DNA damage and repair after exposure to sevoflurane in vivo, evaluated in Swiss albino mice by the alkaline comet assay and micronucleus test.

The relationship between DNA damage and repair of peripheral blood leukocytes, liver, kidney and brain cells was investigated in Swiss albino mice (Mus musculus L.) after exposure to sevoflurane (2.4 vol% for 2 h daily, for 3 days). Genetic damage of mouse cells was investigated by the comet assay and micronucleus test. To perform the comet assay, mice were divided into a control group and 4 groups of exposed mice sacrificed on day 3 of the experiment, at 0, 2, 6 or 24 h after the last exposure to sevoflurane. Mean tail length (TL), tail moment (TM), and tail intensity (TI) values were significantly higher in exposed mice (all examined organs) than in the control group. Significant DNA damage immediately after exposure to sevoflurane was observed in leukocytes. Damage induction in the liver, kidney, and brain occurred 6 h later than in leukocytes, as expected according to the toxicokinetics of the drug, where blood is the first compartment to absorb sevoflurane. However, none of the tested tissues revealed signs of repair until 24 h after the exposure. To distinguish the unrepaired genome damage in vivo, the micronucleus test was applied. Number of micronuclei in reticulocytes showed a statistically significant increase, as compared with the control group at all observed times after the treatment.

Brain metastases as late breast cancer relapse. Single institution experience and review of the literature.

PURPOSE: Approximately 40% of HER2-positive breast cancer patients will develop brain metastases, usually during the first 2-3 years following initial diagnosis and up to 2 years after overt metastatic spread. However, there are no data about brain metastases development as a late disease relapse. In addition, there are no data whether the high incidence of brain metastases is maintained in patients with HER2 overexpression even in late brain metastases. The aim of this paper was to determine the incidence of brain metastases and the HER2 status in patients who developed late relapse, at least 5 years after the initial diagnosis. PATIENTS AND METHODS: Among 384 consecutive breast cancer patients with late relapse, only 8 developed brain metastases. Archival pathological specimens of the primary tumors of those 8 patients were tested by immunohistochemistry (IHC) for HER2 status. RESULTS: The incidence of late brain metastases was 2% (8/384). None of these patients had HER2 3+ primary breast cancer. CONCLUSION: This study shows that the risk for brain metastases in HER2 3+ breast cancer patients is very low or might be even absent as a late relapse. Absence of late brain metastases in HER2 3+ breast cancer might be attributed to specific biological characteristics of HER2 3+ carcinomas to develop brain metastases mostly in the early course of metastatic disease.

Radiotherapy-induced changes of peripheral blood lymphocyte subpopulations in cervical cancer patients: relationship to clinical response.

PURPOSE: To determine the absolute number and percentage of peripheral blood lymphocyte subpopulations positive (+) cells CD8(+), CD8(+)NKG2D(+), CD8(+), Granzyme B(+) (GrB), CD16(+), CD16(+)NKG2D(+), CD56(+) and CD56(+)NKG2D(+) in cervical cancer patients before and after radiotherapy (RT), and to analyze whether their changes are related to the clinical response. MATERIALS AND METHODS: Stage IIB - IVA cervical cancer patients received external irradiation and concomitant intracavitary brachytherapy. Blood samples for immunophenotypic analysis by flow cytometry were collected from each patient one day before starting RT and one day after completing RT. Fifteen healthy volunteers served as controls. Surface marker expression and granzyme B positivity were quantified on FACSCalibur flow cytometer. RESULTS: Unlike their absolute numbers, the percentages of all analyzed lymphocyte subsets of all patients, including those with complete response (CR), were significantly increased (p <0.05) after RT. Only in patients with progressive disease (PD), CD8(+), CD8(+)NKG2D(+), CD16(+) and CD56(+)NKG2D(+) lymphocytes were not significantly increased. In healthy volunteers, the percentage of CD8(+)GrB(+) lymphocytes was lower than in patients after RT, while the percentages of CD56(+) and CD56(+)NKG2D(+) cells were higher than in patients before RT (p <0.05). CONCLUSION: Our data indicate that RT, besides its direct cytoreductive effect on tumor cells, may contribute to better immunological control of cervical cancer.

