Journals / Journal of Health Sciences and Medicine / 2026 / Volume: 9 Issue: 5

Association of neoadjuvant treatment-initiation season with pathological response and survival in locally advanced rectal cancer

Mustafa Serkan Alemdar(MEDICAL PARK ANTALYA HOSPITAL)0000-0002-7663-6182
Selami Bayram(MEMORIAL ANTALYA HOSPITAL)0000-0002-0930-5025
Pages
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Publication Date
2026-09-19
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⚡ TL;DR(Too Long; Didn't Read)

Pathological complete response (pCR), overall survival (OS), and recurrence-free survival (RFS) were compared, and prognostic factors were assessed by Cox regression.

📌 3 Key Takeaways

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Objective & Hypothesis:Aims: Seasonal variation in sunlight exposure has been linked to cancer prognosis, but whether the season of initiating neoadjuvant treatment affects outcomes in locally advanced rectal cancer is unknown.
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Key Findings & Data:Methods: We retrospectively analysed 156 patients with locally advanced rectal cancer treated with long-course neoadjuvant chemoradiotherapy and total mesorectal excision at two centres (2014-2025).
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Conclusion & Impact:Pathological complete response (pCR), overall survival (OS), and recurrence-free survival (RFS) were compared, and prognostic factors were assessed by Cox regression.
🔬Design:Research Article
📍Scope:2014-2025 Verileri
⚙️Variables:Rectal neoplasms · neoadjuvant therapy · chemoradiotherapy

Abstract

Aims: Seasonal variation in sunlight exposure has been linked to cancer prognosis, but whether the season of initiating neoadjuvant treatment affects outcomes in locally advanced rectal cancer is unknown. We examined its association with pathological response and survival. Methods: We retrospectively analysed 156 patients with locally advanced rectal cancer treated with long-course neoadjuvant chemoradiotherapy and total mesorectal excision at two centres (2014-2025). Patients were grouped by the month of treatment initiation into high-insolation (April-September; n=79) and low-insolation (October-March; n=77) periods. Pathological complete response (pCR), overall survival (OS), and recurrence-free survival (RFS) were compared, and prognostic factors were assessed by Cox regression. Results: The groups were balanced except for older age in the low-insolation group. A pCR occurred in 26 patients (16.7%), without a significant difference between high- and low-insolation groups [13.9%, 95% confidence interval (CI) 6.3-21.6 vs. 19.5%, 95% CI 10.6-28.3; p=0.395]. Over a median follow-up of 55.5 months, season was not associated with OS (5-year 65.9% vs. 58.7%; log-rank p=0.434) or RFS (5-year 56.5% vs. 54.5%; p=0.477); these results were unchanged after multivariable adjustment [OS: hazard ratio (HR) 1.18, p=0.574; RFS: HR 1.22, p=0.443]. Independent predictors were older age and an R1 margin for OS, and older age, lower rectal location, 5-fluorouracil, and lymphovascular invasion for RFS. Conclusion: In this Mediterranean cohort, the season of initiating neoadjuvant chemoradiotherapy was not associated with pathological response or survival; established pathological features remained the principal determinants of outcome. Confirmation in larger, multicentre studies across different latitudes is warranted.

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Cite This Article

Alemdar, M. S., Bayram, S. (2026). Association of neoadjuvant treatment-initiation season with pathological response and survival in locally advanced rectal cancer. Journal of Health Sciences and Medicine, Volume: 9 Issue: 5. https://doi.org/10.32322/jhsm.1991234

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References (24)

