Latin American Consensus on the Treatment of Head and Neck Cancer.

Head and neck squamous cell carcinoma (HNSCC) is well known as a serious health problem worldwide, especially in low-income countries or those with limited resources, such as most countries in Latin America. International guidelines cannot always be applied to a population from a large region with specific conditions. This study established a Latin American guideline for care of patients with head and neck cancer and presented evidence of HNSCC management considering availability and oncologic benefit. A panel composed of 41 head and neck cancer experts systematically worked according to a modified Delphi process on (1) document compilation of evidence-based answers to different questions contextualized by resource availability and oncologic benefit regarding Latin America (region of limited resources and/or without access to all necessary health care system infrastructure), (2) revision of the answers and the classification of levels of evidence and degrees of recommendations of all recommendations, (3) validation of the consensus through two rounds of online surveys, and (4) manuscript composition. The consensus consists of 12 sections: Head and neck cancer staging, Histopathologic evaluation of head and neck cancer, Head and neck surgery-oral cavity, Clinical oncology-oral cavity, Head and neck surgery-oropharynx, Clinical oncology-oropharynx, Head and neck surgery-larynx, Head and neck surgery-larynx/hypopharynx, Clinical oncology-larynx/hypopharynx, Clinical oncology-recurrent and metastatic head and neck cancer, Head and neck surgery-reconstruction and rehabilitation, and Radiation therapy. The present consensus established 48 recommendations on HNSCC patient care considering the availability of resources and focusing on oncologic benefit. These recommendations could also be used to formulate strategies in other regions like Latin America countries.

Analysis of the Pediatric Radiotherapy Landscape in Mexico and a Subsequent Educational e-Contouring Intervention.

PURPOSE: Mexico and Central America have the highest childhood cancer incidence in the West. Pediatric-specific oncology knowledge contributes to the disparity. We sought to (1) determine the self-identified treatment patterns and needs of Mexican pediatric radiation oncologists and (2) pilot a workshop to improve contouring accuracy. MATERIALS AND METHODS: Partnering with local experts and the Sociedad Mexicana de Radioterapeutas (SOMERA), a 35-question survey was designed to ascertain pediatric radiotherapy capacity and distributed through the SOMERA listserv. The most challenging malignancies were selected for workshop. Participants received precontouring and postcontouring homework to assess improvement per the Dice metric. The Wilcoxon sign-rank test was used for comparative statistics. RESULTS: Ninety-four radiation oncologists attempted and 79 completed the survey. Forty-four (76%) felt comfortable treating a pediatric patient, and 36 (62%) were familiar with national protocols for pediatric treatment. Most had access to nutrition, rehabilitation, endocrinology, and anesthesia; 14% had access to fertility services and 27% to neurocognitive support; 11% noted no support, and only one respondent had child-life support. The postsurvey contouring workshop was conducted for high-grade glioma, medulloblastoma, and Hodgkin lymphoma. Significant improvements were seen in all target volumes. CONCLUSION: We present the first national survey of Mexico's pediatric radiotherapy capacity and Latin American e-contouring educational intervention with preworkshop and postworkshop Dice metrics, noting statistically significant improvement in all target volumes. Participation improved compared with prior experience through SOMERA partnership and Continuing Medical Education incentivization.

Cross-Sectional International Survey to Determine the Educational Interests of Spanish-Speaking Latin American Radiation Oncologists.

