Alex Ng

Incidence of Malignant Melanoma in Auckland, New Zealand: Highest Rates in the World

Abstract. The calculation of incidence rates of melanoma in New Zealand has been hampered in the past by incomplete registration of cases. The aim of this study was to document the incidence of melanoma in the Auckland Caucasian population and to define the pathologic characteristics of these lesions. Data were collected for the Auckland region from the New Zealand Cancer Registry and the Auckland Melanoma Unit database for 1995 and combined with census statistics to give the crude and age-standardized rates for invasive melanoma. The results were analyzed by gender, morphology, body site, and thickness. The crude annual incidence for invasive cutaneous malignant melanoma was 77.7/100,000. The age-standardized annual rate was 56.2/100,000 with no statistically significant differences in the rates for males and females. The cumulative risk of developing melanoma over a lifetime, from age 0 to 74, was 5.7% overall. The age-specific rates steadily increase with advancing age. The lesions were generally thin; 64% were less than 0.76 mm, and only 7% were thicker than 3.00 mm. In conclusion, the Caucasian population in the Auckland region has the highest incidence of melanoma in the world.

Predicting Hollow Viscus Injury in Blunt Abdominal Trauma with Computed Tomography

BackgroundEvaluation of blunt abdominal trauma is controversial. Computed tomography (CT) of the abdomen is commonly used but has limitations, especially in excluding hollow viscus injury in the presence of solid organ injury. To determine whether CT reports alone could be used to direct operative treatment in abdominal trauma, this study was undertaken.MethodsThe trauma database at Auckland City Hospital was accessed for patients who had abdominal CT and subsequent laparotomy during a five-year period. The CT scans were reevaluated by a consultant radiologist who was blinded to operative findings. The CT findings were correlated with the operative findings.ResultsBetween January 2002 and December 2007, 1,250 patients were evaluated for blunt abdominal injury with CT. A subset of 78 patients underwent laparotomy, and this formed the study group. The sensitivity and specificity of CT scan in predicting hollow viscus injury was 55.33 and 92.06xa0% respectively. The positive and negative predictive values were 61.53 and 89.23xa0% respectively. Presence of free fluid in CT scan was sensitive in diagnosing hollow viscus injury (90xa0%). Specific findings for hollow viscus injuries on CT scan were free intraperitoneal air (93xa0%), retroperitoneal air (100xa0%), oral contrast extravasation (100xa0%), bowel wall defect (98xa0%), patchy bowel enhancement (97xa0%), and mesenteric abnormality (94xa0%).ConclusionsCT alone cannot be used as a screening tool for hollow viscus injury. The decision to operate in hollow viscus injury has to be based on mechanism of injury and clinical findings together with radiological evidence.

IS EXPLORATION MANDATORY IN PENETRATING ZONE II NECK INJURIES

Background:u2003 A policy of mandatory neck exploration for zone II injuries deep to platysma was promoted in the 1950s and was associated with a reduction in mortality when compared with expectant or delayed exploration. Recently many trauma centres have been practising selective neck exploration using physical examination and imaging to stratify patients to different management strategies. In the Auckland region, patients with penetrating zone II injury deep to platysma have been managed with mandatory neck exploration. As penetrating injuries in the Auckland region are caused by a range of sharp objects, with gunshot wounds rare, outcomes of management of zone II neck injuries in this population warrant investigation. The aim of this study was to determine the rate of therapeutic neck exploration in patients with penetrating zone II neck injury in the Auckland region and to suggest optimum management strategies for such injuries.

Penetrating thoraco-abdominal injuries: the Auckland City Hospital experience

Background:u2002 Penetrating injuries to the thoraco‐abdominal region are rare in New Zealand. Most are low velocity wounds and are managed by general surgeons. However, injuries to major vascular structures and the heart are best managed by a multidisciplinary approach.

Surgical treatment of early stage breast cancer in the Auckland and Waikato regions of New Zealand: Surgery for breast cancer in NZ

The aim of this study was to understand the factors influencing the use of surgical options by New Zealand women with newly diagnosed breast cancer.

Examination under anesthesia prior laparoscopic appendicectomy: does it change the approach?

The clinical finding of a mass in the right iliac fossa during the course of diagnosis of acute appendicitis may affect the management approach. A mass is sometimes only evident when the abdomen is examined under anesthesia. This study was conducted to assess the significance of examination under anesthesia and analyze the outcome of laparoscopic exploration and its correlation with the finding of a mass that can be felt only under anesthesia. We conducted a prospective study over 12 months on patients diagnosed with acute appendicitis who were treated with laparoscopic approach. There were 179 patients (101 females) who underwent laparoscopic appendicectomy; 20 cases (11%) were converted to open appendicectomy. Examination under anesthesia revealed a mass in 20 patients (11%). The rate of conversion to open operation was 65% (13 patients) in those who had palpable mass and 4% (7 patients) in those who had no mass (P<0.0001). This study has shown that most patients with a mass found under anesthesia will need conversion of the laparoscopic procedure to an open operation. The recommendation from this study therefore is that all patients planned to have a laparoscopic appendicectomy should have examination under anesthesia; if a mass is found, then the procedure should be converted to open operation from the beginning.