To explore the prognostic value of chemoradiotherapy based on the depth of invasion (DOI) in patients with oral squamous cell carcinoma.

Patients with oral squamous cell carcinoma who received surgical treatment in a hospital from 2008 to 2016 were enrolled. The chi-square test was used to compare the effects of DOI on postoperative cervical lymph node metastasis and local recurrence. The effects of chemoradiotherapy on postoperative cervical lymph node metastasis, local recurrence, and survival were analyzed based on the DOI.

A total of 111 patients with oral squamous cell carcinoma were included in this study. The postoperative local recurrence rate (P＜0.05) and cervical lymph node metastasis rate (P＜0.05) of patients with 5 mm＜DOI ≤10 mm and DOI＞10 mm were significantly higher than those with DOI ≤5 mm. The time of postoperative recurrence was concentrated within two years after the operation. The greater the DOI was, the shorter the time to postoperative recurrence (P＜0.05). The addition of postoperative chemoradiotherapy did not significantly improve the postoperative local recurrence rate, cervical lymph node metastasis or survival rate of patients with different DOIs (P＞0.05).

DOI has important predictive value for postoperative recurrence, cervical lymph node metastasis and survival rate. However, DOI cannot be used as an independent index to guide whether chemoradiotherapy is needed after oral cancer surgery.

To investigate the distribution patterns and risk factors for multidrug-resistant bacterial pulmonary infections in patients with oral squamous cell carcinoma (OSCC) undergoing flap reconstruction surgery, and to provide evidence for infection prevention and treatment in this population.

This study was approved by the institutional medical ethics committee. We retrospectively analyzed sputum culture results, antimicrobial susceptibility testing data, and clinical records of 109 OSCC patients undergoing flap reconstruction. Chi-square tests were employed to identify pathogens and risk factors for multidrug-resistant bacteria (MDR) in postoperative pulmonary infections. Multivariate logistic regression analysis was conducted to determine MDR risk factors and establish a nomogram prediction model. The model’s discriminatory power, accuracy, and clinical utility were evaluated using receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA).

Among the 109 patients, 52 had negative sputum cultures and 57 tested positive, of whom 14 developed multidrug-resistant (MDR) pulmonary infections. Chi-square analysis revealed that blood transfusion, pre-existing pulmonary diseases, operation time ≥ 490 min, intraoperative blood loss ≥ 400 mL, and abnormal BMI were significant risk factors for postoperative MDR infections (P < 0.05). Multivariate logistic regression identified pre-existing pulmonary diseases, intraoperative blood loss ≥ 400 mL, abnormal BMI, and operative duration ≥ 490 min as independent risk factors for MDR infections (P < 0.05). The nomogram prediction model for MDR infections demonstrated an area under the ROC curve (AUC) of 0.874 (95% CI: 0.775-0.973). The calibration plot showed good agreement between predicted and observed outcomes. DCA indicated a net clinical benefit when the threshold probability for high-risk MDR infections ranged from 0.000 to 0.810. Common MDR pathogens included MDR Pseudomonas aeruginosa, MDR Klebsiella pneumoniae, carbapenem-resistant Acinetobacter baumannii (CRAB), and methicillin-resistant Staphylococcus aureus (MRSA).

Among OSCC patients undergoing flap reconstruction, MDR pulmonary infections were predominantly caused by gram-negative bacteria (including CRAB, MDR Pseudomonas aeruginosa, and MDR Klebsiella pneumoniae along with the gram-positive pathogen MRSA. Pre-existing pulmonary comorbidities, prolonged surgery duration (≥ 490 min), significant intraoperative blood loss (≥ 400 mL), and abnormal BMI were confirmed as independent risk factors for these MDR infections. The nomogram predictive model incorporating these four variables demonstrated clinically reliable accuracy in risk stratification for postoperative MDR pulmonary infections in this patient population.