A 62-year-old female presented with severe COVID-19 pneumonitis requiring admission in the Intensive Care Unit. Her medical history includes a previous renal transplant for which she usually takes mycophenolate, tacrolimus and prednisone. Since admission, the patient had been having intermittent and vague abdominal pain. However, on the seventh day of admission, she developed a sudden escalation in abdominal pain. There was no history of trauma. Serial examinations demonstrated abdominal tenderness with nil peritonism, however, she developed hypotension and tachycardia. Computed tomography (CT) of the abdomen and pelvis with intravenous contrast demonstrated a large right-sided retroperitoneal phlegmon with gas tracking cranially, as seen in Fig. 1. She had a white cell count of 12.1 mmol/L, C-reactive protein of 3 mg/L and a haemoglobin count of 90 g/L. The latter was a significant drop from her baseline of 130 g/L. Coagulation studies were normal. She was on low-dose enoxaparin for venous thromboembolism prophylaxis. Decision was made to proceed to laparotomy due to concerns of perforated diverticulitis with developing necrotising fasciitis. Intraoperative findings revealed a large retroperitoneal haematoma extending inferiorly from below the root of the small bowel mesentery, extending to the pelvis. No evidence of intraabdominal sepsis or diverticulitis was found. The CT scan and exploratory laparotomy failed to demonstrate the actual cause of pneumoretroperitoneum. As there was no prior history of instrumentation, the air associated with the haematoma was presumed to be from bacterial superinfection. There was no evidence of active bleeding. The patient was then treated with broad-spectrum antibiotics. Unfortunately, she developed a midline fascial dehiscence necessitating a return to theatre for closure. She recovered well from all these and was then discharged to a rehabilitation service for ongoing physical conditioning. Spontaneous retroperitoneal haematoma (SRH) is a relatively uncommon phenomenon, typically occurring secondary to trauma, although a proportion of cases are idiopathic.1 Risk factors for the development of SRH include anticoagulation or antiplatelet therapy, inflammatory disorders, vasculitic disorders, recent instrumentation and old age.2 While clinical presentation of SRH is non-specific in most cases, deterioration can be rapid unless promptly recognized and treated appropriately. Diagnosis is typically made based on CT scan.3 Considering that ruptured retroperitoneum may cause uncontrollable haemorrhage and increase mortality, treatment modalities typically include resuscitation by restoration of circulating volume and urgent interventional radiology coiling/embolization.4 In unstable patients, operative management remains a viable treatment option. Pneumoretroperitoneum is usually associated with trauma, colonic or duodenal perforation and instrumentation, either endoscopically or laparoscopically.5 Other causes include superinfected necrotizing pancreatitis, necrotizing fasciitis, and abscess formation.3 In this case, the pneumoretroperitoneum was attributed to a superinfection of the haematoma which was likely induced by the patient's concomitant immunosuppressed state and severe COVID-19 infection. To the best of our knowledge, we have not encountered many cases of superimposed infection of a SRH, particularly without instrumentation. Retroperitoneal haematoma is largely managed with angioembolization. However, the presence of gas within a SRH may confuse the diagnostic process and as such, may necessitate operative intervention, particularly to exclude a more sinister pathology. Marie Shella De Robles: Supervision; writing – original draft; writing – review and editing. Robert Winn: Supervision. Raphael Gonzales: Conceptualization; writing – original draft; writing – review and editing.

The elderly population comprises a significant proportion of patients diagnosed with rectal cancer. However, there is a lack of evidence to guide treatment decisions in this group. Thus, this multicentre study compares the histopathology, treatment patterns and outcomes between the elderly and young populations with non-metastatic rectal cancer. The present study reported on the clinicopathological variables, treatment modalities and survival outcomes in 736 patients diagnosed with non-metastatic rectal cancer between 2006 and 2015. Patients were divided into the following two groups, <70 and ≥70 years of age, which were compared using Chi-square and survival outcome analysis using Kaplan-Meier. Elderly patients made up nearly half of the cohort and were less likely to undergo trimodality therapy or be discussed in a multidisciplinary meeting. Surgery in the elderly patients was associated with increased mortality. Elderly patients had worse cancer-specific survival (75 vs. 85%), which was particularly evident in stage III disease (hazard ratio, 2.1). Elderly patients in this subgroup treated with trimodality therapy had similar survival outcomes to younger patients. Elderly patients with locally advanced rectal cancer comprise a large proportion of the patient cohort. Consideration should be given for trimodality therapy in this group, taking into account biological age, especially in the context of increasing life expectancy and improvement in the management of age-related comorbidities.

