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Adherence to clinical practice guidelines improves outcomes for patients with breast cancer. However, their implementation may not be feasible in low- and middle-income countries. This study aimed to evaluate physicians' adherence, attitudes, and barriers towards the Colima Consensus, which is the Mexican national breast cancer clinical practice guideline.A cross-sectional, 31-item survey was e-mailed to Consensus attendees and members of the Mexican Society of Oncology and Mexican Mastology Association. Descriptive statistics, univariate, and multivariate analysis were used to analyze the associations between participants' characteristics, adherence, attitudes, and barriers.Of 439 respondents, 78% percent adhered to Consensus recommendations and 94% believed it was applicable to their clinical practice. Forty percent reported using the Consensus as their sole breast cancer guideline. This was associated with being a surgical oncologist (OR 3.3, 95% CI 2.0-5.3) and practicing at a public hospital (OR 2.1, 95% CI 1.2-3.7). The most common barriers to adherence were lack of resources and logistical problems. Regarding attitudes towards the Consensus, 90% considered it a good educational tool, 89% considered it a reliable source of information, and 90% thought it improved quality of care.We showed high levels of adherence and positive attitudes towards the Colima Consensus, with a significant proportion of physicians using it as their only guideline. Lack of resources and logistical issues were the main barriers to adherence. Our results highlight the relevance of local breast cancer guidelines and suggest a need for the creation of resource-stratified guidelines.

Purpose The safety and effectiveness of moderately hypofractionated post-operative radiation therapy for breast cancer were demonstrated by several trials. This study aimed to evaluate the current patterns of practice and to assess possible aspects that affect the decision-making process regarding the use of fractionation in breast cancer patients in Latin America and the Caribbean (LAC). Methods Radiation oncologists from LAC were invited to contribute to this this study. A 38-question survey was used to evaluate their opinions. Results A total of 173 radiation oncologists from 13 countries answered the questionnaire. The majority of respondents (84.9%) preferred moderately hypofractionated post-operative radiation therapy as their first choice in cases of whole breast irradiation. For whole breast plus regional nodal irradiation, post-mastectomy (chest wall and regional nodal irradiation) without reconstruction, and post-mastectomy (chest wall and regional node irradiation) with reconstruction hypofractionated post-operative radiation therapy was preferred by 72.2% 71.1%, and 53.7% of respondents, respectively. Breast cancer stage, and flap-based breast reconstruction were the factors associated with absolute contraindications for the use of hypofractionated schedules. Conclusion Even though moderately hypofractionated post-operative radiation therapy for breast cancer is considered a new standard to the vast majority of the patients, its unrestricted application in clinical practice across LAC still faces reluctance.

PURPOSE To measure the out-of-field mean photon energy and dose imparted by the secondary radiation field generated by 6 MV and 6 MV FFF beams using TLD-300 and TLD-100 dosimeters and to use the technique to quantify the contributions from the different sources that generate out-of-field radiation. METHODS The mean photon energy and the dose were measured using the TLD-300 glow curve properties and the TLD-100 response, respectively. The TLD-300 glow curve shape was energy-calibrated with gamma rays from 99m Tc, 18 F, 137 Cs, and 60 Co sources, and its energy dependence was quantified by a parameter obtained from the curve deconvolution. The TLD-100 signal was calibrated in absorbed dose-to-water inside the primary field. Dosimeters were placed on the linac head, and on the surface and at 4.5 cm depth in PMMA at 1-15 cm lateral distances from a 10 × 10 cm2 field edge at the isocenter plane. Three configurations of dosimeters around the linac were defined to identify and quantify the contributions from the different sources of out-of-field radiation. RESULTS Typical energies of head leakage were about 500 keV for both beams. The mean energy of collimator-scattered radiation was equal to or larger than 1250 keV and, for phantom-scattered radiation, mean photon energies were 400 keV for the 6 MV and 300 keV for the 6 MV FFF beam. Relative uncertainties to determine mean photon energy were better than 15% for energies below 700 keV, and 40% above 1000 keV. The technique lost its sensitivity to the incident photon energy above 1250 keV. On the phantom surface and at 1-15 cm from the field edge, 80%-90% of out-of-field dose came from scattering in the secondary collimator. At 4.5 cm deep in the phantom and 1-5 cm from the field edge, 50%-60% of the out-of-field dose originated in the phantom. At the points of measurement, the head leakage imparted less than 0.1% of the dose at the isocenter. The 6 MV FFF beam imparted 8-36% less out-of-field dose than the 6 MV beam. These energy results are consistent with general Monte Carlo simulation predictions and show excellent agreement with simulations for a similar linac. The measured out-of-field doses showed good agreement with independent evaluations. CONCLUSIONS The out-of-field mean photon energy and dose imparted by the secondary radiation field were quantified by the applied TLD-300/TLD-100 method. The main sources of out-of-field dose were identified and quantified using three configurations of dosimeters around the linac. This technique could be of value to validate Monte Carlo simulations where the linac head design, configuration, or material composition are unavailable.

