Background/Objectives: In real-world gastric cancer cohorts, incomplete TNM staging and heterogeneous biomarker testing may result from structural characteristics of diagnostic pathways rather than random data loss. This study aimed to evaluate staging completeness and tumour marker availability as pathway-linked phenomena and to examine their associations with metastatic presentation and treatment allocation at diagnosis. Methods: This retrospective observational study included consecutive patients with histologically confirmed gastric carcinoma or adenocarcinoma diagnosed between 2018 and 2021 at a tertiary referral centre. Incomplete staging was defined a priori as the presence of Tx and/or Nx and/or Mx. The primary analytic endpoint was incomplete staging within the subset of patients with defined M status. Secondary analyses evaluated the availability of both CEA and CA19-9. Univariable associations were assessed using Pearson’s χ², and multivariable logistic regression models estimated adjusted odds ratios (ORs) with 95% confidence intervals (CIs). Predefined pathway-oriented endpoints were analysed using multivariable logistic regression models adjusted for key clinical and diagnostic variables. Results: Among 375 patients, incomplete staging occurred frequently and was strongly associated with metastatic disease (M1) and non-surgical management. In multivariable analysis, metastatic presentation remained independently associated with incomplete staging, whereas surgical management and explicit documentation of disease extension were inversely associated. Concurrent availability of CEA and CA19-9 was concentrated within non-surgical and metastatic pathways and was independently associated with documented disease extension. These findings suggest that both staging completeness and tumour marker testing are determined by pathway-specific structures rather than random processes. Conclusions: In real-world gastric cancer care, incomplete TNM staging and tumour marker availability function as measurable features of diagnostic architecture rather than random data limitations. By modelling documentation completeness and testing availability as pathway-dependent phenomena, this study provides a pragmatic framework for improving transparency and interpretability in observational oncology research.

Background/Objectives: Emergency presentation in colorectal cancer (CRC) is commonly regarded as a uniformly high-risk condition, although clinically distinct emergency phenotypes may carry substantially different prognostic implications. We aimed to characterise emergency diagnostic phenotypes, bowel obstruction, perforation, severe stenosis, and lower gastrointestinal bleeding, and to examine their associations with treatment allocation, perioperative mortality, and overall survival after adjustment for recorded covariates. Methods: We performed a retrospective, real-world cohort study of 1051 consecutive patients with CRC diagnosed between 2018 and 2021 at a tertiary referral centre. Patients were assigned to four mutually exclusive groups using a classification defined before outcome analysis (obstructive–perforative, stenotic, haemorrhagic, elective). Overall survival was assessed using Kaplan–Meier analysis and multivariable Cox regression, with formal testing of the proportional hazards assumption. Results: Emergency presentation occurred in 43.7% of patients but was markedly heterogeneous. Metastatic burden did not differ across phenotypes (p = 0.122). The obstructive–perforative phenotype showed the least favourable outcomes: perioperative mortality was 11.5%, and it remained associated with mortality after adjustment for recorded covariates (HR 1.58, 95% CI 1.25–2.00; p < 0.001), with hazard ratios ranging from 1.33 to 1.69 across six model specifications. Haemorrhagic presentation was rectal-predominant and behaved favourably, with survival comparable to elective diagnosis. Among 30-day survivors, the excess hazard was attenuated but persisted (HR 1.39, 95% CI 1.04–1.86). Conclusions: Emergency presentation in CRC is not a monolithic risk category. Recognising the presenting phenotype may offer a pragmatic framework for provisional risk characterisation at diagnosis, but external validation and adjustment for patient-level comorbidity and performance status are required before routine clinical use.

Background/Objectives: Real-world gastric cancer cohorts often show incomplete TNM documentation, which can affect the interpretation of stage, phenotype, and treatment allocation. We aimed to quantify staging completeness, describe advanced-disease phenotype, and examine treatment selection at diagnosis in a real-world gastric cancer cohort. Methods: We performed a retrospective observational study of consecutive patients diagnosed with gastric cancer at a tertiary referral center. Data included age, sex, TNM components, metastatic status, surgery (any vs. none), and available serum markers (CEA, CA19-9). Incomplete staging was defined a priori as Tx and/or Nx and/or Mx. The primary endpoint was metastatic disease at diagnosis (M1) among patients with defined M status. In TNM-complete cases, a composite locally advanced or metastatic endpoint (LAM: M1 or T4 or N2–N3) supported sensitivity analyses. Logistic regression assessed associations with M1 and treatment allocation without biomarker cut-offs (markers modeled as continuous covariates). Results: The cohort included 419 patients. Incomplete staging was observed in 36.8%. M status was defined in 89.5%, with M1 in 52.0% of M-defined cases. Surgery was less frequent in M1 than M0 patients (34.4% vs. 73.3%; p < 0.001). Phenotype stratification showed a marked difference in surgical allocation, which was highest in M0-LAM (89.1%) and lowest in M1 (48.4%). Marker associations were directionally coherent but not definitive. Conclusions: Incomplete staging is common and clinically relevant in real-world gastric cancer and should be reported explicitly. Phenotype-based summaries provide a pragmatic framework for interpreting advanced disease and treatment selection, while tumor markers should be interpreted cautiously without predefined cut-offs.

Background/Objectives: Real-world colorectal cancer (CRC) treatment is documented across multiple routine hospital data domains, which complicates interpretation of treatment-pattern studies. We characterised medication-documented systemic anticancer treatment patterns in CRC and evaluated the consistency of the routine data sources used to ascertain them. Methods: This retrospective observational study included 1310 encounters from 627 patients with C18—C20 diagnosis codes from 1 March to 30 April 2026. Semicolon-delimited medication entries were normalised to named agents. Patient-level medication-derived treatment patterns were characterised among 54 patients with at least one named antineoplastic documented during the fixed study window, without assuming representativeness of the full CRC-coded cohort; oral prescriptions were analysed separately as complementary evidence. Results: Twenty patients (37.0%) had cytotoxic component(s) only, 20 (37.0%) targeted/immune-checkpoint-inhibitor (ICI) plus cytotoxic components, 12 (22.2%) targeted/ICI components without cytotoxic co-documentation, and 2 (3.7%) other antineoplastic agents only. At the first treatment-documented encounter, 24/54 (44.4%) had at least two named antineoplastic agents co-documented. Thirty-three patients (61.1%) had medication-positive treatment documentation in at least two encounters, and 30/33 (90.9%) had the same documented class set across these encounters. Procedure- and medication-based indicators agreed in 890/891 interpretable encounters (99.89%; Cohen’s kappa 0.9953, 95% CI 0.9839–1.0000). Conclusions: Routine hospital medication data showed heterogeneous medication patterns among CRC-coded patients, frequently with multi-component and repeated documentation. Procedure and medication indicators share a hospital workflow; their near-complete concordance describes internal consistency and cannot exclude joint under-capture or establish clinical accuracy or treatment appropriateness.