PURPOSE: With the existing oncology disparities in Latin America, physician expertise has been cited as a possible contributor to inferior oncologic outcomes in some cancers. As two-dimensional radiotherapy rapidly evolved to intensity-modulated radiation therapy in Latin America, adequate contouring education is an actionable target to improving physician knowledge and clinical outcomes. Yet, topics of interest to Latin American radiation oncologists are underreported. We assessed Latin American interest in a virtual platform for case discussion and identified the educational topics of most interest to them. MATERIALS AND METHODS: A Spanish-language online survey was designed by a team of Latin American educators. The questions assessed professional nationality, desire for an online educational platform for case presentation, career length, and topics of interest. Educational topics included head and neck (H&N), CNS, GI, lung, gynecologic, breast, and pediatric cancers, lymphoma, sarcoma, stereotactic body radiotherapy (SBRT), brachytherapy, and medical physics. RESULTS: One hundred thirty-three surveys were included for analysis. Overall, 127 respondents (98%) affirmed interest in participating in a virtual platform for case discussion and treatment advances. The most popular educational themes were H&N cancers (24%), SBRT (14%), and CNS cancers (13%). Of countries with > 10 respondents, the most popular educational topic remained H&N cancers for Argentina, Chile, and Mexico, but the most popular topic among Peruvian respondents was CNS cancer (27%). CONCLUSION: With international collaboration and a large sample size, we present the first survey results describing Latin American radiation oncology educational interests. Participants were overwhelmingly interested in a virtual platform, and most were specifically interested in H&N cancer education. These results can be used for focused didactic preparation in Latin America. Future efforts should expand on improving representation and outreach among Central American radiation oncologists.

Delineation of the primary tumour Clinical Target Volumes (CTV-P) in laryngeal, hypopharyngeal, oropharyngeal and oral cavity squamous cell carcinoma: AIRO, CACA, DAHANCA, EORTC, GEORCC, GORTEC, HKNPCSG, HNCIG, IAG-KHT, LPRHHT, NCIC CTG, NCRI, NRG Oncology, PHNS, SBRT, SOMERA, SRO, SSHNO, TROG consensus guidelines.

PURPOSE: Few studies have reported large inter-observer variations in target volume selection and delineation in patients treated with radiotherapy for head and neck squamous cell carcinoma. Consensus guidelines have been published for the neck nodes (see Grégoire et al., 2003, 2014), but such recommendations are lacking for primary tumour delineation. For the latter, two main schools of thoughts are prevailing, one based on geometric expansion of the Gross Tumour Volume (GTV) as promoted by DAHANCA, and the other one based on anatomical expansion of the GTV using compartmentalization of head and neck anatomy. METHOD: For each anatomic location within the larynx, hypopharynx, oropharynx and oral cavity, and for each T-stage, the DAHANCA proposal has been comprehensively reviewed and edited to include anatomic knowledge into the geometric Clinical Target Volume (CTV) delineation concept. A first proposal was put forward by the leading authors of this publication (VG and CG) and discussed with opinion leaders in head and neck radiation oncology from Europe, Asia, Australia/New Zealand, North America and South America to reach a worldwide consensus. RESULTS: This consensus proposes two CTVs for the primary tumour, the so called CTV-P1 and CVT-P2, corresponding to a high and lower tumour burden, and which should be associated with a high and a lower dose prescription, respectively. CONCLUSION: Implementation of these guidelines in the daily practice of radiation oncology should contribute to reduce treatment variations from clinicians to clinicians, facilitate the conduct of multi-institutional clinical trials, and contribute to improved care of patients with head and neck carcinoma.

IAEA randomised trial of optimal single dose radiotherapy in the treatment of painful bone metastases.

BACKGROUND: To determine the optimal single-dose radiotherapy schedule for pain from bone metastases in a multi-centre, international, randomised trial. PATIENTS AND METHODS: 651 patients were randomised to either 8Gy (n=325) or 4Gy (n=326) radiotherapy. Pain at 4, 8, 12, 24 and 52weeks was assessed using a Categorical Scale (CS) and a Visual Analogue Scale (VAS). The primary endpoint was response at 4weeks. RESULTS: There was no significant difference in patient demographics and other co-variates. The complete response (CR) rate and ORR (complete or partial response) for all follow-up times were higher after 8Gy (p=0.02). The Kaplan-Meier actuarial rate (categorical scale) at 4weeks for ORR was 80% after 8Gy compared to 68% after 4Gy (p=0.0015). 117 re-treatments were given of which 72 were in the 4Gy group and 45 in 8Gy arm (p=0.01). CONCLUSIONS: There was a marked consistent difference in pain relief at all time points in favour of 8Gy. These data reinforce the case for single dose 8Gy radiotherapy to be recommended for metastatic bone pain in all healthcare settings.

