No abstract

Body composition measurement using diagnostic computed tomography (CT) scans has emerged as a method to assess sarcopenia (low muscle mass) in oncology patients. Assessment of skeletal muscle mass (SMM) using the cross-sectional area (CSA) of a single vertebral slice (at lumbar L3) in a CT scan is correlated to whole body skeletal muscle volume. This method is used to assess CT-defined sarcopenia in patients with cancer, with low SMM effecting outcomes. However, as diagnostic scans are based on tumour location, not all include L3. We evaluated the evidence for the use of alternate vertebral CT slices for SMM evaluation when L3 is not available. Five electronic databases were searched from Jan 1996-April 2020 for studies using CT scan vertebral slices above L3 for SM measurement in adults with cancer (solid tumours). Validation with whole body SMM, rationale for the chosen slice, and sarcopenia cut-off values were investigated. Thirty-two studies were included, all retrospective and cross-sectional in design. Cervical, thoracic, and lumbar slices were used (from C3-L1), with no validation of whole body SMM using CT scans. Alternate slices were used in lung, and head and neck cancer patients. Sarcopenia cut-off values were reported in 75% of studies, with differing methods, with or without sex-specific values, and a lack of consensus. Current evidence is inadequate to provide definitive recommendations for alternate vertebral slice use for SMM evaluation in cancer patients. Variation in sarcopenia cut-offs warrants more robust investigation, in order for risk stratification to be applied to all patients with cancer.

Critical weight loss (CWL) defined as ≥5% in one month, is common in patients with oropharynx cancer and identification of patients at risk is challenging. We aimed to investigate if predictors of CWL in this population exist to guide nutritional intervention. Data were collected retrospectively on 134 patients who had radiotherapy (RT) ± concurrent chemotherapy (CRT) ± surgery. Body weights were collected pre-RT and during RT, with percentage weight change measured against baseline. Logistic regression was used to analyze chosen predictors. The incidence of CWL was 67% (26% of these patients experiencing ≥10% loss). Patients who had CRT experienced significantly higher weight loss (7.1% versus 4.7%; p = 0.001). Tube feeding was used in 64% of patients with CWL, the majority of tubes inserted reactively. These patients had a mean weight change of -8.8% (versus -7.1% in those with no tube) (p = 0.004). Multivariate models identified increased risk of CWL in tonsil origin tumors (p < 0.05), with CRT being the only predictor of weight loss ≥10% (p < 0.05). These patients are particularly vulnerable to CWL and the majority experience significant nutritional issues during RT, regardless of nutritional status at diagnosis. Nutritional intervention should be targeted accordingly.

Enteral feeding is often required for nutrition support in head and neck cancer patients when oral intake is inadequate. When to initiate the insertion of a feeding tube continues to be a debated issue in our institution. We investigated the use of reactive feeding tubes (RFTs) in patients with advanced stage oropharynx cancer (OPC). Data were retrospectively collected on 131 patients who had radiotherapy (RT) ± chemotherapy from 2005 to 2015. Predictors for RFT insertion were investigated. Weight loss during RT was compared between those with RFT versus prophylactic tubes (PFTs) versus no tube, and survival outcomes evaluated. RFTs were more likely to be needed in patients who had bilateral neck node irradiation (p = 0.001) and concurrent chemoradiotherapy (CRT) (p = 0.038). Patients with RFTs had significantly higher mean percentage weight loss during RT (9.5 ± 3.4%) (p < 0.001) when compared to those with a PFT (5.2 ± 4.7%) and those with no tube (5.4 ± 3.1%). No difference was seen in 5-year survival rates in patients who did not have a feeding tube to those who required a RFT. RFT use is frequent in OPC, although difficult to predict. CRT and bilateral neck node irradiation were found to be associated with the need for the insertion of a feeding tube during RT. These patients also experience significantly higher weight loss, therefore, prophylactic tubes may need to be considered more often in this population.