Development of an Esophageal Cancer-specific Nutrition Impact Symptom Scale for Individualized Postoperative Nutritional Nursing

Summary

This study developed the Nutrition Impact Symptom–Esophageal Cancer scale (NIS-EC) and tested its use for symptom-guided nutritional nursing after esophageal cancer surgery. NIS-EC-guided care reduced symptom burden, improved nutritional indicators and protein intake, lowered complications, and shortened hospital stay.

Abstract

This study aimed to develop and preliminarily validate the Nutrition Impact Symptom–Esophageal Cancer scale (NIS-EC) and evaluate its clinical use for individualized postoperative nutritional nursing. This two-stage study included scale development/preliminary psychometric evaluation, followed by clinical application. In stage I, items were generated from a literature review, the Theory of Unpleasant Symptoms, two rounds of Delphi consultation, and pilot testing. Thirty clinically stable patients with esophageal cancer completed the NIS-EC for item analysis, reliability testing, validity assessment, and 14 ± 2 day retesting. In stage II, an unblinded single-arm phase II supportive-care study with a non-concurrent historical-control comparison was conducted among 107 patients after radical surgery for esophageal cancer. Fifty-seven patients received NIS-EC-guided individualized nutritional nursing, whereas 50 historical controls received routine postoperative nutritional nursing. Outcomes were assessed at baseline and 4 weeks. The final NIS-EC contained 22 items in three domains: digestive tract symptoms, malaise-related symptoms, and psychological-emotional symptoms. The scale showed good internal consistency, with a Cronbach’s alpha of 0.921, split-half reliability of 0.904, and test-retest reliability of 0.913. Content and structural validity were acceptable, and the total score correlated with PG-SGA score (r = 0.784, P < 0.001). At week 4, the intervention group had lower NIS-EC scores, greater improvements in BMI, albumin, prealbumin, and hemoglobin, higher attainment of protein intake targets, fewer postoperative complications, and a shorter postoperative hospital stay than historical controls (P < 0.05). In conclusion, the NIS-EC provides preliminary, reliable, and valid symptom profiling in esophageal cancer. NIS-EC-guided nutritional nursing may support postoperative symptom control and nutritional recovery, but multicenter randomized controlled trials are required to validate these findings.

Introduction

Esophageal cancer (EC) is frequently accompanied by malnutrition because of tumor obstruction, treatment-related symptoms, and postoperative anatomical changes that can restrict oral intake. Malnutrition and impaired intake in EC are associated with poorer treatment tolerance, delayed recovery, reduced quality of life, and unfavorable prognosis^1,2,3. Nutrition impact symptoms (NIS) are symptoms that compromise a patient’s desire or ability to eat, interfere with nutritional requirements, and increase the risk of malnutrition, loss of lean body mass, and impaired quality of life^4,5,6. In patients with EC, relevant symptoms include dysphagia, choking during feeding, reflux, nausea and vomiting, early satiety, taste or smell alteration, fatigue, pain, sleep disturbance, and psychological distress⁷. These symptoms may occur before treatment and can persist after surgery and during rehabilitation; therefore, longitudinal symptom profiling needs to be disease-specific rather than borrowed directly from generic nutritional screening⁸.

Postoperative nutritional care after EC surgery must target adequate energy and protein intake together⁹. Energy intake provides the metabolic substrate required for recovery, whereas adequate protein intake supports wound healing, immune function, and preservation of lean body mass¹⁰. Protein intake should therefore not be interpreted separately from total energy intake; in the present study, protein intake target attainment was selected as a pragmatic clinical outcome because of its relevance to surgical recovery, but the intervention was designed to improve overall dietary intake by addressing the symptoms that limited eating¹¹.

Existing nutritional assessment instruments do not fully meet this need, and the PG-SGA remains useful for nutritional risk and global nutritional status, but its symptom component is not designed to characterize the EC-specific symptom pattern or to guide item-level nursing intervention¹². Symptom inventories for gastrointestinal cancer assess symptom burden more broadly, while the head-and-neck cancer nutrition impact symptom checklist provides an important methodological reference, but cannot be assumed to cover the swallowing, reflux, postoperative diet-transition, and thoracic surgery-related symptom profile of EC¹³. This gap justified the development of an EC-specific NIS scale.