Cancer-initiating cells derived from established cervical cell lines exhibit stem-cell markers and increased radioresistance.

BACKGROUND: Cancer-initiating cells (CICs) are proposed to be responsible for the generation of metastasis and resistance to therapy. Accumulating evidences indicates CICs are found among different human cancers and cell lines derived from them. Few studies address the characteristics of CICs in cervical cancer. We identify biological features of CICs from four of the best-know human cell lines from uterine cervix tumors. (HeLa, SiHa, Ca Ski, C-4 I). METHODS: Cells were cultured as spheres under stem-cell conditions. Flow cytometry was used to detect expression of CD34, CD49f and CD133 antigens and Hoechst 33342 staining to identify side population (SP). Magnetic and fluorescence-activated cell sorting was applied to enrich and purify populations used to evaluate tumorigenicity in nude mice. cDNA microarray analysis and in vitro radioresistance assay were carried out under standard conditions. RESULTS: CICs, enriched as spheroids, were capable to generate reproducible tumor phenotypes in nu-nu mice and serial propagation. Injection of 1 × 10³ dissociated spheroid cells induced tumors in the majority of animals, whereas injection of 1 × 105 monolayer cells remained nontumorigenic. Sphere-derived CICs expressed CD49f surface marker. Gene profiling analysis of HeLa and SiHa spheroid cells showed up-regulation of CICs markers characteristic of the female reproductive system. Importantly, epithelial to mesenchymal (EMT) transition-associated markers were found highly expressed in spheroid cells. More importantly, gene expression analysis indicated that genes required for radioresistance were also up-regulated, including components of the double-strand break (DSB) DNA repair machinery and the metabolism of reactive oxygen species (ROS). Dose-dependent radiation assay indicated indeed that CICs-enriched populations exhibit an increased resistance to ionizing radiation (IR). CONCLUSIONS: We characterized a self-renewing subpopulation of CICs found among four well known human cancer-derived cell lines (HeLa, SiHa, Ca Ski and C-4 I) and found that they express characteristic markers of stem cell, EMT and radioresistance. The fact that CICs demonstrated a higher degree of resistance to radiation than differentiated cells suggests that specific detection and targeting of CICs could be highly valuable for the therapy of tumors from the uterine cervix.

Overview of brachytherapy resources in Latin America: a patterns-of-care survey.

PURPOSE: Relatively little is known about available resources and patterns of practice for brachytherapy (BT) in Latin America. To rectify this situation, we performed a patterns-of-care survey whose aim was to assess the human and material resources available for BT in Latin America and document current clinical practices. METHODS AND MATERIALS: A total of 392 radiotherapy (RT) centers located in 17 Latin American countries were asked to complete an online survey that included detailed questions about BT practices, facilities, and staffing. The study was coordinated through central offices located in Spain and Peru. National coordinators were appointed to manage the survey in each individual country. RESULTS: Overall, 77 of the 392 institutions (20%) completed the questionnaire. Of the 14 countries with at least one response, the participation rate was 35% (77 of 223 RT centers). The average number of patients (RT+BT) per center was 917. The mean number of BT patients per center increased by 46% (from 105 to 153 patients) from 2002 to 2007. Gynecologic localizations (endometrium, cervix, and vagina) accounted for 95% of treatments, and the uterine cervix was the most common tumor site (75% of all treatments). CONCLUSIONS: In Latin America, BT is most commonly used to treat gynecologic tumors, particularly of the cervix. Relatively few interventions were performed for breast and prostate. This was the first study of its kind in this region and should be repeated periodically.

Prognostic significance of pathological response after neoadjuvant chemotherapy or chemoradiation for locally advanced cervical carcinoma.

