Evolving Concepts toward Individualized Treatment of Squamous Cell Carcinoma of the Anus

Treatment of squamous cell carcinoma of the anus has evolved over the last 5 decades from radical surgery to combined chemoradiation therapy. Radiation treatment techniques have dramatically improved with the development of more powerful computers, algorithms and treatment machines. The clinical impact of the modern radiation treatment techniques, such as intensity-modulated radiotherapy and volumetric modulated arc therapy, is discussed. The standard-of-care regimen still is concurrent Mitomycin C, 5-fluorouracil and high-dose radiation, as was conceived 45 years ago. Variants of this schedule are discussed in this chapter. International guidelines have been generated and implemented. Whereas concurrent chemoradiation therapy is the treatment of choice for locally advanced tumors, early tumors are probably adequately controlled with either reduced dose chemoradiation therapy or radiation therapy alone. Prognostic factors, such as high-risk human papillomavirus, epidermal growth factor receptor and immune response, will be highlighted. The role of surgery in primary care is limited to local excision of T1N0 tumors ≤ 1 cm of the anal margin. Salvage radical surgery is limited to locoregional recurrent, non-metastasized and resectable tumors after chemoradiation therapy. In addition, new treatment modalities, such as targeted therapy and immunotherapy, will be discussed. Current research aims at refining prognostic subgroups to further individualize treatment strategy, implementing quality assurance protocols in international trials and investigating the molecular profile of squamous cell carcinoma of the anus, in order to identify new treatment avenues. This will hopefully change the landscape of anal cancer treatment in the future

Current practices concerning the assessment and treatment of lateral lymph nodes in low rectal cancer:a survey among colorectal surgeons in The Netherlands

Purpose: The presence of lateral lymph nodes (LLNs) in patients with rectal cancer is not always acknowledged by the multidisciplinary team or treated in a standardized manner, and (inter)national guidelines concerning this topic are lacking. This study aimed to evaluate current practices regarding the assessment and treatment of LLNs in rectal cancer patients based on a survey among Dutch colorectal surgeons. Methods: An online survey was sent to members of the Dutch Association of Coloproctology. The survey consisted of 16 questions addressing their views on diagnosis, restaging, and treatment approaches for suspicious LLNs. Results: A total of 62 surgeons from 50 Dutch hospitals responded. For patients with a distal cT3/T4 rectal tumor; lateral lymph node compartments were routinely discussed during multidisciplinary meetings in only nine hospitals (18%). When defining what makes an LLN suspicious; the size threshold varied from &gt;3 to &gt;10 mm (median 7, SD 2), and MRI-based malignant features were mentioned by 29 surgeons (47%). Surgeons stated eight different treatment strategies as their designated treatment of suspicious LLNs. A total of 33 surgeons (53%) would add a radiotherapy boost to the neoadjuvant treatment. In cases of surgical resection; 12 surgeons (19%) would remove the suspicious LLN by ‘node-picking’ and 44 surgeons (71%) would perform a lateral lymph node dissection. The variation was not influenced by hospital type or surgeon's experience. Conclusion: These results highlight the vast variation in the awareness, definition of suspicious LLNs in rectal cancer, and different treatment approaches. International guidelines based on further research are warranted.</p

Current practices concerning the assessment and treatment of lateral lymph nodes in low rectal cancer:a survey among colorectal surgeons in The Netherlands

Purpose: The presence of lateral lymph nodes (LLNs) in patients with rectal cancer is not always acknowledged by the multidisciplinary team or treated in a standardized manner, and (inter)national guidelines concerning this topic are lacking. This study aimed to evaluate current practices regarding the assessment and treatment of LLNs in rectal cancer patients based on a survey among Dutch colorectal surgeons. Methods: An online survey was sent to members of the Dutch Association of Coloproctology. The survey consisted of 16 questions addressing their views on diagnosis, restaging, and treatment approaches for suspicious LLNs. Results: A total of 62 surgeons from 50 Dutch hospitals responded. For patients with a distal cT3/T4 rectal tumor; lateral lymph node compartments were routinely discussed during multidisciplinary meetings in only nine hospitals (18%). When defining what makes an LLN suspicious; the size threshold varied from &gt;3 to &gt;10 mm (median 7, SD 2), and MRI-based malignant features were mentioned by 29 surgeons (47%). Surgeons stated eight different treatment strategies as their designated treatment of suspicious LLNs. A total of 33 surgeons (53%) would add a radiotherapy boost to the neoadjuvant treatment. In cases of surgical resection; 12 surgeons (19%) would remove the suspicious LLN by ‘node-picking’ and 44 surgeons (71%) would perform a lateral lymph node dissection. The variation was not influenced by hospital type or surgeon's experience. Conclusion: These results highlight the vast variation in the awareness, definition of suspicious LLNs in rectal cancer, and different treatment approaches. International guidelines based on further research are warranted.</p

Selected stage IV rectal cancer patients managed by the watch-and-wait approach after pelvic radiotherapy:a good alternative to total mesorectal excision surgery?