AIM: To compare the dose to organs at risk with free breathing (FB) or voluntary breath-hold (VBH) during radiotherapy of patients with left sided breast cancer. BACKGROUND: Radiotherapy reduces the risk of breast-cancer-specific mortality but the effects on other organs increase non-cancer-specific mortality. Radiation exposure to the heart, in particular in patients with left sided breast cancer, can be reduced by breath hold methods that increase the distance between the heart and the radiation field. MATERIALS AND METHODS: Three-dimensional conformal radiotherapy (3D-CRT) dose plans for the left breast and organs at risk including the heart, left anterior descending coronary artery (LAD) and ipsilateral lung were compared with FB and VBH in ten patients with left sided breast cancer. RESULTS: The mean doses to the heart and LAD were reduced by 50.4 % (p

Aim Describe the anatomical changes and tumor displacement due to a rapid response of a patient’s small cell lung cancer (SCLC) during definitive chemoradiotherapy (CRT). Background The treatment for SCLC is based on CRT. If interfractional changes during RT are incorrectly assessed they might compromise adequate coverage of the tumor or increase dose to organs at risk. Image guided RT with cone-beam computed tomography (CBCT) allows to identify daily treatment variations. Material and methods Describe a SCLC case with rapid changes in size, shape and location of the primary tumor during RT. Case report A 62-year-old woman was diagnosed with SCLC with complete obstruction of the anterior and lingular bronchi and incomplete left thorax expansion due to a 12 × 15 cm mass. During CRT (45 Gy in 1.5 Gy per fraction, twice daily) the patient presented rapid tumor response, leading to resolution of bronchi obstruction and hemithorax expansion. Tumor shifted up to 4 cm from its original position. The identification of variations led to two new simulations and planning in a 3-week treatment course. Conclusions The complete radiological response was possible due to systematic monitoring of the tumor during CRT. We recommend frequent on-site image verification. Daily CBCT should be considered with pretreatment tumor obstruction, pleural effusion, atelectasis, large volumes or radiosensitive histology that might resolve early and rapidly and could lead to a miss of the tumor or increased toxicity. Further research should be made in replanning effect in coverage of microscopic disease since it increases uncertainty in this scenario.

The current standard of care for locally advanced cervical cancer is whole pelvis and para-aortic radiation when indicated, delivered concomitantly with chemotherapy and brachytherapy. Para-aortic node involvement is a predictor of survival in locally advanced disease but presence of metastases is difficult to determine because the currently available imaging methods lack enough sensitivity to be able to detect accurately para-aortic metastases when surgical staging is not feasible. The objective of this review is to describe the current status of para-aortic lymph node irradiation in locally advanced cervical cancer. It includes analysis of the diagnostic imaging and surgical approaches for assessment of para-aortic lymph node dissemination, together with indications for radiotherapy and radiotherapeutic techniques.