To address this clinical gap, the present study drew on the Theory of Unpleasant Symptoms, which links symptom experience with influencing factors and functional outcomes, and focused on symptom targets that interfere with oral energy and protein intake in patients with EC. The work was carried out in two linked stages: in the first stage, an EC-specific NIS scale was developed and preliminarily evaluated; in the second stage, the scale was applied to guide individualized postoperative nutritional nursing, and early clinical outcomes were compared with those of a non-concurrent historical-control group receiving routine nutritional nursing. This design was used to examine feasibility and early clinical signals after implementation of the scale-guided pathway, rather than to claim the level of evidence of a randomized controlled trial.

Protocol

Study subjects

All participants in this study were patients with primary EC admitted to the Affiliated Hospital of Nantong University between April 2024 and August 2025. The study was approved by the Ethics Committee of the Affiliated Hospital of Nantong University (Approval No. 2026-K113-01), and all participants provided informed consent.

Study design and timeline

This work consisted of two linked stages: Stages I and II. Stage I was a scale development and preliminary psychometric evaluation study: the first assessment was conducted when patients were clinically stable and able to complete the questionnaire. The retest assessment was performed 14 ± 2 days later, either during the same admission or at a scheduled outpatient follow-up visit. Patients with major clinical deterioration or a change from oral intake to complete enteral or parenteral nutritional support between the two assessments were excluded from the test-retest analysis.

Stage II was an unblinded single-arm phase II supportive-care study with a non-concurrent historical-control comparison: historical controls were patients treated before routine implementation of the NIS-EC-guided pathway and received routine postoperative nutritional nursing, and the intervention group was recruited after implementation of the scale-guided pathway. The baseline assessment was conducted after transfer to the thoracic surgery ward, when planning for oral or enteral intake began. A follow-up assessment was performed 4 weeks after surgery. Patients discharged before week 4 completed dietary records and scale reassessment at outpatient or telephone follow-up. The inclusion criterion concerning nutritional support referred to an expected need for postoperative nutritional management and follow-up for at least 4 weeks, rather than a continuous inpatient stay.

Stage I: Reliability and validity validation study of the NIS-EC scale

Inclusion criteria: patients with primary EC confirmed by postoperative histopathology, including squamous cell carcinoma and adenocarcinoma, and meeting the diagnostic criteria of the Chinese Guidelines for the Diagnosis and Treatment of Esophageal Cancer (2022 edition); age 18–80 years, with no restriction on sex; ability to eat orally without the need for complete enteral or parenteral nutritional support; clear consciousness, normal speech, hearing, reading, and writing abilities, and the ability to complete the questionnaire independently or under investigator guidance; voluntary provision of informed consent and ability to complete two rounds of scale assessment.

Exclusion criteria: other primary malignant tumors; severe failure of major organs such as the heart, liver, or kidneys, severe infection, massive gastrointestinal bleeding, or other critical complications; cognitive dysfunction, a history of mental illness, or communication disorders that precluded completion of the assessment; esophageal fistula or complete gastrointestinal obstruction requiring full enteral nutrition via a nasogastric tube or jejunostomy tube; participation in other clinical studies related to nutritional intervention or symptom management; withdrawal midway or loss to follow-up.

Stage II: Prospective cohort study for clinical application validation

The inclusion criteria were as follows: primary EC confirmed by histopathological examination and meeting the diagnostic criteria of the Chinese Guidelines for the Diagnosis and Treatment of Esophageal Cancer (2022 edition); age 18–80 years, with no restriction on sex; first radical surgery for EC (thoracoscopic or open approach), followed by transfer to the thoracic surgery ward for continued treatment; ability to eat orally or receive partial enteral nutritional support, with an expected need for postoperative nutritional management and follow-up for at least 4 weeks; clear consciousness and ability to complete the full assessment and follow-up process; voluntary provision of informed consent. Exclusion criteria: severe preoperative malnutrition (PG-SGA score ≥ 9) or cachexia; other primary malignant tumors or severe failure of major organs such as the heart, liver, and kidneys; neoadjuvant radiotherapy or chemotherapy before surgery; severe postoperative complications such as anastomotic leakage, chylothorax, or severe pulmonary infection requiring transfer to the intensive care unit or complete fasting; cognitive dysfunction or a history of mental illness preventing participation in the study; withdrawal midway, transfer to another hospital, or loss to follow-up.