[Pediatric brain tumors--diagnostic and treatment].

During the period 1995-2004 we treated 212 patients (pts) with brain tumors. There were 133 boys and 79 girls, aged from 2,5 yrs up to 18 yrs (Me = 9, 7 yrs). The majority of pts were in age group (4-16) yrs-179 pts. Supratentorial tumors were diagnosed in 118 pts vs. infratentorial 94 pts. Therapy involved surgery, postoperative radiotherapy with or without chemotherapy. Survival rates were calculated using Caplan-Meier method and differences between curves with log-rank test. During the follow-up period from 1 to 9 year (Me = 3 yrs) 5-year disease free survival rate was 55.7%. 79 pts failed to therapy. There was no statistically significant difference in survival according to sex (p = 0.123) and age (p = 0.367). Pts with supratentorial tumors had statistically significant better survival (p = 0.036). Pts with histologic type low grade astrocitomas had statistically significant better survival than malignant gliomas, ependymomas and PNET (p = 0.0001). Surgery, postoperative radiotherapy and chemotherapy in selected cases are efficient therapeutic approach for pediatric brain tumors.

[Diagnosis of breast cancer in women age 40 and younger: mammography and breast ultrasound].

Breast cancer is the leading cause of mortality among women aged 25 to 44 years in Serbia. The purpose of this study was to determine basic clinical and radiological features of breast cancer in young women. 93 women aged 31.0 +/- 3.5 years with breast cancer were identified. The analysis included clinical characteristics (TNM classification) and radiological features (mammography and breast ultrasound). 53.8% of the patients had locoregional disease. The mean diameter of breast cancer was 2.6 +/- 6 cm. Carcinoma in situ was found in 2.2%. Mammography was performed in 25.8% of the patients and breast ultrasound in 68.8%. The results of our study indicate that the diagnosis of breast cancer in young women is late, in the stage with palpable breast tumor and lymph node metastases. Mammography or breast ultrasound are not routinely used. The implementation of algorithms for breast cancer detection and diagnosis in young women helps in earlier detection of breast cancer and consequently improves outcomes.

[Combined hormono-radiotherapy in treatment of locally advanced prostate cancer].

Numerous questions regarding combined hormono-radiotherapy in the treatment of locally advanced prostate cancer still remain open. We present results of combined treatment in 133 our patients with locally advanced prostate cancer. All patients recieved hormonotherapy as neoadjuvant, concomitant with radiotherapy (tumor dose range 65-72 Gy), and adjuvant. In six months follow-up time, complete regression (CR) was noted in 120 patients (90%), partial regression (PR) in 6 (4.5%), stabile disease (SD) in 2 (1.5%) and progression of disease (PD) in 5 patients (4%). In mean follow up time of 17 months (6-77), 13 patients relapsed. Five-year time to progression was 70%. Five-year disease-free interval for CR patients was 70%. At the date of last control CR was noted in 116 patients (87%), PR in 2 patients (2%), SD in 7 patients (5%), and 8 patients (6%) had progressive disease. Second malignancy was noted in 4 patients. Multidisciplinary studies directed towards the optimisation of combined treatment are ongoing. There are no definitive conclusions.

[Postoperative radiotherapy of cervival carcinoma: treatment results and analysis of prognostic factors].

The purpose of the study was to evaluate the efficacy of postoperative radiotherapy (RT) and to investigate prognostic factors for early-stage cervical cancer patients. We reviewed the medical records of 162 cervical cancer patients treated by RT during 2003 year. RT included 30-45 Gy of external photons to pelvis in 12-25 fractions. Brachytherapy with 192Ir was delivered in 3-5 fractions to a dose of 27-32 Gy. The mean age was 49 years (range 27-71). Majority of patients 130 had Stage Ib. Radical hysterectomy with lymphadenectomy was performed in 122 pts. and simple hysterectomy in 40 pts. The 5-year actuarial overall survival (OS) for all patients was 92.6% and disease-free survival (DFS) was 90.9%.There was statistically significant differences in OS and DFS in pat. with positive vs. negative pelvic lymph nodes; tumor 4 cm vs. tumor < or = 4 cm; positive vs. negative surgical margin/residual tumor (p < 0.05). Late GIT complications were determined in 35.8% and UT in 12.3%. In conclusion, postoperative radiotherapy has achieved high-satisfactory survival with acceptable complications. The survival benefit was less evident among patients with positive lymph nodes, tumor > 4 cm and positive surgical margin/residual tumor.