In recent years, the treatment of locally-advanced and metastatic cervical cancer has improved greatly due to the introduction of targeted therapies, new chemotherapy combinations, and emerging treatments. Candidates for potentially curative treatment are those patients with good functional status without associated comorbidities. Numerous trials have demonstrated that chemotherapy prolongs survival versus supportive care alone. In addition, polychemotherapy schemes are superior to single agent regimens. Targeted molecular agents have proven beneficial in the treatment of cervical cancer. Second-line treatment should be considered standard practice in patients with good functional status. Finally, given the poor survival outcomes in patients with metastatic disease, participation in clinical studies should always be considered the best option.

AIM: To evaluate the dose distribution to the left anterior descending (LAD) coronary artery in patients treated with postoperative three-dimensional conformal radiotherapy (3DCRT). BACKGROUND: Postoperative radiotherapy may increase the risk of heart disease, particularly in patients with left-sided breast cancer. Clinical data on doses to the LAD are limited. MATERIALS AND METHODS: Retrospective study of 14 patients who underwent postoperative 3DCRT for left breast cancer in 2014. All data were retrieved from medical records. Means, medians, ranges, and percentages were calculated. RESULTS: The mean dose to the LAD in patients with V25

Background and Aims Although the latent membrane protein type 1 (LMP1) is frequently expressed in Epstein-Barr virus (EBV) malignancies, its contribution to the pathogenesis of nasopharyngeal carcinoma (NPC) is not fully defined. LMP1 functions as a viral mimic of the TNFR family member engaging a number of signaling pathways that induce morphological and phenotypic alterations. This study aimed to investigate the LMP1 expression and EBV infection in relation to clinical outcome and survival in a series of Mexican NPC patients. We also studied expression of p16 and p53 proteins. Methods We analyzed in 25 tumor specimens the expression of LMP1, p16 and p53 by immunohistochemistry (IHC) and EBV presence by IHC/in situ hybridization. Differences in clinical outcome and survival in relation to protein expression were correlated through χ 2 statistics and Kaplan-Meier survival curves. Results Our results showed a rate of 92% (23/25) of EBV infection. The expressions of LMP-1, p16 and p53 proteins were 40.0, 44.0 and 40.0%, respectively. LMP-1 immunoexpression was more common in older patients (>50 vs. p = 0.02) and with parapharyngeal space invasion ( p = 0.02). The presence of metastatic disease at diagnosis ( p = 0.03), distant recurrence disease ( p = 0.006) and shorter distance recurrence-free survival ( p = 0.05) was associated with lack of p16. Conclusions In our series, EBV infection rates are particularly high for nonendemic NPC, although without a statistically significant difference in overall survival, LMP1 and p16 expression was correlated with poorer clinical prognosis. Probably, LMP1 and p16 detection identify a worse clinical prognosis in NPC patient subgroup.

Glioblastoma multiforme is one of the most aggressive central nervous system tumors and with worse prognosis. Until now,treatments have managed to significantly increase the survival of these patients, depending on age, cognitive status, and autonomy of the individuals themselves. Based on these parameters, both initial or recurrence treatments are performed, as well as monitoring of disease by imaging studies. When the patient enters the terminal phase and curative treatments are suspended, respect for the previous wishes of the patient and development and implementation of palliative therapies must be guaranteed.

Nearly 60% of breast cancer cases in Mexico are in advanced stages. At our institution, concomitant preoperative chemoradiation is being used in patients with advanced breast cancer. In the present study, we evaluated the postoperative wound complications and risk factors associated.The study included breast cancer patients from January 2000 to December 2002 treated with concomitant preoperative chemoradiation and mastectomy. Wound complication rates were described along with a nested case-control analysis to evaluate risk factors for postoperative major wound complications.We evaluated 360 patients treated with preoperative chemoradiation. About 165 patients (45.8%) developed a wound complication (infection and/or flap necrosis); 60 (16.6%) patients had a surgical site infection (SSI) and 61 (16.9%), flap necrosis; 44 (12.2%) developed both complications, and 25 (6.9%) experienced late dehiscence after suture removal. Epidermolysis, seroma, and hematoma occurred in 93 (25.8%), 80 (22.2%), and 12 patients (3.3%), respectively. Case-control analysis was conducted in 335 patients. After logistic regression analysis, the sole variable found associated with SSI and/or flap necrosis was epidermolysis (OR = 8.81, 95% CI = 4.52-17.18). Although not significant and of lesser magnitude, adjusted risk estimates of overweight, age50 years, and type of mastectomy showed the same trend.Postoperative wound complications were not different from those observed in non-radiated patients, but its rate was higher. Epidermolysis was associated with SSI and/or flap necrosis. Careful surgical technique should be encouraged.

