can be improved by including patients treated with modern radiotherapy techniques in multicenter prospective studies using new and more effective chemotherapy and immunotherapy agents.

The importance of mesorectum motion in determining PTV margins in rectal cancer patients treated with neoadjuvant radiotherapy

New precision radiotherapy (RT) techniques reduce the uncertainties in localizing soft and moving tumors. However, there are still many uncontrollable internal organ movements. In our study, patients who underwent neoadjuvant chemoradiotherapy (NA-CRT) for rectal cancer were evaluated to determine inter-fraction mesorectum motion and dosimetric changes. Fourteen patients treated with NA-CRT for rectal cancer between 2014 and 2016 were included in the analysis. The mesorectum and clinical target volume (CTV) were delineated on planning computed tomography (CT) and cone-beam CT (CB-CT) scans. After planning with a volumetric modulated arc therapy (VMAT) plan, re-planning was performed on all CB-CTs. Finally, the volumetric and dosimetric changes of PTV and mesorectum were evaluated in all CB-CTs compared with the initial CT and VMAT plans. The geometrical center of mesorectum volume in CB-CTs had moved 1 (0.2-6.6), 1.6 (0.2-3.8) and 1.6 (0-4.9) mm in the x, y and z-axis respectively compared with the initial CT. The dosimetric parameters of PTV including D2, D95 and D98 on CB-CT showed a median 47.19 (46.70-47.80), 45.05 (44.18-45.68) and 44.69 (43.83-45.48) Gy and median 1% (1-2), 0% (0-2) and 1% (0-2) dosimetric change compared with the initial VMAT plan. In our study, we have shown that the mesorectum has moved up to 20 mm in the lateral and anterior-posterior direction and almost 10 mm in the superior/inferior direction during RT, causing a median of ~2% change in dosimetric parameters. Therefore, these movements must be considered in determining PTV margins to avoid dosimetric changes.

Paclitaxel-Carboplatin Induced Radiation Recall Colitis

Some chemotherapeutic agents can “recall” the irradiated volumes by skin or pulmonary reactions in cancer patients who previously received radiation therapy. We report a recall colitis following the administration of paclitaxel-containing regimen in a patient who had been irradiated for a carcinoma of the uterine cervix. A 63-year-old woman underwent a Wertheim operation because of uterine cervix carcinoma. After 8 years of follow-up, a local recurrence was observed and she received curative external radiotherapy (45 Gy) to the pelvis. No significant adverse events were observed during the radiotherapy. Approximately one year later, she was hospitalized because of metastatic disease with multiple pulmonary nodules, and a chemotherapy regimen consisting of paclitaxel and carboplatin was administered. The day after the administration of chemotherapy the patient had diarrhea and rectal bleeding. Histological examination of the biopsy taken from rectal hyperemic lesions showed a radiation colitis. The symptoms reappeared after the administration of each course of chemotherapy and continued until the death of the patient despite the interruption of the chemotherapy. In conclusion, the probability of recall phenomena should be kept in mind in patients who received previously with pelvic radiotherapy and treated later with cytotoxic chemotherapy.

Psychosexual and Body Image Aspects of Quality of Life in Turkish Breast Cancer Patients: A Comparison of Breast Conserving Treatment and Mastectomy

Aims and background

Assessing psychosexual and body image aspects of quality of life in Turkish breast cancer patients treated by either mastectomy or breast conserving treatment (BCT).

Methods

The study group consisted of 112 patients who had undergone all treatment at a single institution under the care of a multidisciplinary breast team. Following surgery all patients underwent adjuvant radiotherapy with or without chemotherapy and hormone therapy. At the time of this study all patients were disease free with at least 2 years' follow-up. Twenty percent of the patients were premenopausal and 80% postmenopausal. The patients completed a questionnaire consisting of 42 questions related to their sexual relations and body image.

Results

Forty-one percent of sexually active patients had experienced a deterioration of sexual functioning after treatment. This was mainly due to loss of libido (80%), loss of interest in partner (54%), and sexual dissatisfaction (59%). Problems tended to develop early in the course of treatment. Decreased sexual desire was significantly more frequent in patients undergoing mastectomy versus BCT (80% vs 61%; P = 0.043) and in premenopausal versus postmenopausal patients (P= 0.024). Although 80% of patients were satisfied with their apperance as a whole, only 54% liked their naked bodies. There was no significant difference in body image scores between patients undergoing mastectomy or BCT apart from a general feeling of physical unattractive-ness in mastectomy patients (3.4 vs 2.8; P = 0.03).

