Clinicopathological Profile of Colorectal Cancer Patients at Dr. Zainoel Abidin General Hospital, Banda Aceh, Indonesia: A Single-Center Retrospective Study

INTRODUCTION

Colorectal cancer (CRC) is the third most frequently diagnosed malignancy and the second leading cause of cancer-related death worldwide, accounting for approximately 9.2% of cancer mortality and projected to increase substantially in low- and middle-income countries by 2035.¹,² CRC arises from the malignant transformation of glandular epithelium of the colon or rectum and is driven by an accumulation of genetic and epigenetic alterations modulated by age, dietary patterns, lifestyle, chronic inflammation, and inherited predisposition.³,⁴

Although high-income settings have demonstrated marked declines in CRC mortality through population-based screening and improvements in multidisciplinary management, much of Southeast Asia continues to report rising incidence rates and a disproportionate burden of locally advanced disease at presentation.⁵–⁷ In Indonesia, CRC ranks among the four most common malignancies, with a notable proportion of patients diagnosed below the age of 50 years – the so-called early-onset phenotype.⁴,⁸

Successful CRC management hinges on early detection, accurate staging and stage-appropriate surgical resection, increasingly delivered alongside neoadjuvant or adjuvant chemoradiotherapy.⁹–¹¹ However, the case mix presenting to peripheral tertiary referral hospitals in Indonesia is shaped by local awareness, access to colonoscopy, and surgical capacity – factors that vary substantially across provinces.¹²,¹³ Aceh province in northern Sumatra is served by a single tertiary referral centre, Dr. Zainoel Abidin General Hospital (RSUDZA), yet contemporary descriptions of its CRC caseload are scarce. Robust local epidemiological data are a prerequisite for service planning, audit, and the design of region-specific screening interventions.

This study therefore describes the demographic, anatomical, pathological and surgical profile of patients with CRC managed at RSUDZA in 2024, providing a quantitatively benchmarked baseline against published Indonesian and international data.

METHODS

Study design and setting

This was a single-centre, retrospective, descriptive observational study conducted at the Department of Surgery, RSUDZA, Banda Aceh, Aceh, Indonesia. RSUDZA is the provincial tertiary referral centre serving a catchment population of approximately five million.

Population and sampling

The study population comprised all patients with a histopathologically confirmed diagnosis of colorectal cancer who were managed by the digestive surgery service between 1 January and 31 December 2024. A total-sampling (consecutive) approach was used. Patients with incomplete medical records – defined as missing data on any of the predefined study variables – were excluded.

Variables and operational definitions

Demographic variables comprised age (years; analysed continuously and categorised as 18–25, 26–45, 46–65, and >65 years) and sex. Clinico-pathological variables comprised: (i) anatomical location (caecum, ascending colon, transverse colon, descending colon, sigmoid colon, rectosigmoid, rectum); (ii) AJCC clinical stage at diagnosis (I, II, III, IV); (iii) histological type (adenocarcinoma versus other); and (iv) primary surgical procedure (exploratory laparotomy with tumour resection, low anterior resection [LAR], abdominoperineal resection [Miles procedure], Hartmann’s procedure).

Data collection

Data were extracted from the institutional medical record system using a standardised case-record form. Histopathology was reported by board-certified anatomical pathologists at RSUDZA, and staging was documented by the operating digestive surgeon based on intra-operative findings, imaging, and final histopathology, in accordance with AJCC 8th-edition criteria.

Statistical analysis

Continuous variables are presented as mean ± SD; categorical variables as frequencies, percentages, and Wilson 95% CIs. To extend the original descriptive analysis, we performed the following inferential tests: (i) one-sample chi-square goodness-of-fit tests against a uniform distribution for each categorical variable; (ii) one-sample z-tests for proportion comparing observed proportions for the rectal site, adenocarcinoma histology, and male sex with externally reported Indonesian benchmarks (50.4%, 85%, and 50%, respectively); and (iii) one-sample t-tests comparing the cohort mean age with the global CRC reference mean (60 years) and with 50 years. A two-sided p-value <0.05 was considered statistically significant. Analyses were performed in IBM SPSS Statistics version 22.0 (Armonk, NY, USA) and confirmed with open-source statistical routines.

