A comprehensive epidemiological investigation of twelve thousand one hundred and thirteen patients diagnosed with invasive lung cancer across Tennessee has identified pronounced sex-specific and demographic disparities in the interval time elapsed between initial diagnosis and definitive surgical intervention. Analyzing historical registry records spanning from 2005 through 2015, researchers determined that male patients, married individuals, residents residing within Appalachian counties, and individuals enrolled in public health insurance plans experienced significantly greater probabilities of undergoing delayed surgical resection. Conversely, advancing age among female patients and Black racial identity were statistically associated with reduced risks of prolonged treatment intervals. Because prompt surgical resection remains a principal curative modality for early-stage and select locoregional pulmonary malignancies, identifying the specific systemic, structural, and demographic variables that correlate with surgical delay provides critical baseline evidence for evaluating surgical care delivery across diverse geographic regions.

Existing clinical literature establishes that extended intervals separating pathological cancer diagnosis from the initiation of definitive treatment may impair curative potential and lead to inferior long-term prognostic outcomes. Although prior systematic reviews of oncological services have reported median treatment initiation intervals ranging broadly from six to forty-five days, significant heterogeneity persists regarding how demographic characteristics interact with administrative and healthcare access boundaries. To establish a standardized benchmark for timely intervention, the researchers defined the interval time to receipt of surgical treatment as the exact duration in weeks between primary histological diagnosis and surgical resection. Using the study cohort median of 3.4 weeks as an empirical clinical threshold, any interval extending beyond 3.4 weeks was categorized as a delayed surgical treatment episode.

The underlying data were derived from the Tennessee Cancer Registry, an administrative repository maintained by the Tennessee Department of Health to document incident neoplasm cases and monitor statewide epidemiological patterns. From an initial identification of thirteen thousand one hundred and eighty-nine lung cancer patients who underwent surgical procedures during the eleven-year study window, investigators applied rigorous inclusion criteria focused specifically on individuals aged eighteen years or older diagnosed with histologically confirmed invasive primary lung cancer classified under specific international diagnostic coding schemes. After excluding one thousand and seventy-six cases characterized by non-invasive lesions, undocumented tumor stages, or missing analytical covariates, the final analytical cohort comprised twelve thousand one hundred and thirteen patients who underwent surgery within fifty-two weeks of diagnosis. The complete study protocol received formal institutional review board approval from the Tennessee Department of Health and was determined to be exempt from human subjects review by federal research protection authorities.

Evaluation of the baseline characteristics within the final study population revealed notable demographic distributions and marked compositional differences across male and female subgroups. Males represented fifty-three percent of the analyzed cohort, while females comprised forty-seven percent. Across both sexes, the predominant proportion of surgically managed patients belonged to the sixty-five to seventy-four age bracket, accounting for 41.6 percent of males and 38.9 percent of females. White patients constituted 90.6 percent of the male cohort and 89.1 percent of the female cohort, whereas Black patients accounted for the primary racial minority subset. Substantial divergences emerged regarding household living structures: 72.4 percent of male patients were married or living under common-law arrangements at the time of diagnosis, compared to only 48.8 percent of female patients. Furthermore, over half of both cohorts resided within designated Appalachian counties, and approximately sixty-nine percent of patients relied upon public health insurance programs, including Medicare and Medicaid.

To rigorously examine variations in surgical timing, the researchers implemented a multifaceted statistical methodology utilizing IBM SPSS Statistics software. Initial evaluations mapped the distribution of the interval time to receipt of surgical treatment, establishing a cohort median of 3.4 weeks, an interquartile range of zero to 6.4 weeks, and an overall standard deviation of 5.0 weeks, with 56.4 percent of all patients experiencing delays beyond the median threshold. Nonparametric Kruskal-Wallis tests were executed to determine whether surgical intervals differed across covariate categories within and between sexes. Subsequently, adjusted multivariable Cox proportional hazards regression models were constructed for the collective cohort and stratified separately by patient sex. Within this modeling framework, adjusted hazard ratios exceeding 1.0 denoted an elevated probability of experiencing surgical delay beyond 3.4 weeks, whereas ratios below 1.0 indicated a decreased likelihood of delay, evaluated at a standard significance threshold of p less than 0.05.

The multivariable regression analyses uncovered a striking contrast in the relationship between patient age and surgical timing between sexes. Among female lung cancer patients, advancing chronological age demonstrated a statistically significant and monotonic protective association against surgical delay. Compared to female patients under the age of forty-five, females in every older age stratum experienced significantly reduced hazards of treatment delay, with adjusted hazard ratios spanning from 0.59 to 0.70 across categories. While prior scientific literature has occasionally linked advancing patient age to overall care delays, the Tennessee findings suggest older women may undergo more prompt surgical resection, aligning with historical patterns wherein older females demonstrated higher likelihoods of receiving resection recommendations.