[Implementation of 3D- CT based brachytherapy in the postoperative radiotherapy of cervical cancer: treatment technique and dose-volume parameters].

Intracavitary brachytherapy has an important roll in developing complications in postoperative radiotherapy of cervical cancer. 3D- CT based brachytherapy gives precisely estimating doses to organ at risk. In this study, we show our preliminary results in implementation of 3D-imaging based postoperative brachytherapy of cervical cancer: treatment technique and dose-volume parameters. During 2009 year, in 6 patients with early stage I-II of cervical cancer, brachytherapy treatment planning was based on the radiographs and CT imaging brachytherapy technique. Mean values of ICRU reference points of rectum was R max 4,2 Gy and bladder B max 4,5 Gy, while estimated volume-dose parameters D0.1 cm3 D1.0 cm D2.0 cm3 were presented with higher dose.Volume of organ at risk reflected the need for better bladder preparation. Our initial experience in performing CT-based brachytherapy, enabled us to introduce the characteristics of the parameters, assessment of their significance from the aspect of mutual relations applicators and organs at risk. Further analysis are needed, for monitoring the effects of 3D planning on complications.

TP53 mutations in breast cancer: association with ductal histology and early relapse of disease.

PURPOSE: This study aimed to investigate the incidence of core domain TP53 mutations in Serbian breast cancer patients in view of their possible correlation with prognostic parameters, tumor characteristics and clinical disease course. METHODS: 145 breast cancer patients were included. Data on clinical disease course were available for 100 patients including 30 node-negative and 70 node-positive patients. After surgery, node-positive patients underwent adjuvant chemotherapy, mostly CMF. TP53 mutations were detected by PCR-SSCP. RESULTS: 31 mutations were found in 27/145 patients including 4/59 node-negative patients and 23/83 node-positive patients (4 double mutations). 26/31 TP53 mutations were found in patients with invasive ductal carcinoma and only 2 in patients with invasive lobular carcinoma. The presence of TP53 mutations was correlated with clinical disease course in premenopausal node-positive patients (n=70). 11/20 patients with TP53 mutations relapsed. Within the first 24 months of follow-up, significantly shorter disease-free intervals were observed in TP53-mutated patients. CONCLUSIONS: TP53 mutations correlated only with nodal status and ductal histology. The significance of the predominant distribution of TP53 mutations in tumors with a ductal histology for the aggressive behavior of these tumors has yet to be proved, since the favorable biological features of tumors with a lobular histology do not result in a better prognosis. Early relapse in mutated-TP53 carriers may support data on its predictive value with respect to adjuvant CMF.

Biweekly oxaliplatin, fluorouracil and leucovorin versus cisplatin, fluorouracil and leucovorin in patients with advanced gastric cancer.