Research instruments

NIS-EC

This scale was developed in the present study based on the Theory of Unpleasant Symptoms. A formal version was established after a systematic literature review, two rounds of Delphi consultation involving 15 experts, and pilot optimization in 30 patients. The final NIS-EC contains 3 core dimensions and 22 items in total, including 10 items in the gastrointestinal symptom dimension, 5 items in the malaise-related symptom dimension, and 7 items in the psychological-emotional symptom dimension (Supplemental Table S1). Each item is assessed from three aspects: symptom frequency, symptom severity, and interference with eating or protein intake. Each aspect is scored from 0 to 4, yielding an item score of 0 to 12. The total score is the sum of all item scores across the 3 subdimensions, ranging from 0 to 264 points. A higher score indicates a heavier burden of nutrition impact symptoms and greater interference with protein intake and overall nutritional status.

PG-SGA

This scale was developed by Ottery in 1994, with a Cronbach’s α coefficient of 0.89 and a content validity index of 0.92, indicating good reliability and validity¹⁴. The scale consists of two parts: patient self-assessment and assessment by medical staff. The self-assessment section includes weight change, food intake, symptoms interfering with eating, and activity level, whereas the medical staff section covers disease status, metabolic stress, and physical examination. The total score ranges from 0 to 35 points, with 0–1 indicating good nutritional status, 2–8 indicating moderate or suspected malnutrition, and ≥9 indicating severe malnutrition. A higher score reflects greater nutritional risk and more severe malnutrition.

General information questionnaire

This questionnaire was designed by the research team based on a systematic literature review and expert consultation. It consists of two parts: sociodemographic data, including sex, age, education level, marital status, monthly household income, and medical payment method; and disease-related data, including pathological type, TNM stage, surgical approach, disease course, comorbidities, and postoperative complications.

Objective nutritional and intake indicators

Nutritional status was not defined solely by blood parameters. BMI, recent weight change recorded in the PG-SGA, daily energy intake, daily protein intake, serum albumin, prealbumin, and hemoglobin were recorded. BMI and weight change were used to describe anthropometric changes; dietary energy and protein intake were used to evaluate whether intake targets were achieved; and albumin, prealbumin, and hemoglobin were analyzed as supportive objective indicators of protein nutritional status and postoperative recovery. These blood parameters were not regarded as stand-alone diagnostic criteria for malnutrition^6,11.

Assessment of dietary intake and target attainment

Individual energy and protein targets were calculated by the clinical dietitian according to body weight, postoperative status, organ function, and feeding tolerance. Energy requirement was generally estimated at 25–30 kcal∙kg^-1∙day^-1, and protein requirement was generally set at 1.2–2.0 g∙kg^-1∙day^-1, with adjustment when clinically indicated6. Dietary intake included oral food, oral nutritional supplements, enteral nutrition, and parenteral nutrition, where applicable. During hospitalization, trained nurses collected daily 24 h food records, including meal type, estimated portion size, oral nutritional supplements, and nutrition formulas. After discharge, patients or caregivers completed 3 day food records before the week 4 follow-up. Food records were converted into kcal and grams of protein using the Chinese Food Composition Tables and nutrition labels for commercial formulas. Protein intake target attainment was defined as the recorded mean daily protein intake meeting the individualized prescribed protein target during the final assessment period.

Intervention protocol for the cohort study

The control group received the routine postoperative nutritional nursing model for EC: routine nutritional risk screening was completed within 24 h after admission using PG-SGA, and patients with a score of ≥4 were referred to a clinical dietitian for consultation and given basic nutritional support recommendations; postoperative dietary management strictly followed routine EC nursing practice, with fasting on postoperative days 1–2, trial water intake on days 3–4, liquid diet on days 5–7, transition to a semiliquid diet at 2 weeks after surgery, and transition to a soft diet at 4 weeks after surgery, together with a standardized dietary guidance manual for patients after EC surgery; nutritional health education was delivered in a group format once weekly for 30 min each time, covering postoperative nutrition knowledge, dietary precautions, and coping strategies for common discomforts; symptom management followed a passive-response model, and the responsible physician was notified for symptomatic treatment only when patients reported complaints such as nausea, pain, or dysphagia; daily food intake was recorded, and nutritional status and symptoms were reassessed 4 weeks after surgery.