Aim: The aim of this study was to assess the clinical and oncological outcome of a selected group of stage IV rectal cancer patients managed by the watch-and-wait approach following a (near-)complete response of the primary rectal tumour after radiotherapy. Method: Patients registered in the Dutch watch-and-wait registry since 2004 were selected when diagnosed with synchronous stage IV rectal cancer. Data on patient characteristics, treatment details, follow-up and survival were collected. The 2-year local regrowth rate, organ-preservation rate, colostomy-free rate, metastatic progression-free rate and 2- and 5-year overall survival were analysed. Results: After a median follow-up period of 35 months, local regrowth was observed in 17 patients (40.5%). Nine patients underwent subsequent total mesorectal excision, resulting in a permanent colostomy in four patients. The 2-year local regrowth rate was 39.9%, the 2-year organ-preservation rate was 77.1%, the 2-year colostomy-free rate was 88.1%, and the 2-year metastatic progression-free rate was 46.7%. The 2- and 5-year overall survival rates were 92.0% and 67.5%. Conclusion: The watch-and-wait approach can be considered as an alternative to total mesorectal excision in a selected group of stage IV rectal cancer patients with a (near-)complete response following pelvic radiotherapy. Despite a relatively high regrowth rate, total mesorectal excision and a permanent colostomy can be avoided in the majority of these patients.</p

Selected stage IV rectal cancer patients managed by the watch-and-wait approach after pelvic radiotherapy:a good alternative to total mesorectal excision surgery?

Aim: The aim of this study was to assess the clinical and oncological outcome of a selected group of stage IV rectal cancer patients managed by the watch-and-wait approach following a (near-)complete response of the primary rectal tumour after radiotherapy. Method: Patients registered in the Dutch watch-and-wait registry since 2004 were selected when diagnosed with synchronous stage IV rectal cancer. Data on patient characteristics, treatment details, follow-up and survival were collected. The 2-year local regrowth rate, organ-preservation rate, colostomy-free rate, metastatic progression-free rate and 2- and 5-year overall survival were analysed. Results: After a median follow-up period of 35 months, local regrowth was observed in 17 patients (40.5%). Nine patients underwent subsequent total mesorectal excision, resulting in a permanent colostomy in four patients. The 2-year local regrowth rate was 39.9%, the 2-year organ-preservation rate was 77.1%, the 2-year colostomy-free rate was 88.1%, and the 2-year metastatic progression-free rate was 46.7%. The 2- and 5-year overall survival rates were 92.0% and 67.5%. Conclusion: The watch-and-wait approach can be considered as an alternative to total mesorectal excision in a selected group of stage IV rectal cancer patients with a (near-)complete response following pelvic radiotherapy. Despite a relatively high regrowth rate, total mesorectal excision and a permanent colostomy can be avoided in the majority of these patients.</p

An Evaluation and Implementation of Rule-Based Home Energy Management System Using the Rete Algorithm

In recent years, sensors become popular and Home Energy Management System (HEMS) takes an important role in saving energy without decrease in QoL (Quality of Life). Currently, many rule-based HEMSs have been proposed and almost all of them assume “IF-THEN” rules. The Rete algorithm is a typical pattern matching algorithm for IF-THEN rules. Currently, we have proposed a rule-based Home Energy Management System (HEMS) using the Rete algorithm. In the proposed system, rules for managing energy are processed by smart taps in network, and the loads for processing rules and collecting data are distributed to smart taps. In addition, the number of processes and collecting data are reduced by processing rules based on the Rete algorithm. In this paper, we evaluated the proposed system by simulation. In the simulation environment, rules are processed by a smart tap that relates to the action part of each rule. In addition, we implemented the proposed system as HEMS using smart taps

Tumour ADC measurements in rectal cancer: effect of ROI methods on ADC values and interobserver variability

OBJECTIVES: To assess the influence of region of interest (ROI) size and positioning on tumour ADC measurements and interobserver variability in patients with locally advanced rectal cancer (LARC). METHODS: Forty-six LARC patients were retrospectively included. Patients underwent MRI including DWI (b0,500,1000) before and 6-8 weeks after chemoradiation (CRT). Two readers measured mean tumour ADCs (pre- and post-CRT) according to three ROI protocols: whole-volume, single-slice or small solid samples. The three protocols were compared for differences in ADC, SD and interobserver variability (measured as the intraclass correlation coefficient; ICC). RESULTS: ICC for the whole-volume ROIs was excellent (0.91) pre-CRT versus good (0.66) post-CRT. ICCs were 0.53 and 0.42 for the single-slice ROIs versus 0.60 and 0.65 for the sample ROIs. Pre-CRT ADCs for the sample ROIs were significantly lower than for the whole-volume or single-slice ROIs. Post-CRT there were no significant differences between the whole-volume ROIs and the single-slice or sample ROIs, respectively. The SDs for the whole-volume and single-slice ROIs were significantly larger than for the sample ROIs. CONCLUSIONS: ROI size and positioning have a considerable influence on tumour ADC values and interobserver variability. Interobserver variability is worse after CRT. ADCs obtained from the whole tumour volume provide the most reproducible results. Key Points • ROI size and positioning influence tumour ADC measurements in rectal cancer • ROI size and positioning influence interobserver variability of tumour ADC measurements • ADC measurements of the whole tumour volume provide the most reproducible results • Tumour ADC measurements are more reproducible before, rather than after, chemoradiation treatment • Variations caused by ROI size and positioning should be taken into account when using ADC as a biomarker for tumour response