Conclusions

Significant, similar psychosexual and body image problems occur in patients treated for breast cancer with either mastectomy or BCT. Problems arise early in the course of the disease and therefore detection and treatment of these problems should be addressed during the patients' initial assessment and at the start of treatment. These findings are similar to those reported on similar groups of treated women in American and European populations.

Abstract 1602: Effects of Letrozole and radiotherapy on cell cycle and death in a breast cancer cell line

Preclinical and clinical studies have shown that hormone receptor-positive tumors have molecular, biological and clinical differences. Tamoxifen is the standard endocrine therapy in premenopausal women, whereas in ER (+), postmenopausal patients the optimal adjuvant hormonal therapy is aromatase inhibitors either as initial therapy or after tamoxifen treatment. Studies have shown that concurrent use of tamoxifen sensitizes cells to radiotherapy (RT) and increases RT induced pulmonary fibrosis. We aimed to investigate biological effects of the concurrent use of letrozole with radiotherapy on the breast cancer cells; using cell lines MCF7, which does not express the aromatase enzyme; and MCF7aro which is a aromatase expressing subclone. Cells were exposed to letrozole at varying doses of 100, 500, 1000 nM; for 24, 72 and 144 hours. Irradiations were performed using a cobalt-60 source with doses 2 and 4 Gy. Cell death was evaluated by measuring caspase 3 activation and by cell surface annexin V / PI staining. Beclin expression levels were determined by western blot. Cell cycle analyses were performed by DNA content staining/flow cytometry. All experiments were done in triplicates. Caspase-3 and annexin-V / PI results showed no significant difference for early apoptosis, late apoptosis and necrosis between the letrozole treated and untreated aromatase non-expressing MCF7 cells. In the aromatase expressing MCF7aro cells, we observed that there was a general reduction in cell death in cells treated with letrozole; with a trend towards apoptosis as a cell death modality rather than necrosis. We also observed increased beclin protein levels -which may imply an increase in autophagy- in MCF7 cells which have received 4 Gy irradiation, independent of the presence of letrozole indicating an acute stress response when expose to high doses of radiation. On the other hand beclin levels were increased in all experimental groups of MCF-7aro cells independent of the presence letrozole and/or radiation dose which supports the notion of an autophagic response under stress. The presence of the aromatase gene itself may be a positive factor for cell survival under stress conditions. Cell cycle analyses revealed 5% more cells accumulated at G1 in letrozole treated MCF7aro cells. Our preliminary findings suggest a reduction of cell death in hormone-sensitive, receptor-positive and aromatase enzyme expressing cells, after concurrent use of letrozole and RT; with apoptosis being the primary cell death modality. This observation correlates with our findings that autophagy may have also increased (based on beclin protein levels) in these cells. It is still not clear whether letrozole treated aromatase expressing cells have a survival advantage when treated concurrently with letrozole and RT. More extensive studies are needed to be able to evaluate the effects of the concurrent use of letrozole and radiotherapy on tumor cell death.

Citation Format: Burcu Durmak Isman, Dilek Gokturk, Zeynep Sercan, Halil Ates, Zafer Karaguler, Ilknur Bilkay Gorken. Effects of Letrozole and radiotherapy on cell cycle and death in a breast cancer cell line. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1602. doi:10.1158/1538-7445.AM2013-1602

Comparing ultrasound with computerized tomography images to choose electron energy for radiotherapy boost field in breast cancer patients with breast conserving surgery

PURPOSE

To compare ultrasonographic (US) with computerized tomographic (CT) images in order to choose electron energy for radiotherapy (RT) boost field in patients with breast conserving surgery (BCS).

METHODS

Thirty-seven consecutive patients with breast cancer treated by BCS and RT in our department were evaluated. Median age was 49 years (range 32-82). According to the Dokuz Eylul Breast Tumor Group Protocol (DEBTG), in patients with BCS, RT (5000 cGy to the whole breast ± lymphatic area) and boost with electron energy to the primary tumor bed (1000 cGy if surgical margin negative, or 1600 cGy if surgical margin positive was delivered. Before January 2003, the distances between skin-the deepest point of tumor bed (STD), skin-clips (SCD), and skin-fascia (SFD) were measured with US to choose electron energy in boost field. Since then, CT simulation images were used to this purpose. These two imaging systems were compared in this study. Electron energy was selected after measurement of the deepest metallic clips in CT simulation images (90%) or measurement of the STD if no clips were present (10%).