The analysis of racial demographics revealed that Black patients experienced significantly shorter intervals to surgical intervention than their White counterparts, an outcome that diverged from historical national trends. In the fully adjusted multivariable regression model, Black patients across the overall study cohort exhibited a twenty-one percent lower risk of experiencing surgical delay beyond 3.4 weeks compared to White patients, corresponding to an adjusted hazard ratio of 0.79 with a 95 percent confidence interval of 0.73 to 0.86. This association remained robust in sex-stratified models, with Black males and Black females demonstrating adjusted hazard ratios of 0.81 and 0.76, respectively. The investigators emphasized that this finding must be interpreted with substantial caution, as the analytical cohort was restricted entirely to patients who successfully received surgical intervention. Consequently, the observed cohort may capture a selected subgroup possessing superior healthcare access, while residual confounding from institutional referral patterns, diagnostic pathways, and socioeconomic factors could not be fully measured.

Contrary to widespread oncological literature documenting the protective psychosocial benefits of spousal support, married patients in Tennessee exhibited an elevated risk of surgical delay. In the overall cohort, married individuals were twenty-three percent more likely to encounter surgical delays exceeding 3.4 weeks compared to unmarried peers, yielding an adjusted hazard ratio of 1.23. When disaggregated by sex, married males exhibited a twenty-six percent higher likelihood of delayed surgery, while married females faced a nineteen percent higher risk. Although marriage is frequently associated with enhanced treatment adherence, health navigation assistance, and improved cancer-specific survival, the authors noted that domestic partnerships do not invariably eliminate logistical hurdles. In rural and socioeconomically strained environments, caregiving responsibilities, secondary family obligations, transportation barriers, and complex domestic considerations may inadvertently contribute to longer decision-making or scheduling intervals prior to inpatient surgical admission.

Geographic residency and healthcare payer classifications also exerted significant independent influences on the interval to surgical care. Patients residing within the fifty-two designated Appalachian counties of Tennessee experienced a six percent higher risk of surgical delay compared to residents of the forty-three non-Appalachian counties, reflecting an overall adjusted hazard ratio of 1.06. This geographic disparity aligns with historical observations of diminished healthcare infrastructure, regional poverty, provider shortages, and transportation constraints across the Appalachian region. Concurrently, health insurance status demonstrated a major impact: individuals enrolled in public insurance programs demonstrated approximately thirty percent higher hazards of surgical delay compared to self-pay or uninsured patients. This elevated risk was evident across the total population as well as independently within male and female cohorts, potentially reflecting administrative authorization delays, specialist provider shortages, low institutional reimbursement rates, and medication acquisition barriers within public insurance networks.

The authors outlined several methodological limitations inherent to retrospective registry analyses that must frame the interpretation of these findings. The Tennessee Cancer Registry database lacked granular information regarding patient socioeconomic status, baseline comorbidity scores, and detailed tumor histology, preventing comparisons between small cell and non-small cell lung carcinomas. Furthermore, the dataset could not differentiate whether procedural delays originated from patient-driven scheduling choices, primary care referral bottlenecks, or specialized institutional backlogs, nor did it record neoadjuvant chemotherapy or immunotherapy sequencing. Given the observational design, the documented hazard ratios represent statistical associations rather than direct causal relationships. Nevertheless, the study underscores significant demographic, geographic, and sex-specific variations in surgical timing among invasive lung cancer patients, providing essential baseline data to guide future health services research and structural care improvements.

Subject of Research: Sex-based and demographic disparities in surgical treatment timing for invasive lung cancer

Article Title: Sex-based disparities in interval time to receipt of surgical treatment of invasive lung cancer in Tennessee

Article References: Mamudu, L., Ballew, N., Murguia, A., Tetteh-Bator, E., Masum, M., Dennis, F. J., Whiteside, M., Mamudu, H. M., Sulley, S., Asenso, T. Q., & Atandoh, P. H. (2026). Sex-based disparities in interval time to receipt of surgical treatment of invasive lung cancer in Tennessee. Discover Public Health, 23(1), Article 1701. https://doi.org/10.1186/s12982-026-02756-7

Image Credits: AI Generated

DOI: 10.1186/s12982-026-02756-7

Keywords: invasive lung cancer, surgical treatment delay, Tennessee Cancer Registry, interval time to surgery, sex disparities, Appalachian health, public health insurance, multivariable Cox regression, thoracic oncology, cancer health services, sociodemographic factors, marital status disparities, racial disparities in oncology, surgical timing, healthcare access barriers, observational cancer research