Hereditary diffuse gastric cancer (HDGC) is a rare cancer representing between 1-3% of the 2000 gastric cancer diagnoses in Australia in 2010. HDGC is caused by germline mutations to the CDH1 gene and is an autosomal dominant inherited cancer with high penetrance rates. Known carriers of the CDH1 germline mutation are advised to undergo a prophylactic gastrectomy. This procedure is recommended in carriers in early adulthood and completely eliminates the risk of gastric cancer. However, it conveys a number of significant nutritional implications. Current literature suggests that global quality of life scores return to pre-operative levels at around 12 months post-operatively, although there are ongoing issues beyond this that can have a significant impact on people’s lives. This group of patients are predominantly well pre-operatively however can experience a number of issues post-operatively, in the immediate and longer term. These include, but are not limited to, significant weight loss, dumping syndrome, lactose intolerance, steatorrhoea, anastomotic strictures and nutritional deficiencies.
A pilot study conducted at Peter MacCallum Cancer Centre with 9 patients who underwent a prophylactic gastrectomy for a CDH1 gene mutation found that all patients had lost significant weight 3 months post-operatively (mean loss of body weight = 17%), experienced symptomatic dumping syndrome and discomfort with eating. A majority of patients experienced their worst symptoms in the first 3 months post-operatively, but some symptoms didn’t develop until 12 months post-operatively. The majority (78%) reported they fatigued more easily compared to pre-operatively, with an average of 9 months before patients returned to pre-operative energy levels, however there was minimal impact on social activities.
Routine peri-operative dietitian involvement with this small but high risk group of patients is essential to facilitate positive longer term outcomes and reduce the risk of malnutrition resulting from post-operative symptoms and weight loss.