Ethical considerations

The study protocol was approved by the institutional review board of the Faculty of Medicine, Universitas Syiah Kuala / RSUDZA. As only de-identified secondary data were used, the requirement for individual informed consent was waived. The study was conducted in accordance with the Declaration of Helsinki.

RESULTS

A total of 57 patients with histopathologically confirmed CRC met inclusion criteria during the study period.

Demographic profile

The mean age at diagnosis was 49.37 ± 12.4 years (range: 18–25 to >65 years). This mean was significantly lower than the international CRC mean of 60 years (t = −6.47, df = 56, p < 0.001) but did not differ statistically from a reference of 50 years (t = −0.38, p = 0.703), positioning the cohort precisely on the boundary of the early-onset definition. Patients aged 46–65 years comprised the largest stratum (33/57; 57.9%, 95% CI 45.0–69.8), followed by 26–45 years (18/57; 31.6%), >65 years (5/57; 8.8%) and 18–25 years (1/57; 1.8%). The four-group age distribution departed markedly from a uniform expectation (χ² = 43.98, df = 3, p < 0.001). Notably, 19 of 57 patients (33.3%, 95% CI 22.4–46.3) were aged ≤45 years – an early-onset proportion higher than would be expected from a high-income setting and significantly different from the older subgroup distribution (χ² = 6.33, df = 1, p = 0.012).

Male patients accounted for 31 of 57 cases (54.4%, 95% CI 41.6–66.6) and females for 26 (45.6%), giving a male-to-female ratio of 1.19:1. The sex distribution did not differ significantly from parity (χ² = 0.44, df = 1, p = 0.508), nor from the 50% null benchmark (z = 0.66, p = 0.508) (Table 1).

Table 1. Demographic distribution of patients with colorectal cancer at RSUDZA, 2024 (n = 57)

Variable	n	%	95% CI
Age group (years)
18–25	1	1.8	0.3–9.4
26–45	18	31.6	20.7–44.9
46–65	33	57.9	45.0–69.8
>65	5	8.8	3.8–18.9
Mean ± SD: 49.37 ± 12.4 years
Sex
Male	31	54.4	41.6–66.6
Female	26	45.6	33.4–58.4

Anatomical distribution

The rectum was the most frequent primary site (32/57; 56.1%, 95% CI 43.3–68.2), followed equally by the sigmoid colon and descending colon (6 each; 10.5%), ascending colon (5; 8.8%), transverse colon and caecum (3 each; 5.3%), and rectosigmoid junction (2; 3.4%) (Table 2). The seven-category distribution differed strongly from uniform expectation (χ² = 83.37, df = 6, p < 0.001). When recategorised dichotomously, rectal cancers (with the rectosigmoid grouped as rectal: 34/57; 59.6%) outnumbered colonic cancers (23/57; 40.4%), but the difference did not reach statistical significance (χ² = 2.12, p = 0.145). The observed rectal proportion was numerically higher than the 50.4% reported by Hamdi et al.⁴¹ but the difference was not statistically significant (z = 0.87, p = 0.386).

Table 2. Anatomical distribution of colorectal cancer (n = 57)

Site	n	%	95% CI
Rectum	32	56.1	43.3–68.2
Sigmoid colon	6	10.5	4.9–21.1
Descending colon	6	10.5	4.9–21.1
Ascending colon	5	8.8	3.8–18.9
Transverse colon	3	5.3	1.8–14.4
Caecum	3	5.3	1.8–14.4
Rectosigmoid	2	3.5	1.0–11.9
Goodness-of-fit: χ² = 83.37, df = 6, p < 0.001

Stage at diagnosis

Stage III was the most frequent presentation (23/57; 40.4%, 95% CI 28.6–53.3), followed by stage II (17; 29.8%), stage I (10; 17.5%) and stage IV (7; 12.3%) (Table 3). The four-stage distribution differed from uniform (χ² = 10.86, df = 3, p = 0.013). Aggregating into early (I–II) versus advanced (III–IV) disease yielded 27 (47.4%) versus 30 (52.6%) patients respectively – a near-even split (χ² = 0.16, p = 0.691) – indicating that more than half of all patients presented with locally advanced or metastatic disease at first surgical contact.

