Global Forum of Cancer Surgeons: Cancer Surgery During the COVID-19 Pandemic: Impact and Lessons Learned.

BACKGROUND: The purpose of this article is to summarize the opinions of the surgical oncology leaders from the Global Forum of Cancer Surgeons (GFCS) about the global impact of COVID-19 pandemic on cancer surgery. METHODS: A panel session (virtual) was held at the annual Society of Surgical Oncology 2021 International Conference on Surgical Cancer Care to address the impact of COVID-19 on cancer surgery globally. Following the virtual meeting, a questionnaire was sent to all the leaders to gather additional opinions. The input obtained from all the leaders was collated and analyzed to understand how cancer surgeons from across the world adapted in real-time to the impact of COVID-19 pandemic. RESULTS: The surgical oncology leaders noted that the COVID-19 pandemic led to severe disruptions in surgical cancer care across all domains of clinical care, education, and research. Several new changes/protocols associated with increased costs were implemented to deliver safe care. Leaders also noted that preexisting disparities in care were exacerbated, and the pandemic had a detrimental effect on well-being and financial status. CONCLUSIONS: The COVID-19 pandemic has led to severe disruptions in surgical cancer care globally. Leaders of the GFCS opined that new strategies need to be implemented to prepare for any future catastrophic events based on the lessons learned from the current events. The GFCS will embark on developing such a roadmap to ensure that surgical cancer care is preserved in the future regardless of any catastrophic global events.

Upflow anaerobic filter for the degradation of adsorbable organic halides (AOX) from bleach composite wastewater of pulp and paper industry.

The removal of AOX from bleach plant effluent of pulp and paper industry was studied using upflow anaerobic filter. In this paper biodegradation of AOX at different concentrations and effect of electron donors like acetate and glucose thereon in an upflow anaerobic filter at 20 d HRT is described. Results showed significant improvement in AOX degradation when electron donors such as acetate and glucose were supplemented to the influent. AOX degradation was 88% at 28 mg AOX L(-1) and 28% at 42 mg AOX L(-1). The percent degradation efficiency was enhanced to 90.7, 90.2, and 93.0 at 28 mg AOX L(-1) when the influent was supplemented with glucose, acetate and both glucose and acetate, respectively. Similarly, the efficiency was 57, 56.6 and 79.6 at 42 mg AOX L(-1) when the influent was supplemented with glucose, acetate and both glucose and acetate, respectively. The GC-MS analysis data indicated that supplementation of the influent with electron donor increased the biodegradability of number of chlorinated organic compounds.

Anaerobic degradation of adsorbable organic halides (AOX) from pulp and paper industry wastewater.

Adsorbable organic halides (AOX) are generated in the pulp and paper industry during the bleaching process. These compounds are formed as a result of reaction between residual lignin from wood fibres and chlorine/chlorine compounds used for bleaching. Many of these compounds are recalcitrant and have long half-life periods. Some of them show a tendency to bioaccumulate while some are proven carcinogens and mutagens. Hence, it is necessary to remove or degrade these compounds from wastewater. Physical, chemical and electrochemical methods reported to remove AOX compounds are not economically viable. Different types of aerobic, anaerobic and combined biological treatment processes have been developed for treatment of pulp and paper industry wastewater. Maximum dechlorination is found to occur under anaerobic conditions. However, as these processes are designed specifically for reducing COD and BOD of wastewater, they do not ensure complete removal of AOX. This paper reviews the anaerobic biological treatments developed for pulp and paper industry wastewater and also reviews the specific micro-organisms reported to degrade AOX compounds under anaerobic conditions, their nutritional and biochemical requirements. It is imperative to consider these specific micro-organisms while designing an anaerobic treatment for efficient removal of AOX.

Application of Methanobrevibacter acididurans in anaerobic digestion.

