Parenteral Nutrition Prolongs the Survival of Patients Associated With Malignant Gastrointestinal ObstructionFrom the Department of Surgery, Wenzhou Medical College, Taizhou Hospital, Zhejiang, China Correspondence: Bo-Guang Fan, MD, PhD, Department of Surgery, Taizhou Hospital of Zhejiang Province, Taizhou Linhai, Zhejiang Province, China. Electronic mail may be sent to fanboguang{at}gmail.com.
Background: Many patients with advanced cancers have associated
gastrointestinal (GI) obstruction. Parenteral nutrition (PN) is indicated in
patients with a dysfunctional GI tract, but the role of PN in patients'
survival is still controversial. The present study was retrospectively
conducted to verify if there are any long-term survivors living for more than
1 year after initiation of PN without food or drink in patients with malignant
GI tract obstruction resulting from advanced cancers. Methods: One
hundred fifteen adult patients with malignant GI obstruction were identified
over a 6-year period at a palliative-care setting. Their median age was 51
years (range, 31–74 years), and 62 (54%) were women and 53 men (46%).
All selected patients had malignant GI tract obstruction and started PN
treatment after cessation of energy intake to time of death. Survival
expectancy as a criterion was analyzed in all patients. Results: The
median time from initiation of PN to death was 6.5 months. Eleven patients
survived Patients with advanced cancers are frequently associated with many different complications, including gastrointestinal (GI) obstruction, which results from the spread of primary cancer, infiltration of the bowel by tumor, and adhesions. For those with malignant GI tract obstruction, parenteral nutrition (PN) is the only source of nutrition.1 However, the role of PN in patients with advanced cancers has been controversial, especially in improvement of patients' survival,2–6 but in many countries the patients receiving PN live an extended life,3–5 and PN seems to be effective for malnutrition in cancer patients. The purpose of the present study, therefore, was to explore life expectancy in the patient with advanced cancer who received PN after cessation of energy intake due to malignant GI tract obstruction. Survival period after cessation of energy intake is only a few months.7 The present article reports whether there are any long-term survivors living for more than 1 year after initiation of PN without any food or drink intake.
This study was retrospectively conducted in a single palliative-care unit, with PN initiated between 2000 and 2006 at a single institution. All patients must have a consultation with the Parenteral Nutrition Center at the hospital before initiation of PN, and 3 doctors were responsible for determining if patients were candidates for PN. All patients had to obtain the same opinion from at least 2 of the 3 doctors and meet the following criteria to be included in the study: a diagnosis of advanced cancer (ie, locally or distantly recurrent, or metastatic malignancy) and cessation of food intake due to malignant GI tract obstruction, with no chance to be cured by a surgical or other procedure. In all patients, different interventions were first attempted to allow enteral nutrition (EN) beyond obstructions; only those who could not accept EN were selected for PN therapy. Each patient was considered on an individual basis and was required be more than 18 years old, with an estimated life expectancy longer than a few months. Survival period was measured in months, starting from the date of PN to the time of death. Those unwilling to continue PN and who had PN-related complications, such as line sepsis, central venous thrombosis, and liver disease, were not included in the study. The following data of all eligible patients were recorded: age at the time of PN initiation, sex, information of oncological status (ie, diagnosis of primary cancer and site of metastasis), date of cessation of food intake, date of initiation and cessation of PN, whether weight loss occurred before initiation of PN, and date of death. One hundred fifteen patients, including 62 women (54%) and 53 men (46%), were identified in the present study. Their mean age at the initiation of PN was 51 years (range, 31–74 years). The most common type of cancer was GI malignancies, and the liver was the most common site of metastasis (Table I).
PN was administered via a central venous port, typically provided
at 30 ± 2 kcal/kg/d, 0.3 ± 0.05 g nitrogen per kg per day. PN
was provided as an "all-in-one" administration, which included
glucose, fat, amino acids (Table
II), and additives such as vitamins, minerals, and trace elements
continuously infused over 12–18 hours until death. A survival period
Before initiation of PN, all patients had weight loss (9 kg on average). Mean time from the initiation of PN to death was 6.5 months, but 11 patients survived more than 12 months. For all patients, the date of PN cessation was virtually the same as the date of death, and death was the reason for PN cessation. Noteworthy were 11 patients who lived 16 months (range, 14–20 months) after cessation of energy intake. Two exceptional cases are 1 patient with colonic carcinoma, who has lived for 42 months after PN; and another patient with sarcoma, who stopped and restarted PN and has overall lived for almost 4 years. The 2 patients are still alive and continue receiving PN; their data were not included in this study.