Advanced squamous cell skin carcinoma of the head & neck represents a therapeutic challenge and the purpose of the present study was to identify factors related to disease recurrence and survival. Clinical case records of 104 patients were reviewed. Tumours were located in scalp (28%), nose (23%), cheek (19%), ear (17%) and eyelids (12%). Of the tumours, 57% were >2cm and lymph node metastases were present in 12%. Treatment administered was surgery (46%), radiotherapy (35%). Surgery + radiotherapy (16%) and chemo-radiotherapy (3%). Most relapses were local (23%). Positive margin was associated with lower recurrence (7% vs 37%; p=0.047). Mortality was associated with tumour size >4 cm (p=0.020); scalp, cheek and ear location (p=0.025); deep penetration (p=0.005); single-modality of treatment (p=0.021). Patients with large tumours (>4 cm) located in scalp, cheek and ear together with deep penetration and with positive margins need to be treated aggressively.

El objetivo del estudio fue evaluar la respuesta de la pilocarpina en la xerostomía inducida por radioterapia en cabeza y cuello. El diseño de estudio fue descriptivo, prospectivo de corte longitudinal, doble ciego. Los pacientes se distribuyeron aleatoriamente en dos grupos. El grupo 1 (n = 10) de control recibió placebo. Al grupo 2 (n = 10) de estudio se le administró 5 mg diarios de pilocarpina cada 8 h por vía oral. Se realizaron tres cuantificaciones del flujo salival; al inicio del tratamiento, a la quinta y a la séptima semana, por el método de diferenciación de pesos. En la primera cuantificación, al inicio del tratamiento de radioterapia, los pacientes no habían recibido ningún tipo de medicamento, en ningún grupo. Comparando ambos grupos se obtuvo t = 0.525, P = 0.606, por lo que no existía diferencia estadísticamente significativa, en el flujo salival. A la quinta semana se observó en ambos grupos disminución del flujo salival, comparándolos se obtuvo t = 0.481, P = 0.636, por lo que no se encontró diferencia estadísticamente significativa. Sin embargo, el grupo de estudiotuvo un incremento estadísticamente significativo a la séptima semana , del flujo salival, donde se obtuvo una media 0.651 y d.s 0.380, mientras el grupo control mostró una media 0.256, d.s 0.251 al aplicar una t de Student se obtuvo t = 2.743, P = de 0.013. Concluyendo que la pilocarpina es un tratamiento alternativo, viable, seguro y económico, para la xerostomía inducida por radioterapia.

Ulcers in radiated skin continue to be a challenge for health care practitioners. Healing impairment in the setting of radiation-damaged tissue will most of the time lead to chronic wounds that reduce the patient's quality of life. In this review, we present an update of the pathophysiology of tissue damage caused by radiation that leads to chronic ulceration. We also explore the evidence available on the different prevention and treatment modalities that have been reported in the literature. The evidence for most preventive measures is inconclusive; however, sucralfate and amifostine seem to be the adequate recommendations for prophylaxis. As for treatment of ulcerated patients, the strongest level of evidence found was for the use of pentoxifylline, but proper trials are still scarce to be considered standard adjuvant therapy. Hyperbaric oxygen, cytokines and other growth factors and surgical interventions have shown some benefit in case reports and case series only. Other therapies show promise based on their mechanism of action but need to be tested in human studies and clinical trials.