PURPOSE: To compare a bi-weekly infusion of leucovorin (LV) 5-fluorouracil (5-FU) for 2 days, plus oxaliplatin (LV5- FU2-oxaliplatin) and LV5-FU2-cisplatin (CDDP) regimens with respect to toxicity, objective response rates, time to progression (TTP) and overall survival (OS) in patients with advanced gastric cancer. PATIENTS AND METHODS: Patients received LV5-FU2- oxaliplatin (oxaliplatin 85 mg/m(2), day 1; folinic acid 200 mg/m(2), days 1-2; 5-FU 400 mg/m(2), i.v. bolus, days 1-2; 5-FU 600 mg/m(2), 22-hour continuous infusion, days 1-2) or LV5- FU2-CDDP (CDDP 50 mg/m(2), day 1; plus LV5-FU2). A total of 72 patients were enrolled into this study (36 vs. 36). RESULTS: A total of 305 cycles were administered in the LV5-FU2-oxaliplatin arm (median 8) and 272 cycles in the LV5-FU2-CDDP arm (median 8). Grades 3-4 toxicity were as follows (LV5-FU2-oxaliplatin %/LV5-FU2-CDDP %; p<0.05): neutropenia 5/49, thrombocytopenia 2/6, anemia 6/16 nausea/vomiting 2/15, and mucositis 0/3. Response rate of LV5-FU2-oxaliplatin was 41% (partial response/PR 41%, stable disease/SD 31%, progressive disease/PD 28%; 95% confidence internal/95% CI 27-58) and of LV5-FU2-CDDP was 25% (PR 25%, SD 36%, PD 39%; 95% CI 14-41; p =0.013). The median TTP of the patients in the LV5-FU2-oxaliplatin arm was 8 months and 6 months for those in the LV5- FU2-CDDP arm (p=0.073). The median survival time of the patients in the LV5-FU2-oxaliplatin arm was 10 months and 7 months for those in the LV5-FU2-CDDP arm (p=0.003). CONCLUSION: Our study showed that oxaliplatin may be substituted for cisplatin with LV5-FU2 with favorable safety and efficacy profile. The encouraging results from our study support the effectiveness of oxaliplatin-fluoropyrimidine- containing chemotherapy in gastric cancer and could provide a new core on which to add other agents in future investigations.

Risk factors for breast cancer: is ionizing radiation among them?

All human beings are exposed to the influence of ionizing radiation from natural, medical and other artificial sources. Therefore, the influence of radiation as a risk factor for cancer development has been among the most studied external factors over the last 6 decades, particularly with respect to radiosensitive tissues and organs. It has been known that female breast tissue is highly sensitive to the carcinogenic effects of radiation, particularly when exposure takes place at younger age. All women are exposed to low doses of radiation for several common reasons (kind of occupation, medical diagnostic procedures, residence background radiation) whose effects on breast cancer development cannot be documented, and thus it is believed that ionizing radiation is not primary or major risk factor leading to development of breast cancer. Radiobiological studies revealed a specific event caused by radiation through recognition of the critical target in radiation-induced carcinogenesis. Accordingly, mutagenic and carcinogenic effects of ionizing radiation are evidenced both in vitro and in vivo, although the incidence of radiation-induced cancers is low. The highest risk of radiation- induced breast cancer is evidenced in the sub-population of female patients who have undergone radiotherapy for either malignant or non-malignant diseases, including benign breast diseases in their childhood or young age. Therefore, as a means of prevention in this group of population, indications for application of ionizing radiation, both diagnostic and therapeutic, should be highly selective, meaning that radiation should be applied only if the possible benefit outweighs the risk.

[Mammography in detection clinically occult breast carcinoma].

AIM: The significance of mammography in detection of nonpalpable breast cancer MATERIAL AND METHODS: This prospective study was conducted at the Institute for oncology and radiology of Serbia in Belgrade. It involved 198 asymptomatic women with performed screening mammography, 154 specimen mammography, out of wich 38 had stereotaxic mark, "ex tempore" biopsy, while 44 women had "ex tempore" biopsy and adequate surgery. RESULTS: Screening mammography revealed suspect microcalcifications in 148 cases, impaired structural tissue in 59 and focal condensation in 55 cases. Histologic examination verified breast carcinoma in 80 patients with very statistical significance of ductal type, especially comedo subvariant (p < 0.001). Pleomorphic microcalcifications smaller than 0.5 mm of grouped or segmented form are statistically very significant for malignity (p < 0.001) as well as associated microcalcifications with altered architectony and focal tissue condensation (p < 0.001). CONCLUSION: Mammography has great significance in detection of occult breast carcinoma which are not only preinvasive, but olso microinvasive and invasive. This fact leads to the neccesity of introduction of legal obligation for mammography screening, especially for women aged between 50 and 70 years.

Postmastectomy radiotherapy in intermediate risk stage I-II breast cancer patients.