BACKGROUND:Colorectal cancer (CRC) is one of the most commonly diagnosed malignancies globally; however, a survival paradox has been observed unique to this malignancy. The aim of this study was to review survival outcomes of patients diagnosed with stage II and stage III rectal cancer, to determine whether a survival paradox is present in our centre and assess for patient-related factors that can explain the observed paradox or were predictors of prognosis.METHODS:A retrospective review of data collected from 2006 to 2018 of patients diagnosed with rectal cancer in three separate centres was conducted. Percentages pertaining to patient and tumour characteristics, presentation, management and subsequent recurrence were reported. Preoperative and postoperative factors associated with survival were determined using univariable and multivariable logistic regression analysis.RESULTS:Stage IIB/C patients had significantly higher carcinoembryonic antigen (CEA) levels compared to stage IIA and stage IIIA patients (P < 0.001). Stage IIB/C patients had significantly larger primary rectal tumour and were more symptomatic (i.e. rectal bleeding, altered bowel habits and obstruction) at the time of diagnosis (P = 0.007). Preoperative CEA was an independent prognostic factor for cancer-specific survival in patients diagnosed with stage IIB/C and stage IIIA disease (P = 0.008) on multivariable analysis. Overall survival was greatest in stage IIIA disease, which was significantly greater than stage IIB/C disease.CONCLUSION:This study confirms the existence of a survival paradox in patients diagnosed with CRC in an Australian tertiary centre and adds further weight to the revision of the TNM staging to provide more emphasis on the T stage.

Background: Complex ventral hernias following laparotomy present a unique challenge in that repair is hindered by the lateral tension of the abdominal wall. A novel approach to overcome this is the "chemical component separation" technique. Here, botulinum toxin A (BTA) is instilled into the muscles of the abdominal wall. This induces flaccid paralysis and effectively reduces tension in the wall, allowing the muscles to be successfully joined in the midline during surgery. We describe a method where a large incisional hernia was repaired using this technique and review the variations in methodology. Case report: A woman in her mid-40s developed a ventral hernia in the setting of a previous laparotomy for a small bowel perforation. Computed tomography (CT) of the abdomen demonstrated an 85 (Width) × 95 mm (Length) ventral hernia containing loops of the bowel. Pre-operative botulinum toxin A administration was arranged at the local interventional radiology department. A total of 100 units of BTA were instilled at four sites into the muscular layers of the abdominal wall under CT-fluoroscopic guidance. She underwent an open incisional hernia repair 4 weeks later, where the contents were reduced and the abdominal wall layers were successfully joined in the midline. There was no clinical evidence of hernia recurrence at 3-months follow-up. Conclusion: Low-dose BTA effectively facilitates the surgical management of large ventral incisional hernias. There is, however, significant variation in the dosage, concentration and anatomical landmarks in which BTA is administered as described in the literature. Further studies are needed to assess and optimise these variables.

Background: The number of cases of rectal cancer in our older cohort is expected to rise with our ageing population. In this study, we analysed patterns in treatment and the long-term outcomes of patients older than 80 years with rectal cancer across a health district. Methods: All cases of rectal cancer managed at the Illawarra Cancer Care Centre, Australia between 2006 and 2018 were analysed from a prospectively maintained database. Patients were stratified into three age groups: ≤65 years, 66–79 years and ≥80 years of age. The clinicopathological characteristics, operative and non-operative treatment approach and survival outcomes of the three groups were compared. Results: Six hundred and ninety-nine patients with rectal cancer were managed, of which 118 (17%) were aged 80 and above. Patients above 80 were less likely to undergo surgery (71% vs. 90%, p < 0.001) or receive adjuvant/neoadjuvant chemoradiotherapy (p < 0.05). Of those that underwent surgical resection, their tumours were on average larger (36.5 vs. 31.5 mm, p = 0.019) and 18 mm closer the anal verge (p = 0.001). On Kaplan–Meier analysis, those above 80 had poorer cancer-specific survival when compared to their younger counterparts (p = 0.032), but this difference was no longer apparent after the first year (p = 0.381). Conclusion: Patients above the age of 80 with rectal cancer exhibit poorer cancer-specific survival, which is accounted for in the first year after diagnosis. Priority should be made to optimise care during this period. There is a need for further research to establish the role of chemoradiotherapy in this population, which appears to be underutilised.