To operate anaerobic digesters successfully under acidic conditions, hydrogen utilizing methanogens which can grow efficiently at low pH and tolerate high volatile fatty acids (VFA) are desirable. An acid tolerant hydrogenotrophic methanogen viz. Methanobrevibacter acididurans isolated from slurry of an anaerobic digester running on alcohol distillery wastewater has been described earlier by this lab. This organism could grow optimally at pH 6.0. In the experiments reported herein, M. acididurans showed better methanogenesis under acidic conditions with high VFA, particularly acetate, than Methanobacterium bryantii, a common hydrogenotrophic inhabitant of anaerobic digesters. Addition of M. acididurans culture to digesting slurry of acidogenic as well as methanogenic digesters running on distillery wastewater showed increase in methane production and decrease in accumulation of volatile fatty acids. The results proved the feasibility of application of M. acididurans in anaerobic digesters.

Methanobrevibacter acididurans sp. nov., a novel methanogen from a sour anaerobic digester.

A novel acid-tolerant, hydrogenotrophic methanogen, isolate ATMT, was obtained from an enrichment performed at pH 5.0 using slurry from an acidogenic digester running on alcohol distillery waste. The original pH of the slurry was 5.7 and the volatile fatty acid concentration was 9000 p.p.m. Cells of isolate ATMT were Gram-positive, non-motile and 0.3-0.5 microm in size. They did not form spores. The isolate could grow in the pH range 5.0-7.5, with maximum growth at pH 6.0. The optimum temperature for growth was 35 degrees C. Formate, acetate, methanol, trimethylamine, 2-propanol and 2-butanol were not utilized as growth substrates. Rumen fluid and acetate were required for growth on H2/CO2. Coenzyme M and 2-methylbutyric acid were not required in the presence of rumen fluid. 16S rDNA sequence analysis confirmed the signature sequence of the genus Methanobrevibacter. Morphological and biochemical characteristics of the isolate, together with the 16S rDNA sequence analysis, clearly revealed that the isolate could not be accommodated within any of the existing species of the genus Methanobrevibacter. Therefore, it is proposed that a novel species of the genus Methanobrevibacter should be created for this isolate, Methanobrevibacter acididurans sp. nov., and the type strain is

Comparative evaluation of function after surgery for cancer of the alveolobuccal complex.

PURPOSE: The current study was undertaken to assess the functional deficit after hemiresection of the mandible and to determine whether lateral segment resection with reconstruction was a functionally superior alternative in the management of patients suffering from alveolobuccal cancer. PATIENTS AND METHODS: Eighty-three patients were assigned to one of two main groups: Group I, hemiresection of the mandible (n = 47), and group II, lateral segment defects (n = 36). Functional assessment of patients included subjective evaluation of overall well-being, feeding, and cosmesis, as well as objective assessment of mastication, speech, and cosmesis. Mean scores for each of these categories were compared across groups using the Duncan Multiple Range Test with .01 confidence intervals. RESULTS: Subjective assessment of overall well-being, feeding, and cosmesis did not yield statistically significant differences between groups. Objective evaluation of mastication showed significantly better function after hemiresection in dentate patients as compared with their edentulous counterparts. However, masticatory scores for hemimandibulectomy patients with intact residual dentition were not significantly different from those for patients whose lateral segmental defects had been reconstructed. Although objective cosmetic scores for reconstruction of lateral segment defects were significantly better than those for hemiresection of the mandible, most patients in the latter group accepted the resultant deformity as a consequence of their treatment and did not let it affect their routine activities. CONCLUSION: Until functional results in patients undergoing lateral segmental resection for alveolobuccal cancer can be improved by better prosthetic techniques, hemiresection of the mandible remains a simple, safe, reliable, and cost-effective option that produces acceptable postoperative function.

Reconstruction with different free flaps in oro-facial cancer patients.

In 75 patients following ablative surgery of head and neck cancer, reconstruction was attempted with free tissue transfer techniques under magnification. It was possible to do free tissue transfers in 69 cases. In 6 cases it was not possible to harvest free flaps successfully and alternative reconstructive procedure was carried out due to unavoidable circumstances and various reasons: 1. unsuitable venous drainage, as in Anterior Rib Osteomyocutaneous Composite Flap, AROCF (2 cases), 2. injury to vessels during flap harvest, as in parascapular flap (1 case), 3. residual disease unable to excise (2 cases) and 4. unsuitable proposition (1 case), due to emergency curfew imposed suddenly. These 6 cases were not included in the study. Free tissue transfer was successful in 64 cases (92.7%) and there was a total failure in 5 cases where delayed secondary salvage surgery was performed. Out of 69 cases, in 65 cases reconstructions were carried out immediately, primarily as one-stage operative procedure. Their functional, cosmetic results and complications during the operative and post-operative period are analyzed and discussed. Inter-maxillary fixation was never used to maintain the bite alignment. All cases were given a bite guide prosthesis in the early post-operative period, to improve the bite alignment when it was necessary.