Based on the routine treatment and nursing provided to the control group, the intervention group underwent dynamic assessment throughout the study using the NIS-EC scale, and targeted symptom intervention, along with individualized nutritional support plans, was developed and implemented. NIS-EC-guided intervention was implemented according to the dominant high-scoring symptom domain. For digestive tract symptoms, nurses and dietitians adjusted food texture and meal size, provided swallowing and anti-reflux guidance, coordinated antiemetic or analgesic treatment when needed, and escalated oral nutritional supplements or enteral nutrition when intake remained below target. For malaise-related symptoms, the plan included pain assessment, fatigue pacing, sleep guidance, early mobilization within tolerance, and coordination with physicians for symptom medication. For psychological-emotional symptoms, one-to-one education, reassurance, family participation, and referral for psychological support were used when distress interfered with eating. The NIS-EC was reassessed weekly, and the nutritional plan was adjusted according to item-level changes and dietary intake records. The specific implementation process is shown in Figure 1.

Data collection process

Data for the reliability and validity of the scale were collected by two trained investigators. The first assessment was performed within 24 h of admission and included the general information questionnaire, the NIS-EC scale, and the PG-SGA scale; objective nutritional indicators were collected concurrently. Retest assessment was completed 14 ± 2 days after the first assessment. The same investigator administered the NIS-EC again using the same method to evaluate test-retest reliability. All questionnaires were distributed and collected on-site, and completeness was independently checked by two investigators.

Quality control

Before the study began, all investigators underwent 2 days of standardized training. The first day was devoted to theory, including the study protocol, interpretation of scale items, scoring criteria, communication skills for informed consent, and the data collection process. The second day focused on practice and included simulated patient interviews and hands-on scale completion. After training, both a theoretical examination (full score: 100; ≥90 defined as passing) and a practical skills assessment were conducted, and only those who passed both were allowed to participate in the study. During the study period, the research team held weekly meetings to unify assessment standards, address issues arising during data collection, and minimize information bias. After the questionnaires were collected, two researchers independently checked them and marked invalid questionnaires. Invalid questionnaires were defined as those with a missing response rate ≥ 10%, identical item scores, or obvious logical contradictions. Valid data were entered into a spreadsheet database via double data entry, then cross-checked and corrected; outliers were rechecked against the original questionnaires to ensure authenticity and accuracy. The database was stored in encrypted form with graded access permissions to prevent data leakage and tampering.

A blinded assessment was used during outcome evaluation. Researchers responsible for scale assessment, data collection, and data entry did not participate in nursing intervention and were unaware of group allocation throughout the study, thus reducing subjective assessor bias. Objective nutritional indicators were uniformly tested by the hospital laboratory, with internal quality control maintained throughout to ensure test result accuracy and comparability between groups.

Statistical analysis

All data in this study were analyzed using statistical software, and P < 0.05 was considered statistically significant. During data preprocessing, measurement data were first tested for normality using the Shapiro-Wilk test. Measurement data conforming to a normal distribution were expressed as mean ± standard deviation (‾χ ± s), whereas those not conforming to a normal distribution were expressed as median (interquartile range) [M (P25, P75)]. Count data were expressed as frequency and constituent ratio (%). For validation of the scale’s reliability and validity, the critical ratio method and Pearson correlation analysis were used for item analysis and item screening; Cronbach’s α coefficient was used to assess internal consistency, split-half reliability was used for split-half reliability, and the intraclass correlation coefficient (ICC) was used to evaluate test-retest reliability. The content validity index (CVI) was used to assess content validity; exploratory factor analysis to assess structural validity; and Pearson correlation analysis to assess criterion-related validity. Among these, applicability criteria for exploratory factor analysis were KMO > 0.7 and Bartlett’s test of sphericity with P < 0.05; criteria for good reliability were Cronbach’s α > 0.7 and ICC > 0.75; and criteria for good content validity were I-CVI ≥ 0.78 and S-CVI/Ave ≥ 0.9.

For the clinical application study, between-group comparisons were performed using the independent-samples t test or Mann–Whitney U test for continuous variables and the chi-square test or Fisher’s exact test for categorical variables, as appropriate. Within-group comparisons before and after intervention were performed using the paired t test or Wilcoxon signed-rank test. All percentages were rounded to one decimal place. Continuous variables were rounded according to the measurement precision of each variable, and P values were reported to three decimal places except when P < 0.001.