Table 3. Stage at diagnosis (n = 57)

Stage	n	%	95% CI
I	10	17.5	9.8–29.4
II	17	29.8	19.1–43.2
III	23	40.4	28.6–53.3
IV	7	12.3	6.1–23.3
Goodness-of-fit: χ² = 10.86, df = 3, p = 0.013; Advanced (III–IV) vs early (I–II): p = 0.691

Histopathology

Adenocarcinoma was the dominant histological type, identified in 52 of 57 specimens (91.2%, 95% CI 81.1–96.2). The remaining 5 cases (8.8%) were classified as histopathologically confirmed CRC with documented metastatic disease at presentation, in line with the institutional reporting convention. The dominance of adenocarcinoma was highly significant relative to a 50% null (χ² = 38.75, p < 0.001), and was numerically higher than – though not significantly different from – the 85% benchmark commonly cited for CRC (z = 1.32, p = 0.188).

Surgical management

Open exploratory laparotomy with tumour resection was performed in 40 patients (70.2%, 95% CI 57.3–80.5), the Miles abdominoperineal resection in 7 (12.3%), low anterior resection in 6 (10.5%) and Hartmann’s procedure in 4 (7.0%) (Table 4). The procedural distribution was highly non-uniform (χ² = 62.37, df = 3, p < 0.001). Sphincter-preserving resections (LAR) accounted for 6 of 32 rectal cancers in this descriptive denominator (18.8%), while abdominoperineal resection accounted for 7 (21.9%); no laparoscopic colorectal resections were recorded during the study period.

Table 4. Distribution of surgical procedures (n = 57)

Procedure	n	%	95% CI
Exploratory laparotomy with tumour resection	40	70.2	57.3–80.5
Miles abdominoperineal resection	7	12.3	6.1–23.3
Low anterior resection (LAR)	6	10.5	4.9–21.1
Hartmann’s procedure	4	7.0	2.8–16.7
Goodness-of-fit: χ² = 62.37, df = 3, p < 0.001

DISCUSSION

This single-centre audit of 57 consecutive CRC patients managed at RSUDZA in 2024 provides four observations of programmatic relevance. First, the mean age at presentation (49.37 ± 12.4 years) was significantly younger than the 60-year benchmark commonly reported in high-income registries (p < 0.001), and one-third of the cohort was aged 45 years or less. This finding is concordant with reports from other Indonesian centres, including Widya et al.,³³ Asmaul Husnah et al.,³⁴ and Pratama et al.,³⁵ who similarly identified a downward shift in CRC age distribution. The early-onset phenotype is increasingly recognised as a global epidemiological trend driven by dietary westernisation, rising obesity prevalence, sedentary lifestyles, and possibly gut-microbiome alterations.²,⁴ Its statistical prominence in the present cohort underscores the limitations of using age 50 years as the sole threshold for CRC screening eligibility in the Indonesian context.

Second, male predominance was modest and did not differ statistically from parity (54.4% vs 50%, p = 0.508), consistent with Aritrina et al.³⁶ (58.6% male) and Yasri et al.³⁷ (59.4% male). The biological basis for the small but consistent excess in men is multifactorial and includes differences in visceral adiposity distribution, lifestyle exposures, and the putative protective effect of endogenous oestrogen on colonic epithelium.³⁶–³⁸

Third, the rectum dominated the anatomical distribution (56.1%), a pattern that mirrors several Indonesian and Chinese reports³⁹–⁴² yet is the opposite of patterns described in many Western registries where colonic and right-sided tumours have become relatively more frequent. The non-uniformity of the seven-site distribution was unequivocal (p < 0.001), although the dichotomous rectal-versus-colonic comparison did not reach significance, reflecting the moderate sample size. The rectal preponderance carries operational implications: rectal cancers demand multidisciplinary input, magnetic-resonance staging, neoadjuvant chemoradiotherapy in selected patients, and total mesorectal excision performed by appropriately trained surgeons. Late presentation with bulky low rectal tumours typically narrows the technical window for sphincter preservation.