Malignant sinunasal tumors are very rare in Mexico. They ussually present as advanced disease because it is extremely difficult to make an early diagnosis; in addition, its treatment is complicated by a variety of lesions. Surgical resection remains the mainstay of treatment, but its relative therapeutic value compared with alternative treatments is controversial. We undertook a retrospective analysis in order to evaluate results of craniofacial resections for sinunasal tumors. A total of 20 patients, 11 men and 9 women were considered, median age was 49 years (18–74). Eleven had received previous treatment elsewhere. In 13 patients tumor was limited to maxilo-etmoidal complex, but in 6 cases tumor involved anteroinferior aspect of esfenoidal sinus, in 7 extended to the orbit, in 3 to dura and two to the brain. One had cervical metastases. Median tumoral size was 5.8 cm (1–10). Overall complication rate was 50%. Major surgical complications occurred in 4 patients (20%): one patient developed isolated cerebrobrpinal fluid leakage (CEFL), 1 developed deterioration of mental status, and two developed meningitis associated with CEFL. Late complications occurred in 30% of the patients. There was not any operative death. Eleven patients received postoperative radiotherapy. Fifteen patients recurred. There were 11 local relapses, although one associated with a regional relapse, and another with regional and distant relapse. There were four isolated regional fails and six isolated distant failures. Three year overall survival was 65%, and 3-year disease free survival was 50%. Patients without previous treatment median survival was 28.3 months, meanwhile with previous treatment was 18.2 months. Craniofacial resection is a safe and valuable tool in the treatment of advanced sinunasal tumors involving cranial base.

Osteosarcoma is an infrequent, locally aggressive neoplasm in the head and neck region. To date, surgery is the mainstay of treatment. However, patients with mandibular osteosarcomas usually have a locally advanced disease at diagnosis and therefore represent a therapeutic challenge because surgical margins are difficult to obtain due to aesthetic and functional concerns. To evaluate possible prognostic factors implicated in recurrence, persistence or relapse in osteosarcoma of the mandible, with special reference to the soft tissue and bone surgical margins. A series of 20 patients with mandibular osteosarcomas treated at the Instituto Nacional de Cancerologia (Mexico) from 1985 to 1999 are reviewed. There were 14 female and 6 male patients. Twelve cases were treated with surgery alone, 3 patients with surgery and adjuvant radiotherapy, 1 had neoadjuvant chemotherapy followed by surgery, 1 had neoadjuvant chemotherapy, surgery and postoperative radiotherapy, 1 with surgery and adjuvant chemotherapy, 1 with surgery followed by adjuvant chemotherapy and radiotherapy and one patient rejected treatment. Between 1985 and 1992 these neoplasms were treated by means of total mandibulectomy, independently of tumor size, but between 1993 and 1999 the policy was to practice smaller resections but long enough to obtain macroscopic surgical free margins. In the first period the relationship between mandibular size resection and tumor size was 1.9, meanwhile in the second period the relation was 1.5. There was not significant difference between both periods in terms of tumor size (6.0 cm vs. 6.02 cm at the time of surgery) nor in local control and survival. Soft tissue involvement as reported by histological study was strongly associated with recurrence (p = 0.0024). Overall 5-year survival was 20%. A policy of total mandibulectomy is not associated with a better local control or survival. Extent of resection must be tailored with tumor size. Extent of margins in soft tissue is the limiting factor for local control.

Introduction Tumors of the minor salivary glands in the larynx are rare and represent

Intensity modulated radiation therapy (IMRT) allows physicians to deliver higher conformal doses to the tumour, while avoiding adjacent structures. As a result the probability of tumour control is higher and toxicity may be reduced. However, implementation of IMRT is highly complex and requires a rigorous quality assurance (QA) program both before and during treatment. The present article describes the process of implementing IMRT for localized prostate cancer in a radiation therapy department. In our experience, IMRT implementation requires careful planning due to the need to simultaneously implement specialized software, multifaceted QA programs, and training of the multidisciplinary team. Establishing standardized protocols and ensuring close collaboration between a multidisciplinary team is challenging but essential.