Behcet's syndrome is a systemic inflammatory disorder that involves several organ systems and is exceptionally rare in the Western world. The diagnosis is frequently difficult as it resembles several other disease processes. A 23-year-old male with a previous presumptive diagnosis of Crohn's disease presented to our unit with genital ulceration. This is on a background of recurrent perianal abscesses requiring surgical drainage and seton placement. He subsequently developed a complex perianal fistula extending from the rectum to the perineum and left groin. After drainage and an unsuccessful trial of biologic immunosuppressive therapy, he developed several papulopustular cutaneous lesions and oral ulcerations. The diagnostic criteria for Behcet's syndrome was met and he was referred to a rheumatologist for ongoing management.

BACKGROUND:Neoadjuvant chemoradiotherapy plays a key role in reducing local recurrence rates for locally advanced rectal cancer. Pelvic magnetic resonance imaging (pMRI) is the gold standard for local clinical staging which allows clinicians to decide the treatment patients receive. A more advanced tumour or the presence of high-risk features on pMRI mean that neoadjuvant therapy will be offered to these patients. Understanding the accuracy of pMRI in local staging for rectal cancer is therefore crucial.METHODS:A retrospective cohort analysis of the accuracy of pMRI staging in a subgroup of patients who had primary rectal cancer surgery without neoadjuvant therapy was performed. Specificity and sensitivity for T-staging, N-staging and presence of high-risk features (threatened circumferential resection margin and extramural venous invasion) were calculated. Patients who had previous pelvic surgery, previous pelvic radiotherapy and previous surgery for continence were excluded.RESULTS:A total of 114 patients were included in the analysis. MRI accurately predicts T-stage in 56.6% and N-stage in 55.8%. Prediction of extramural disease was accurate in 51%. A negative circumferential resection margin was accurately predicted in 98.6% of patients. Overall adherence to reporting proforma was 15.8%.CONCLUSION:Overall, this study provided valuable information about the clinical staging of patients with rectal cancer who are at an early stage within a large regional catchment area in Australia with pMRI. These results allow us to assess the accuracy of our local staging with ramifications to the clinical decisions being made in the context of the more recent trials which questioned the need for neoadjuvant chemo-radiotherapy in all node positive patients.

Background The impact of increased body mass index (BMI) on clinical outcomes in locoregional rectal cancer is unknown. Methods This is a retrospective cohort study which included 453 consecutive rectal cancer patients undergoing definitive treatment, with confirmed stage I, II or III rectal adenocarcinoma. The association of BMI at diagnosis with overall survival (OS), cancer specific survival (CSS) and disease-free survival (DFS) was explored, controlling for key covariates using multivariable analyses. BMI as defined by the World Health Organization (WHO) is as follows: BMI <18.5-underweight; 18.5-24.9-normal; 25.0-29.9-pre-obesity; >30-obese. Results Overweight and obese patients had significantly better OS than underweight/normal weight patients (5-year OS 80% for overweight, 77% for obese, and 65% for underweight/normal weight patients, P=0.02). High BMI (>25) was significantly associated with improved OS in univariate [0.62 (0.4-0.8) P=0.007] and multivariable [0.65 (0.4-0.9) P=0.023] analyses. When stratified by stage, high BMI was associated with improved OS in stage III patients (P=0.0009), but not stage II (P=0.21) or stage I (0.54). High BMI was also significantly associated with improved CSS in univariate (HR 0.62, P=0.048) and multivariable analyses (HR 0.58, P=0.03). Conclusions In our study a BMI greater than 25 is significantly associated with a longer OS and CSS in patients with locoregional rectal cancer. These findings may be due to the reduced metabolic capacity for non-obese patients to deal with rectal cancer treatment as well as the burden of disease, however further research is needed to evaluate this.