  1. Bray F, Laversanne M, Sung H, et al. Global cancer statistics 2022: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries. CA Cancer J Clin. 2024;74(3):229-263. doi:10.3322/caac.21834
  2. Dekker E, Tanis PJ, Vleugels JLA, Kasi PM, Wallace MB. Colorectal cancer. Lancet. 2019;394(10207):1467-1480. doi:10.1016/s0140-6736(19) 32319-0
  3. Sauer R, Becker H, Hohenberger W, et al. Preoperative versus postoperative chemoradiotherapy for rectal cancer. N Engl J Med. 2004; 351(17):1731-1740. doi:10.1056/NEJMoa040694
  4. Bahadoer RR, Dijkstra EA, van Etten B, et al. Short-course radiotherapy followed by chemotherapy before total mesorectal excision (TME) versus preoperative chemoradiotherapy, TME, and optional adjuvant chemotherapy in locally advanced rectal cancer (RAPIDO): a randomised, open-label, phase 3 trial. Lancet Oncol. 2021;22(1):29-42. doi:10.1016/s1470-2045(20)30555-6
  5. Conroy T, Bosset JF, Etienne PL, et al. Neoadjuvant chemotherapy with FOLFIRINOX and preoperative chemoradiotherapy for patients with locally advanced rectal cancer (UNICANCER-PRODIGE 23): a multicentre, randomised, open-label, phase 3 trial. Lancet Oncol. 2021;22(5):702-715. doi:10.1016/s1470-2045(21)00079-6
  6. Maas M, Nelemans PJ, Valentini V, et al. Long-term outcome in patients with a pathological complete response after chemoradiation for rectal cancer: a pooled analysis of individual patient data. Lancet Oncol. 2010; 11(9):835-844. doi:10.1016/s1470-2045(10)70172-8
  7. Hysaj O, Karavasiloglou N, Limam M, Wanner M, Korol D, Rohrmann S. Is season of diagnosis a predictor of cancer survival? Results from the zurich cancer registry. Nutrients. 2022;14(20):4291. doi:10.3390/nu14204291
  8. Porojnicu AC, Robsahm TE, Ree AH, Moan J. Season of diagnosis is a prognostic factor in Hodgkin’s lymphoma: a possible role of sun-induced vitamin D. Br J Cancer. 2005;93(5):571-574. doi:10.1038/sj.bjc.6602722
  9. Moan J, Porojnicu AC, Robsahm TE, et al. Solar radiation, vitamin D and survival rate of colon cancer in Norway. J Photochem Photobiol B. 2005;78(3):189-193. doi:10.1016/j.jphotobiol.2004.11.004
  10. Ertekin C, Yaldız O. Estimation of monthly average daily global radiation on horizontal surface for Antalya (Turkey). Renew Energy. 1999;17(1):95-102. doi:10.1016/S0960-1481(98)00109-8
  11. Kandirmaz HM, Kaba K, Avci M. Estimation of monthly sunshine duration in Turkey using artificial neural networks. Int J Photoenergy. 2014;2014(1):680596. doi:10.1155/2014/680596
  12. Limkin E, Blanchard P, Lacas B, et al. Season of radiotherapy and outcomes of head & neck cancer patients in the MACH-NC & MARCH meta-analyses. Radiother Oncol. 2024;190:110011. doi:10.1016/j.radonc. 2023.110011
  13. Ng K, Nimeiri HS, McCleary NJ, et al. Effect of high-dose vs standard-dose vitamin D3 supplementation on progression-free survival among patients with advanced or metastatic colorectal cancer: the sunshine randomized clinical trial. JAMA. 2019;321(14):1370-1379. doi:10.1001/jama.2019.2402
  14. Urashima M, Ohdaira H, Akutsu T, et al. Effect of vitamin D supplementation on relapse-free survival among patients with digestive tract cancers: the Amaterasu randomized clinical trial. JAMA. 2019; 321(14):1361-1369. doi:10.1001/jama.2019.2210
  15. Vaughan-Shaw PG, Buijs LF, Blackmur JP, et al. The effect of vitamin D supplementation on survival in patients with colorectal cancer: systematic review and meta-analysis of randomised controlled trials. Br J Cancer. 2020;123(11):1705-1712. doi:10.1038/s41416-020-01060-8
  16. Prasanth D, Khan PA, Jamal-E-Fatima, et al. Vitamin D-induced mechanisms in cancer prevention and therapy: recent advances and future opportunities. Animal Model Exp Med. 2025;8(11):1935-1946. doi:10.1002/ame2.70087
  17. Renehan AG, Malcomson L, Emsley R, et al. Watch-and-wait approach versus surgical resection after chemoradiotherapy for patients with rectal cancer (the OnCoRe project): a propensity-score matched cohort analysis. Lancet Oncol. 2016;17(2):174-183. doi:10.1016/s1470-2045(15) 00467-2
  18. Song JH, Yu M, Kang KM, et al. Significance of perineural and lymphovascular invasion in locally advanced rectal cancer treated by preoperative chemoradiotherapy and radical surgery: can perineural invasion be an indication of adjuvant chemotherapy? Radiother Oncol. 2019;133:125-131. doi:10.1016/j.radonc.2019.01.002
  19. Cienfuegos JA, Rotellar F, Baixauli J, et al. Impact of perineural and lymphovascular invasion on oncological outcomes in rectal cancer treated with neoadjuvant chemoradiotherapy and surgery. Ann Surg Oncol. 2015;22(3):916-923. doi:10.1245/s10434-014-4051-5
  20. Nagtegaal ID, Quirke P. What is the role for the circumferential margin in the modern treatment of rectal cancer? J Clin Oncol. 2008;26(2):303-312. doi:10.1200/jco.2007.12.7027
  21. Hofheinz RD, Wenz F, Post S, et al. Chemoradiotherapy with capecitabine versus fluorouracil for locally advanced rectal cancer: a randomised, multicentre, non-inferiority, phase 3 trial. Lancet Oncol. 2012;13(6):579-588. doi:10.1016/S1470-2045(12)70116-X
  22. Loft M, Wong HL, Kosmider S, et al. Real-world outcomes for neoadjuvant capecitabine versus infusional 5-fluorouracil in the treatment of locally advanced rectal cancer. Intern Med J. 2021;51(8):1262-1268. doi:10.1111/imj.15045
  23. Kong JC, Soucisse M, Michael M, et al. Total neoadjuvant therapy in locally advanced rectal cancer: a systematic review and metaanalysis of oncological and operative outcomes. Ann Surg Oncol. 2021;28(12):7476-7486. doi:10.1245/s10434-021-09837-8
  24. Verheij FS, Omer DM, Williams H, et al. Long-term results of organ preservation in patients with rectal adenocarcinoma treated with total neoadjuvant therapy: the randomized phase II OPRA trial. J Clin Oncol. 2024;42(5):500-506. doi:10.1200/jco.23.01208