BACKGROUND: Cisplatin-based chemoradiation is the standard of care for locally advanced cervical cancer patients; however, neoadjuvant modalities are currently being tested. Neoadjuvant studies in several tumor types have underscored the prognostic significance of pathological response for survival; however there is a paucity of studies in cervical cancer investigating this issue. METHODS: Four cohorts of patients with locally advanced cervical carcinoma (stages IB2-IIIB); included prospectively in phase II protocols of either neoadjuvant chemotherapy with 1) cisplatin-gemcitabine, 2) oxaliplatin-gemcitabine, 3) carboplatin-paclitaxel or 4) chemoradiation with cisplatin or cisplatin-gemcitabine followed by radical hysterectomy were analyzed for pathological response and survival. RESULTS: One-hundred and fifty three (86%) of the 178 patients treated within these trials, underwent radical hysterectomy and were analyzed. Overall, the mean age was 44.7 and almost two-thirds were FIGO stage IIB. Pathological response rates were as follows: Complete (pCR) in 60 cases (39.2%), Near-complete (p-Near-CR) in 24 (15.6 %) and partial (pPR) in 69 cases (45.1%). A higher proportion rate of pCR was observed in patients treated with chemoradiotherapy (with cisplatin [19/40, 47.5%]; or with cisplatin-gemcitabine [24/41, 58.5%] compared with patients receiving only chemotherapy, 6/23 (26%), 3/8 (37.5%) and 8/41 (19.5%) for cisplatin-gemcitabine, oxaliplatin-gemcitabine and carboplatin-paclitaxel respectively [p = 0.0001]). A total of 29 relapses (18.9%) were documented. The pathological response was the only factor influencing on relapse, since only 4/60 (6.6%) patients with pCR relapsed, compared with 25/93 (26.8%) patients with viable tumor, either pNear-CR or pPR (p = 0.001). Overall survival was 98.3% in patients with pCR versus 83% for patients with either pNear-CR or pPR (p = 0.009). CONCLUSION: Complete pathological response but no Near-complete and partial responses is associated with longer survival in cervical cancer patients treated with neoadjuvant chemotherapy or chemoradiotherapy.

Routine management of locally advanced cervical cancer with concurrent radiation and cisplatin. Five-year results.

BACKGROUND: Globally, cervical cancer primarily affects socially disadvantaged women. Five randomized trials were the foundation for adopting cisplatin-based chemotherapy during radiation as the standard of care for high-risk patients after primary radical hysterectomy who require adjuvant radiation and for locally advanced patients treated with definitive radiation. These results were obtained in clinical trials performed in carefully prepared academic centers; hence, we sought to determine whether these results could be reproduced when patients were treated on an out-of-protocol basis. METHODS: We reviewed the files of 294 patients with locally advanced cervical cancer who received radiation plus weekly cisplatin as routine management between 1999 to 2003, and analyzed treatment compliance, response rate, toxicity, and survival. RESULTS: A total of 294 patients who received radiation and cisplatin were analyzed. Mean age was 43.8 years (range, 26-68 years). The majority of cases were squamous cell carcinoma (87.8%), and distribution according to International Federation of Gynecology and Obstetrics (FIGO) stage was as follows: IB2-IIA, 23%; IIB, 53.3%, and IIIB, 23%; there were only two IVA cases. Overall, 96% of patients completed external beam, and intracavitary therapy. The majority of patients (67%) received the planned six courses of weekly cisplatin. Complete responses were achieved in 243 (83%) patients, whereas 51 (17%) had either persistent (32 patients, 10.8%) or progressive (19 patients, 6.4%) disease. At median follow-up (28 months; range, 2-68 months), 36 patients (12.2%) have relapsed (locally 30.5, and systemically, 69.5%). The most common toxicities were hematologic and gastrointestinal, in the majority of cases considered mild-moderate. At median follow-up (28 months; range, 2-68 months), overall and progression-free survival are 76.5 and 67%, respectively. CONCLUSION: Our results support use of chemoradiation with six weekly applications of cisplatin at 40 mg/m2 during external radiation for routine management of locally advanced cervical cancer.