Abstract Sacrococcygeal teratomas are rare congenital tumours that are even more uncommon when present in adulthood. They are derived from residual stem cells in the presacral space that differentiate into clusters of somatic cell. We present the diagnosis, management and post-operative follow-up in a 37-year-old gentleman referred to our department with an incidental finding of a lobulated presacral cystic mass on computed tomography imaging. Magnetic resonance imaging and fluorodeoxyglucose (FDG)-positron emission tomography (PET) scans were performed to further characterize the lesion. The decision was then made for surgical excision and the specimen along with the coccyx was retrieved en-bloc via a trans-sacral surgical approach. Histopathology of the mass uncovered the presence of squamous, respiratory and prostatic epithelium consistent with the diagnosis of a sacrococcygeal teratoma.

BACKGROUND:As treatments for rectal cancer improve with developments in surgical techniques, radiotherapy and chemotherapy, the nature of recurrences are evolving. We used a comprehensive database of a large Australian population with stage I-III rectal adenocarcinoma to identify timing and prognostic significance of recurrences, and factors associated with risk of developing recurrent disease.METHODS:All patients with locoregional rectal cancer treated with curative intent in our health district from 2006 to 2017 were included. Multivariate analysis using Cox regression models were used to identify factors associated with recurrence.RESULTS:A total of 483 patients were included. Recurrence occurred in 117 (24.2%) of 483 patients, being locoregional in 15 (3.1%) patients, distant in 85 patients (17.6%) and both locoregional and distant in 17 (3.5%) patients. Compared to those with locoregional recurrence, those with both locoregional and distant recurrence had worse cancer-specific survival. On univariate analysis, factors associated with recurrence included stage, grade, radiotherapy, chemotherapy, surgery type and distal tumour location. Factors which remained significant on multivariate analysis included higher grade and stage.CONCLUSION:In the era of multimodality therapy for rectal cancer, recurrences are predominantly distant. Traditional predictors including higher stage, grade and distal tumour location remain independently associated with recurrence, despite current treatment paradigms.

INTRODUCTION: Mixed adeno-neuroendocrine carcinoma (MANEC) is a rare disease, and much of the available literature to date has consisted of case reports. A recent systematic review revealed heterogeneity in the data as not all reports documented treatment regimens and course of disease. The recent 2019 WHO update on neuroendocrine carcinoma nomenclature adds to the pre-existing classification system based on biologic activity, to better represent the spectrum of neuroendocrine non-neuroendocrine tumours (Frizziero et al., 2020). PRESENTATION OF CASE: We present a case of a patient who presented with anal pain, had a wide local excision which on histopathology revealed poorly differentiated MANEC. Despite adjuvant chemotherapy with cisplatin and etoposide as well as pelvic radiotherapy, the patient developed bi-lobar liver metastases within 9 months of initial presentation. The patient succumbed to colonic perforation 10 months after initial presentation. DISCUSSION: Most patients present with advanced disease with site-specific symptoms, and despite treatment of localised disease, many recur with distant metastasis. CONCLUSION: Although rare, this disease is highly aggressive, thus it is hoped that more clinicians can be made aware about its various clinical manifestations and disease course. (C) 2020 The Author(s). Published by Elsevier Ltd on behalf of US Publishing Group Ltd.

The intestinal T-cell lymphomas are a rare group of lymphatic malignancies arising from the gastrointestinal tract. They frequently manifest with non-specific clinical and radiographic findings that may mimic several other disease processes. The most common subtype is linked with refractory coeliac disease and commonly affects the small intestine. We report a case where the diagnosis was uncovered endoscopically in a patient presenting with colonic perforation on a background of long-standing ulcerative colitis. Surgical source control was required prior to considering chemotherapy, which is the usual treatment option in lymphatic malignancies. The case highlights the importance endoscopic evaluation in inflammatory conditions of the colon.