Folded free radial forearm flap for reconstruction of full-thickness defects of the cheek.

BACKGROUND: Full thickness defects of the cheek have been conventionally reconstructed using the folded forehead flap, cervical flap, pectoralis major myocutaneous flap, or deltopectoral flap in various combinations. We report a modified technique of folding the radial forearm flap for reconstruction of full-thickness defects of the cheek. METHODS: The free radial forearm flap is a type C fasciocutaneous flap based on the radial artery along with its vena commitans and superficial forearm vein. The size and shape of the flap are determined according to the dimensions of the surgical defect. The flap is then lifted off with the fascia of the forearm making it a fasciocutaneous flap, in which the radial artery lies deep to the fascia and gives numerous branches. The flap is disconnected from the donor site only after the recipient vessels have been prepared for anastomosis. Vascular anastomosis is then performed using the operating microscope. This technique was used in 13 patients with carcinoma of the buccal mucosa who underwent fill-thickness excision of the cheek. RESULTS: Flap edema was observed in 4 patients in the immediate post-operative period. Necrosis of the outer paddle was seen in 1 patient. Donor site morbidity was seen in 4 patients who required dressings on an outpatient basis for up to 3 weeks. CONCLUSION: Single-stage reconstruction of full-thickness defects of the cheek with the folded free radial forearm flap is reliable and produces excellent cosmesis with minimal donor site morbidity.

Reconstruction of the mandible with vascularized iliac crest flap--initial experience at the Tata Memorial Hospital.

Resection of the mandible for cancer of the oral cavity can result in gross functional and aesthetic deformity. Inspite of technological advances, reconstruction of mandibular defects remains one of the most challenging procedures in head and neck surgery. Conventional methods like alloplastic implants and bone grafting have a high rate of failure. The advent of microvascular techniques for mandibular reconstruction has revolutionised the management of these patients. We present our initial experience based on 18 patients who underwent vascularised iliac creast transfer at the Tata Memorial Hospital between November, 1992 and January, 1994. The operative technique of raising, shaping and fixation of the iliac crest flap as well as advantages and disadvantages are discussed. Postoperative graft viability was assessed using 99mTc-MDP scans during the 1st, 3rd and 12th weeks after surgery. We lost 3 flaps (16.4%) due to uncontrolled infection and vessel thrombosis. All of the remaining patients demonstrated good uptake on bone scans and satisfactory bony union on OPG. We conclude that mandibular reconstruction using the vascularised iliac crest is reliable and produces acceptable postoperative functional results with 88% of patients having no swallowing difficulty, 83% with normal speech and excellent cosmesis in 83% (15/18) of the patients.

Reconstruction of chest wall defects following extirpative surgery.

Reconstructive procedures following chest wall resection pose a special surgical challenge. With modern surgical technique, a wide range of reconstructive options are at the surgeon's disposal and, hence it is imperative that the appropriate procedure be selected in a given patient. A total of 64 patients underwent resection of malignant chest wall tumors at the Tata Memorial Hospital. The technique of preference at our institution for reconstruction of full-thickness chest wall defects uses a combination of autogenous fascia lata and Marlex mesh. We present our experience with chest wall reconstruction following extirpative surgery in these patients.

Osteomyocutaneous flap reconstruction for major mandibular defects.

Mandibular defects after composite resections for carcinoma of the buccal mucosa require immediate restitution of both form and function with an acceptable cosmetic result. The pectoralis major osteomyocutaneous flap (PM-OMC) provides restoration of bone, soft tissue and skin with minimum morbidity. The procedure is technically simple, and in our series reconstruction using this flap has been performed by consultants, fellows and residents in training. We present a series of 116 PM-OMC flaps with good postoperative mastication in more than 70% of cases, and satisfactory swallowing and intelligible speech in 85% patients.