Overview of radiotherapy resources in Latin America: a survey by the International Atomic Energy Agency (IAEA).

BACKGROUND AND PURPOSE: An analysis of the resources for radiotherapy in Latin America was done to establish a baseline to help plan future development in the region. PATIENTS AND METHODS: The data from 19 countries were obtained during three International Atomic Energy Agency (IAEA) regional meetings. The survey covered radiotherapy centres, major equipment and personnel. The centres were categorised into four different levels. Data were related to economic and population indices. RESULTS: Four hundred and seventy centres were identified in 18 countries. Centres were divided into 4 levels: half were included in level 1, 25% in level 2 and 18% in level 0 (stand alone teletherapy machines). Human resource represents 933 radiation oncologists, 357 physicists and 2326 radiation therapy technologists. In general, availability of equipment and personnel was related to economic status of the country. CONCLUSIONS: Although there is a shortfall of equipment, the major restriction to patient service is an insufficient number of specialists in 16 of the 18 countries. An upgrade of standards in many centres is required to offer a comprehensive radiation oncology service. The information provided in this paper represents a useful base to plan future development in terms of equipment installation and training programs.

Hybrid tumours of the salivary glands. A report of two cases involving the palate and a review of the literature.

Hybrid tumours are very rare salivary gland lesions composed of two or more different tumoural entities in a single neoplasm that arise within a definite topographical region. In most cases adenoid cystic carcinoma has been the predominant component in these lesions. In this study we describe two patients with hybrid tumours located in the palate, one in a 49-year-old woman and one in a 71-year-old man. The first case involved adenoid cystic carcinoma and mucoepidermoid carcinoma, and the patient in the second case exhibited adenoid cystic carcinoma and epithelial-myoepithelial carcinoma. Both patients were treated with surgery and radiotherapy, and there has been no evidence of recurrence after 13 and 36 months of follow-up, respectively. The recognition of the histologic component with the higher grade of malignancy in every case of hybrid tumour of the salivary glands is a necessary step to determine the biological behaviour and, consequently, to determine the proper therapeutic approach.

Long-term immune dysfunction after radiotherapy to the head and neck area.

BACKGROUND: Hematological side effects are not generally expected due to radiotherapy involving limited radiation fields; however, patients with squamous cell carcinoma of the head and neck (SCCH and N) receiving radiation therapy frequently have chronic intraoral infections. Xerostomia has been implicated as a cause of it, but local or systemic immune alterations are not usually considered. METHODS: With the purpose of evaluating the impact of radiotherapy treatment to different anatomic sites on immune function, 70 patients were evaluated during and after radiotherapy: 50 cases with SCCH and N, 10 with squamous cell carcinoma of the uterine cervix (SCCUC) and 10 patients with central nervous system tumors (CNS). We analyzed lymphocyte counts and T-cell subsets, and over time, their association with the presence of intracellular infections and disease-free survival. RESULTS: Severe lymphopenia was observed in patients with SCCUC and SCCH and N by the fifth week of treatment. Patients with CNS tumors developed mild lymphopenia. In patients with SCCH and N and UC, lower counts were seen in B cells and total T lymphocyte counts including both CD4(+) and CD8(+) cell subsets. The patients with SCCUC recovered lymphocyte counts by the 24th month but T-cell subsets lagged behind. None of the SCCH and N patients had fully recovered by 60 months of follow-up. Recurrence correlates with low lymphocyte counts. DISCUSSION: This work highlights the vulnerability of the head and neck area to the impact of radiotherapy as a reservoir of lymphoid cells. The possibility of recovery as a consequence of thymopoiesis and/or peripheral clonal expansion may limit the antigen-specific recognition of relevant tumor or microbial antigens and cause significant and prolonged immune alterations that may impact long-term survival.