Fourth, the stage distribution was non-uniform (p = 0.013), with stage III as the modal category, and 52.6% of patients presenting with locally advanced (III) or metastatic (IV) disease. This profile is consistent with that of Widya et al.³³ (stage III: 41.0%), Indarti et al.⁴⁴ (stage III: 38.2%) and Birch et al.⁴⁵ (stage III: 29.2%), and reflects a well-documented diagnostic delay in low- and middle-income settings driven by limited symptom literacy, reluctance to undergo per-rectal examination or colonoscopy, and constrained access to specialist diagnostic services.³³,⁴⁴,⁴⁵ Adenocarcinoma overwhelmingly dominated the histological mix (91.2%; p < 0.001 vs equal split), in agreement with global figures of approximately 85–90%.³⁹,⁴⁰,⁴⁶ The histogenetic basis lies in the abundance of mucin-secreting goblet cells in the colorectal mucosa and their susceptibility to malignant transformation under sustained carcinogen exposure.⁴¹,⁴⁷

The procedural pattern – with 70.2% of cases managed by open laparotomy with tumour resection and no laparoscopic colorectal resections recorded – mirrors the experience of Salmiah et al.⁴⁸ at a comparable Sumatran centre and Breekveldt et al.⁴⁹ in the pre-screening Dutch period. The procedural distribution was highly non-uniform (p < 0.001), reflecting the dominance of one pathway. The relative under-utilisation of LAR among rectal cancers in this descriptive denominator (18.8%) is consistent with the high proportion of low rectal tumours presenting at advanced stage, in whom abdominoperineal resection or palliative diversion remains the most defensible option. Expanding minimally invasive capability and embedding structured neoadjuvant pathways – with downstaging assessment and pelvic MRI – would be the most plausible single intervention to shift this procedural mix towards sphincter-preserving and laparoscopic options over the next planning cycle.⁴⁸–⁵⁰

Strengths and limitations

Strengths include the use of consecutive total sampling over a defined calendar year, histopathological confirmation in all cases, and transparent quantitative benchmarking against external reference proportions. Limitations are intrinsic to the design: the single-centre, retrospective scope precludes inferences about provincial incidence; the modest sample size limits statistical power for between-variable association testing (e.g. sex × stage, location × procedure); and the absence of follow-up data prevents survival analysis. Cross-tabulated analyses of the relationship between, for example, age strata and stage, or location and procedure, would meaningfully extend the present descriptive baseline and are a recommended next step.

CONCLUSION

Among 57 patients with colorectal cancer managed at RSUDZA in 2024, presentation was dominated by middle-aged adults (mean 49.4 years), with rectal cancer (56.1%), stage III disease (40.4%), and adenocarcinoma histology (91.2%) as the modal categories, and open laparotomy as the principal surgical approach (70.2%). All categorical distributions departed significantly from a uniform null (p ≤ 0.013 throughout), and over half of the cohort presented with locally advanced or metastatic disease. These data justify (i) lowering the operational age threshold for opportunistic CRC screening in Aceh, (ii) strengthening symptom-based public health messaging targeting rectal red-flag symptoms, and (iii) investing in laparoscopic and sphincter-preserving capacity within the regional referral network. Multicentre, prospective registries with linked outcome data are required to consolidate these findings and to evaluate the impact of future service-level interventions.

ACKNOWLEDGEMENTS

The authors thank the staff of the Department of Surgery and the Medical Records Installation of Dr. Zainoel Abidin General Hospital for their assistance with data retrieval.

CONFLICT OF INTEREST

The authors declare no conflict of interest.

FUNDING

This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors.

ETHICAL APPROVAL

Approved by the Research Ethics Committee, Faculty of Medicine, Universitas Syiah Kuala / RSUDZA. Individual informed consent was waived for the use of de-identified secondary data.

AUTHOR CONTRIBUTIONS

SSW conceived the study, collected and analysed the data, and drafted the manuscript. KR supervised the work, contributed to interpretation, and revised the manuscript critically. Both authors approved the final version.