We describe a practical approach to the management of complex anal fistula in an immunocompromised patient. We define our treatment motifs: to close the internal opening, maintain external drainage until internal opening and tract healed; minimize sphincter damage. We hope other authors can build on this case technique to improve fistula surgery outcomes.

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678 Background: There is limited information on outcomes in elderly patients with rectal cancer as they are often excluded from clinical trials. This study aimed to assess treatment patterns and outcomes in these patients. Methods: We utilised data from electronic records to identify patients aged ≥ 70 years with a histological diagnosis of rectal cancer from 2006-2015, treated in the South Western Sydney and Illawarra Shoalhaven Local Health Districts, Australia. Treatment modalities, recurrence and survival data were analysed. Results: We identified 942 patients with rectal cancer, with median follow-up of 3.4 years. 393 patients (42%) were aged ≥ 70 years. Median age of this cohort was 77 years (range 70–96 years). Elderly patients were more likely to present with locoregional disease (stage I-III, 83% vs. 75%) and more likely to receive palliative treatment only (21% vs. 16%, p = 0.0005). Of 704 patients who received treatment with curative intent, 300 (43%) were ≥ 70 years. Although clinicopathological features were similar between elderly and young patients, patients ≥ 70 years were more likely to be treated with surgery alone (56% vs. 28%, p < 0.0001), less likely to receive neoadjuvant (25% vs. 44%, p < 0.0001) or adjuvant treatments (29% vs. 55%, p < 0.0001), or be discussed in a multidisciplinary meeting (51% vs. 61%, p = 0.001). Compared to younger patients, elderly patients had a significantly poorer overall survival (HR 2.9, 95% CI 2.2 – 3.7, p < 0.0001). There were no significant differences in cancer specific survival (HR 1.4, 95% CI 0.98 – 2.0, p = 0.06) or relapse free survival (HR 0.92, 95% CI 0.7 – 1.2, p = 0.60). Conclusions: Although more elderly patients were treated with palliative intent compared to younger patients, the majority of elderly rectal cancer patients were still treated with curative intent. Most had surgery alone. Uptake of neoadjuvant and adjuvant therapy, as well as multidisciplinary involvement, was lower. Elderly patients had similar cancer-specific outcomes compared to younger patients, supporting curative intent treatment in these patients. Further analyses are underway to identify subgroups in the elderly population who benefit from trimodality therapy, and potential differences in their disease biology.

We present the case of an 80-year old man taking rivaroxaban for atrial fibrillation who sustained massive intra-abdominal bleeding in the setting of acute cholecystitis. CT scan on admission revealed evidence of active bleeding into the gallbladder lumen and gallbladder perforation. Immediate resuscitation was commenced with intravenous fluids, antibiotics and blood products. Despite attempts to correct coagulopathy, the patient's haemodynamic status deteriorated and an emergency laparotomy was performed, with open cholecystectomy, washout and haemostasis. The patient had a largely uneventful recovery and was discharged on day 11 of admission. Patients with coagulopathies, whether pharmacological or due to underlying disease processes, are at very high risk of severe haemorrhagic complications and subsequent morbidity. As such, prompt recognition and operative management of haemorrhagic perforated cholecystitis is of crucial importance.

ANZ Journal of SurgeryVolume 89, Issue 10 p. E472-E473 IMAGES FOR SURGEONS Rare case of delayed onset colitis due to immunotherapy for malignant melanoma Mina Sarofim BMed, MD, Mina Sarofim BMed, MD orcid.org/0000-0003-3808-0774 Department of Colorectal Surgery, Wollongong Hospital, Sydney, New South Wales, Australia The University of New South Wales, Sydney, New South Wales, AustraliaSearch for more papers by this authorRobert Winn BSc, MBBS, FRACS, Robert Winn BSc, MBBS, FRACS Department of Colorectal Surgery, Wollongong Hospital, Sydney, New South Wales, AustraliaSearch for more papers by this author Mina Sarofim BMed, MD, Mina Sarofim BMed, MD orcid.org/0000-0003-3808-0774 Department of Colorectal Surgery, Wollongong Hospital, Sydney, New South Wales, Australia The University of New South Wales, Sydney, New South Wales, AustraliaSearch for more papers by this authorRobert Winn BSc, MBBS, FRACS, Robert Winn BSc, MBBS, FRACS Department of Colorectal Surgery, Wollongong Hospital, Sydney, New South Wales, AustraliaSearch for more papers by this author First published: 22 August 2018 https://doi.org/10.1111/ans.14768Citations: 6Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume89, Issue10October 2019Pages E472-E473 RelatedInformation