PURPOSE: To evaluate the correlation of postmastectomy radiotherapy (PMRT) with local relapse rate, disease-free survival (DFS) and overall survival (OS) in a group of breast cancer (BC) patients at intermediate risk for locoregional relapse (stage I-II with either 1-3 positive axillary nodes, or node-negative grade III BC) treated with radical mastectomy. PATIENTS AND METHODS: We evaluated 482 stage I-II BC patients, with either node-negative grade 3 tumors or with 1-3 positive nodes irrespective of tumor grade, treated with radical mastectomy at our Institute from 1986 to 1994. After mastectomy they received either adjuvant CMF (cyclophosphamide, methotrexate, 5-fluorouracil) chemotherapy (N=172), or adjuvant endocrine therapy (N=310). Postoperative radiotherapy (RT group) to the regional lymph nodes with tumor dose (TD) 48 Gy in 22 fractions was delivered to 199 patients. RESULTS: After a median follow-up of 79.5 months, no difference in relapse rate between the two groups was seen (30.6% in the RT group vs. 36.7% in the no RT group; x(2), p=0.1). Local recurrence rate occurring alone or with distant metastases was 4.52% in the RT group vs. 7.77% in the no RT group (x(2), p=0.1). However, local recurrence rate alone was significantly higher in the RT group compared to the no RT group (2.01 vs. 6.01%, x(2), p=0.041). In premenopausal patients local relapses occurred in 3.2% of patients with postoperative RT and in 8.2% in patients without RT (Fisher's exact test, p=0.48). Non significant difference was registered in postmenopausal patients with (4.76%) or without RT (6.58%). Ten-year DFS and OS were 53.5% and 68.7% in the RT group vs. 52.9% and 75.2% in the no RT group (non significant difference). CONCLUSION: Our results did not show that PMRT significantly influences the incidence of disease relapse, DFS and OS in stage I-II BC patients with intermediate risk for disease relapse. However, it seems that PMRT might influence the occurrence of locoregional recurrence in these patients.

Incomplete operative removal of colorectal liver metastases followed by chemotherapy decreases survival in comparison to chemotherapy alone.

Metastatic colorectal carcinoma (CRC) has an inevitable fatal outcome except in a small percentage of selected patients, approximately 10-20%, with good prognosis after successful complete operative removal of the liver metastases. In patients not eligible for surgical resection of the liver metastases, chemotherapy is currently the only widely available treatment option. Controversy still exists about the criteria for operability of CRC liver metastases, and some patients, still undergo ineffective, i.e. unnecessary surgery. The aim of this paper is to analyse and compare the overall survival (OS) and time to progression (TTP) in patients who underwent incomplete removal of liver CRC metastases followed by chemotherapy, and patients treated with chemotherapy alone. Seventy-three patients with CRC liver metastases underwent incomplete operative removal of the metastases followed by FOLFIRI (Cohort A - 27 patients) or with FOLFIRI alone (Cohort B - 46 patients). Patients received FOLFIRI until progression. FOLFOX4 was used as second line chemotherapy. The median OS in Cohort A was 8 months, the median TTP was 5 months, and the response rate was 44%; the median OS in Cohort B was 19 months, the median TTP was 8m, and the response rate was 39%. There was a significant difference in OS and in TTP (p < 0.01) in favour of the chemotherapy alone group (B). Patients undergoing incomplete removal of the liver metastases had shorter survival and TTP in comparison with patients treated with chemotherapy alone.

Effects of X-ray irradiation on the overexpression of HER-2/Erb-B2 on breast cancer cell lines.

Irradiation is the conventional treatment modality for cancer patients. However, besides its cytotoxic effects on malignant cells it might also affect the biology of surviving cells. Since overexpression of HER-2 receptors on malignant cells is a prerequisite for the therapeutic efficacy of Herceptin, it seems important to know whether previous irradiation changes their overexpression. The experiments performed in this work were aimed to determine whether X-ray irradiation of MDA-MB-361 and MDA-MB-453 breast carcinoma cell lines, besides its cytotoxic action, affects the overexpression of HER-2 protein. Determination of the cytotoxic effect of X-ray irradiation was done using trypan blue test. The breast carcinoma cell responsiveness to herceptin treatment in the presence of 10% fresh human serum (from healthy volunteer's) in the presence or absence of 25 microg/ml of herceptin, in vitro before and after cell-irradiation, was evaluated by MTT test. The degree of HER-2 overexpression was determined by immunocytochemistry, using DAKO HercepTest. Preliminary results obtained in this work showed that X-ray irradiation, besides its cytotoxic effect on malignant cells, could lead to overexpression of HER-2 receptors on (initially by immunocytochemistry, HER-2 negative) tumor cells, indicating change in biology of treated tumor cells. Further investigation in this direction will probably be helpful to elucidate this task in order to improve the selection of irradiated patients for Herceptin therapy.