RESULTS

Median measurements with US and CT were as follows: STD: US 12 mm (range 4-35), CT 28 mm (range 2-54); SFD: US 25 mm (range 6-57), CT 31 mm (range 2-93); SCD: US 14 mm (range 7-26), CT 29 mm (range 2-68). The median electron energy was 9 MeV é (range 6-12) for US and 12 MeV é (range 6-21) for CT. Concordance in US and CT measurements was 27%.

CONCLUSION

This preliminary study reveals that CT-based SCD measurements are deeper than US measurements, and selected electron energy with CT is 3 MeV higher than US. These two factors can affect local control and side effects. We noticed only one local recurrence in 37 patients. We did not evaluate side effects in this study. These could be a subject of a future study.

Evaluation of contralateral breast skin doses by thermoluminescent dosimeters of patients receiving adjuvant radiotherapy for breast cancer

PURPOSE

It is reported that low dose radiation received by the contralateral breast (CLB) during adjuvant radiotherapy (RT) is carcinogenic. This trial was planned to evaluate the CLB skin doses received during adjuvant RT of breast carcinoma.

PATIENTS AND METHODS

Twenty-four breast carcinoma patients treated locally or locoregionally with adjuvant RT were included. RT was performed with only tangential fields (TA) in 6 patients whereas 9 patients had an extra internal mammary (IM) field (TAIM). The remaining 9 patients received 5-field locoregional RT (5FLR). All patients were treated with wedge filters except for 3 TA patients. Of 9 5FLR patients IM fields were treated with Co60 in 5 and with electrons in the remaining 4 patients. LiF(2)-based Ribbon type thermoluminescent dosimeters (TLD) were used for dose evaluation. An average of 10 TLD's, placed with 1 cm gaps beginning from the medial border of the treatment field along the central axis were used to obtain dose measurements. Median measure of TLD's between 2-8 cm and maximum dose point (MDP) values in the same range were used to evaluate the CLB dose.

RESULTS

In TA patients the CLB skin received 6.3% of the total dose in patients treated with wedge filters and 7.13% with half-beam blocks. For 6 TAIM patients with IM fields treated with Co60, the CLB dose was 7.24%. In 5 of 9 5FLR patients, whose IM fields were treated with Co60 the CLB skin received 8.8% of the total dose, while for electron beam therapy the CLB dose was 5.44%. CLB median MDP values were as follows: 12.76% in TA patients treated with wedge filters and 11.45% with half-beam blocking; 11.89% in TAIM patients with IM fields treated with Co60 and 7.83% with electron beams; 12.29% in 5FLR patients of whose IM fields were treated with Co60 and 8.94% with electron beams.

CONCLUSION

When compared to wedge filters, halfbeam blocks caused 13% increase in CLB doses. If IM fields were added, 27.5% and 62% increases at CLB doses were established with Co60 when compared to electron beam RT in 3-field and 5-field treatments, respectively. CLB doses increased by 15-40% with the increased number of treatment fields. MDP values were also found to be higher with IM fields treated with Co60, but the number of treatment fields and accessories used seemed to have no effect on MDP doses. We conclude that by using wedge filters instead of half-beam blocks and by increasing the number of fractions treated with electron energies for IM fields, apparent decreases in CLB doses can be obtained. Large number of cases is needed to statistically establish the significant differences between subgroups.

Detection of bilateral multifocal breast cancer using Tc-99m sestamibi imaging. The role of delayed imaging

PURPOSE

Early determination that breast cancer is bilateral and multifocal can change therapy strategy and, subsequently, mortality and morbidity rates. The authors present a case with bilateral, multifocal breast cancer detected only by Tc-99m sestamibi imaging.

METHODS

Early and delayed Tc-99m sestamibi imaging and dynamic MRI were performed in a patient with a right-sided lesion shown on mammography.

RESULTS

Although early Tc-99m sestamibi imaging detected bilateral breast cancer foci, both dynamic MRI and mammography missed the lesion in the left breast. Additional lesions seen on delayed Tc-99m sestamibi images of the left breast, which were initially thought to be benign, completely disappeared after concomitant chemotherapy and radiotherapy, suggesting multifocal malignant lesions in the left breast.

CONCLUSION

This case suggests that Tc-99m sestamibi may be useful for detecting bilateral cancer, and delayed imaging may give additional information regarding the possible multifocal nature of the disease.