Results

Stage I: Baseline characteristics of the study subjects

Among the 30 participants included in this stage, 22 were male (73.33%) and 8 were female (26.67%). Most were aged 50–69 years, accounting for 21 cases (70.00%); the education level was mainly primary school or below and junior middle school, accounting for 22 cases (73.33%); the pathological type was predominantly squamous cell carcinoma, accounting for 28 cases (93.33%); TNM stage was mainly stage II—III, accounting for...

Discussion

The present study focused on a practical problem in postoperative nutritional management for patients with EC: how to identify symptom barriers to eating and translate that information into individualized nursing care. Using the Theory of Unpleasant Symptoms as the conceptual framework, we developed the NIS-EC and performed a preliminary psychometric evaluation. We then examined its clinical application in an unblinded supportive care study with a non-concurrent historical control comparison. The findings suggest that in...

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Automated Hematology Analyzer	Sysmex Medical Electronics (Shanghai) Co., Ltd.	Model XN-1000	Matched with the designated cyanmethemoglobin method in the original study, used for quantitative detection of hemoglobin concentration in whole blood samples.
Automatic Biochemical Analyzer	Hitachi High-Tech (Shanghai) International Trading Co., Ltd.	Model 7600	The designated detection equipment in the original study, used for quantitative detection of serum biochemical indicators including serum albumin and prealbumin, with in-run quality control maintained throughout the whole process.
Biochemical Assay Combined Calibrator	Beijing ZSBB Co., Ltd.	Lot No. 20240308	Used for system calibration of serum biochemical detection items to ensure the traceability and accuracy of test results.
Biochemical Assay High/Low Level Quality Control Material	Bio-Rad Laboratories (Shanghai) Co., Ltd.	Lot No. 20240315 (Low Level), 20240316 (High Level)	Used for in-run internal quality control throughout the biochemical detection process to ensure the stability of the detection system.
Disposable Vacuum EDTA-K2 Anticoagulant Blood Collection Tube	Jiangsu Yuli Medical Devices Co., Ltd.	5mL	Used for collection and anticoagulation preservation of blood samples for routine blood hemoglobin detection.
Disposable Vacuum Pro-Coagulation Blood Collection Tube	Jiangsu Yuli Medical Devices Co., Ltd.	5mL	Used for collection, pro-coagulation and preservation of blood samples for serum biochemical detection.
Disposable Venous Blood Collection Needle	Shanghai Kindly Medical Devices Co., Ltd.	0.7×25mm	Used for sterile collection of fasting elbow venous blood samples from subjects.
Electronic Height and Weight Measuring Instrument	Changzhou Hengzheng Electronic Instrument Co., Ltd.	Model HGM-300	Used for accurate measurement of subjects' height and body weight in the morning fasting state, for the calculation of body mass index (BMI).
Hematology Assay Quality Control Material	Sysmex Medical Electronics (Shanghai) Co., Ltd.	Lot No. 20240402	Used for internal quality control of hemoglobin detection, in line with the quality control requirements in the original study.
Hemoglobin (Hb) Assay Kit (Cyanmethemoglobin Method)	Sysmex Medical Electronics (Shanghai) Co., Ltd.	Lot No. 20240405	Matched reagent for the designated detection method in the original study, used in conjunction with the automated hematology analyzer.
High-Speed Low-Temperature Centrifuge	Hunan Xiangyi Laboratory Instrument Development Co., Ltd.	Model H1650-W	Used for low-temperature centrifugation and separation of subjects' venous blood samples to obtain serum/plasma test specimens.
IBM SPSS Statistics Software	IBM China Co., Ltd.	Version 26.0	Used for statistical analysis of the full-process data of the study, in line with the designated analysis tool in the original study.
Medical Ultra-Low Temperature Freezer	Haier Biomedical Co., Ltd. (Qingdao)	Model DW-86L388	Used for airtight storage of blood samples and detection reagents at -80 °C to ensure the stability of specimens.
Microsoft Excel Data Processing Software	Microsoft China Co., Ltd.	Version 2021	Used for double-person double-entry, cross-check and preliminary sorting of the study data.
Prealbumin (PA) Assay Kit (Immunoturbidimetric Method)	Roche Diagnostics (Shanghai) Co., Ltd.	Lot No. 20240227	Matched reagent for the designated detection method in the original study, used for quantitative detection of serum prealbumin concentration.
Serum Albumin (ALB) Assay Kit (Bromocresol Green Method)	Beijing ZSBB Co., Ltd.	Lot No. 20240312	Matched reagent for the designated detection method in the original study, used for quantitative detection of serum albumin concentration.