[Medullary carcinoma of the thyroid gland: effect of postoperative transcutaneous radiotherapy on local control and results of treatment]. / Medularni karcinom stitaste zlezde: uticaj postoperativne transkutane zracne terapije u lokalnoj kontroli i rezultatima lecenja.

In the period of Octo. 01, 1987. up to Dec. 31, 1998. retrospective-prospective, non-randomized study was conducted at IORS, which included 36 patients diagnosed with thyroid gland medullar cancer. Our study had the following aims: evaluation of treatment results following probability of total survival, survival without signs of disease and disease-free interval until local recurrence of the disease and influence of parameters of transcutaneous radiotherapy (intensity of total tumor dose and length of disease-free interval from date of performed operation to beginning of radiotherapy). After finished treatment, median of the patient follow-up was 37.75 months (3.5 up to 141 months); probability of total five-year survival was 62.61% and of 10 year survival was 23.48%. Probability of 5-year survival, without signs of disease was 37.13%, and of 10-year survival 18.56%. As to radiotherapy parameters intensity of total therapy dose was statistically insignificant, while time interval to beginning of transcutaneous radiotherapy, shorter than 2 months, was statistically significant in relation to prognosis of disease outcome.

[Radiotherapy in malignant tumors of the thyroid gland]. / Radioterapija malignih tumora stitaste zlezde.

The primary treatment of thyroid gland malignoma is surgery. Success of radiotherapy depends of extent of the previous surgery treatment. The types of radiotherapy are: curative (prophylactic and postoperative) and palliative. Tumor dose and radiotherapy tehnique depend on histologica type, extent of the previous surgery treatment, curative or paliative intent and general condition of patient, and they are from 40 Gy to 65 Gy by conventional fractionation. The basis of radiotherapy treatment planning and choice of radiotherapy treatment technique in survey of the region of interest by imaging procedure. On the basis of those data we determine therapeutic volume and structure of risk (spinal cord, lung) and protection of the risky structures is planned.

Combined chemoradiotherapy in the treatment of locally advanced non-small cell lung cancer.

PURPOSE: To evaluate prospectively the combination of radiotherapy with low doses of carboplatin given as radiosensitizer in patients with locally advanced non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients enrolled in this trial were randomly allocated in two groups. The study group consisted of 67 patients with stage IIIA/B NSCLC who were treated initially with a tumor dose (TD) of 30 Gy in 10 fractions, 5 fractions per weeks, in 2 weeks. Carboplatin was administered simultaneously as radiosensitizer at a dose of 20 mg/m(2) i.v. bolus just prior to each radiotherapy fraction. After a 2-week rest an additional 25 Gy were given in 10 fractions, with carboplatin as previously described. The total tumor dose (TTD) was 55 Gy (30+25 Gy) in 20 fractions in 6 weeks and the total dose of carboplatin was 600 mg. The study group was compared with a control group of 70 NSCLC patients who were treated with radical conventional radiotherapy (60 Gy in 30 fractions, 2 Gy per fraction, 5 fractions per week). RESULTS: Haematological toxicity and oesophagitis were statistically more often seen in the study group. There was no statistically significant difference in the response rate between the 2 groups (53.7% versus 62.8%). The 2-year survival was 27% in the study group and 33% in the control group (p >0.05). CONCLUSION: The results showed no response and survival benefit of concomitant chemoradiotherapy compared with conventional radiotherapy. We believe that further prospective, multicenter trials are required to evaluate the concurrent combination of new cytotoxic agents used as radiosensitizers with conventional radiotherapy or radiotherapy with different fractionation schedules and high-technology equipment which enables the application of higher tumor doses.