For patients with advanced cancers, especially for those without an opportunity to be cured, either adjunctive management or conservative treatment has been chosen as a purpose to prolong patients' survival. PN is indicated in patients who no longer have a functional GI tract,1 but the role of PN in patients with incurable-stage or advanced malignancies has been conflicting.2–6 GI obstruction is a major complication in advanced cancer.8 The main criterion of the use of PN in the present study was GI obstruction due to advanced malignancies. The advanced malignancy was defined as locally or distantly recurrent or metastatic malignancy and was incurable through a surgical or other clinical procedure. All subjects in the present study received their treatment in palliative-care wards. The present study examined the effects of PN on advanced-cancer-bearing patients' survival. The survival period in the patient with advanced cancer is related to many factors, including the type of cancer, site of metastasis, patient's general information,9 and the side effects related to PN therapy.10 When studying patients' record for this article, we found that in the total 132 cases searched, 14 cases were associated with line sepsis and 3 patients died of PN-related liver disease. This is similar to other reports in that some individuals have no PN-related side effects, whereas others may have experienced significant morbidities.10 The present study, however, excluded the patients with PN-related complications; the life expectancy was analyzed without an influence of those complications. In addition, long-term survivorship was analyzed not according to the type of cancer and site of metastasis, because the number of different types of individual cancers was not enough to reflect meaningful analysis. A previous study reported that cessation of food intake in a noncancer "healthy" population was usually associated with a life expectancy of only a few months.7 The present study was completed in terminal-stage cancer patients and showed that most patients lived well beyond a few months; 11 patients lived even >12 months. Two patients are still alive at the time of the current study and have been receiving PN for more than 3 years. Comparing the previous report with our result, the finding that long-term survival was seen in the present study suggests that PN can be a lifesaving and life-sustaining intervention for patients with advanced cancer. This is in agreement with another study, which indicated that PN was associated with a long-term survival in incurable cancer patients.11 Explanation of the findings of some patients surviving a long time was an important finding in this study. However, it is hard to explain the exact reasons why some patients survived longer, whereas other did not, because the small number of only 115 patients in the present study did not allow conclusions about what affected the survival, and the patients presented nothing with predicative factors that were significantly associated with improved survival. On the other hand, there are a number of possible explanations or mechanisms of improvement in survival. Patients receiving PN experienced prolonged survival, which was accompanied by improved energy balance, increasing body fat, and a greater maximum exercise capacity.12 Thus, those factors may improve the survival period. The PN formulas used in the present study seem somewhat aggressive in the amount of calorie and protein provision for these patients with "terminal" stages of cancers. In fact, a simple explanation for observations made in weight-losing patients with malignant disease is that inefficient organisms consume more energy during rest, as well as motion.13 Therefore, increased energy efficiency should translate to less pronounced wasting of host tissue.13 Moreover, in considering if there was the possibility of exacerbating tumor growth during PN described in the present study, while much attention was paid to maintain patients' energy efficiency and body weight, no potential evidence of stimulating tumor growth by using PN was found in the present study. All patients in the present study were in the palliative care setting and already had weight loss before initiation of PN. The cause of the weight loss may be related to mechanical GI problems, such as bowel obstruction or malabsorption. Anorexia is often cited as a primary cause of weight loss in patients with metastatic diseases.14 There are several studies describing the effect of PN on quality of life in advanced or incurable cancer patients.1,12,15 Some studies have clearly shown improvement in quality of life,16,17 and PN was shown to be beneficial for patients' survival.11 More recent evidence advocated early supplementation of PN in terminal-stage cancer patients in order to stabilize body protein status or anabolic balance.12 The main goal of PN is to maintain or restore the patient's nutrition status and to correct or prevent malnutrition-related symptoms.17 For patients with GI obstruction, PN is the only source of nutrition and energy and may improve their quality of life.1 Thus, PN is associated with long-term survival. The potential role of PN support in palliative care can be tested in several different ways. The present study selected survival period as a criterion to examine if there was a role for PN in advanced cancer patients. The result of the present study concludes that PN can be expected to obtain a longer survival period for the patient associated with GI obstruction caused by advanced cancer. Received for publication February 18, 2007. Accepted for publication April 23, 2007.
Journal of Parenteral and Enteral Nutrition, Vol. 31, No. 6,
508-510 (2007)
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1 year and 2 patients have been alive for almost 4 years later
after cessation of energy intake. Conclusions: PN can be expected to
obtain a longer survival for the patient with GI tract obstruction caused by
advanced cancer. 
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MATERIALS AND METHODS
RESULTS