ANZ Journal of SurgeryVolume 88, Issue 9 p. E685-E686 IMAGES FOR SURGEONS Pseudomembranous colitis presenting as a mechanical large bowel obstruction Katherine J. Zhu MBBS, FRACS (General Surgery), Katherine J. Zhu MBBS, FRACS (General Surgery) Department of General Surgery, Wollongong Hospital, Wollongong, New South Wales, AustraliaSearch for more papers by this authorRobert Winn BSc, MBBS, FRACS (General Surgery), Robert Winn BSc, MBBS, FRACS (General Surgery) Department of General Surgery, Wollongong Hospital, Wollongong, New South Wales, AustraliaSearch for more papers by this author Katherine J. Zhu MBBS, FRACS (General Surgery), Katherine J. Zhu MBBS, FRACS (General Surgery) Department of General Surgery, Wollongong Hospital, Wollongong, New South Wales, AustraliaSearch for more papers by this authorRobert Winn BSc, MBBS, FRACS (General Surgery), Robert Winn BSc, MBBS, FRACS (General Surgery) Department of General Surgery, Wollongong Hospital, Wollongong, New South Wales, AustraliaSearch for more papers by this author First published: 25 July 2016 https://doi.org/10.1111/ans.13679Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume88, Issue9September 2018Pages E685-E686 RelatedInformation

BACKGROUND:Colorectal cancer (CRC) pathological reporting deficiencies have been shown to be common, with deviations from the suggested minimum dataset. Information from both surgeon and pathologist is necessary for a complete report. These deficiencies have been shown to be correctable with the use of synoptic reporting. We carried out an audit on a random sample of CRC pathological reports from the first 6 months of 2004 in Victoria, Australia, with the aim of documenting current CRC pathological reporting deficiencies.METHODS:A random sample of pathological reports for CRC was obtained from the Cancer Council of Victoria. One hundred and sixteen of these reports were reviewed by a team of surgical and pathology trainees. Presence or absence of the various fields of the 1999 National Health and Medical Research Council minimum dataset for CRC reporting was recorded.RESULTS:There were deviations from the minimal dataset. Most notable was the absence of the information on the apical node, the presence of distant metastasis and perineural invasion.CONCLUSIONS:The opportunity exists for improvement in the pathological reporting of CRC in Victoria through the uniform introduction of synoptic reporting.

Triple energy window (TEW) scatter correction estimates the contribution of scattered photons to the acquisition data by acquiring additional data through two narrow energy windows placed adjoined to the main (photopeak) energy window. The contribution is estimated by linear interpolation and then subtracted. Noise amplification is reduced by filtering both the photopeak scintigram and the scatter estimate. We have studied the filter settings of each filter using a physical phantom filled with a 201Tl-solution resulting in count densities comparable to clinical studies. The performance of order-8 Butterworth filters at different cut-off frequencies (CoFs) were compared based on signal to noise ratios (SNRs). The highest SNRs were obtained when the noisy scatter information was strongly filtered with the CoF less than or equal to 0.07 cycles/pixel (cpp). The best CoF for the filter of the photopeak image is object size dependent; smaller objects require a higher CoF. For objects with a size near the SPECT spatial resolution (approximately 15 mm) the optimal CoF is equal to 0.18 cpp. For larger objects (31.8 mm) the highest SNR was obtained with a CoF equal to 0.13 cpp. A CoF equal to 0.16 cpp is a good compromise for all objects with a diameter equal to the spatial resolution or larger. These results depend on the initial signal to noise ratio of the acquisition data and so on the count density.