The role of the bacterial microbiome in the treatment of cancer.

The human microbiome is defined as the microorganisms that reside in or on the human body, such as bacteria, viruses, fungi, and protozoa, and their genomes. The human microbiome participates in the modulation of human metabolism by influencing several intricate pathways. The association between specific bacteria or viruses and the efficacy of cancer treatments and the occurrence of treatment-related toxicity in cancer patients has been reported. However, the understanding of the interaction between the host microbiome and the cancer treatment response is limited, and the microbiome potentially plays a greater role in the treatment of cancer than reported to date. Here, we provide a thorough review of the potential role of the gut and locally resident bacterial microbiota in modulating responses to different cancer therapeutics to demonstrate the association between the gut or locally resident bacterial microbiota and cancer therapy. Probable mechanisms, such as metabolism, the immune response and the translocation of microbiome constituents, are discussed to promote future research into the association between the microbiome and other types of cancer. We conclude that the interaction between the host immune system and the microbiome may be the basis of the role of the microbiome in cancer therapies. Future research on the association between host immunity and the microbiome may improve the efficacy of several cancer treatments and provide insights into the cause of treatment-related side effects.

A novel endoscopic nasopharyngectomy by low-temperature plasma radiofrequency ablation in localized recurrent nasopharyngeal carcinoma.

OBJECTIVE: Endoscopic nasopharyngectomy (ENPG) with en bloc resection has been well accepted in resectable localized recurrent nasopharyngeal carcinoma (rNPC), but it is a difficult technique to master for most otorhinolaryngology head and neck surgeons. Ablation surgery is a new and simplified method to remove tumors. We designed a novel method using low-temperature plasma radiofrequency ablation (LPRA) and evaluated the survival benefit. METHODS: A total of 56 localized rNPC patients were explained in detail and retrospectively analyzed. The surgery method was ablated from the resection margin to the center of the tumor. The postmetastatic overall survival (OS), local relapse-free survival (LRFS) rate, progression-free survival (PFS) and distant metastasis-free survival (DMFS) were analyzed using the Kaplan-Meier method and compared by the log-rank test. RESULTS: All surgeries were successfully performed without any severe postoperative complications or deaths. The median operation time of ablation and harvested NSFF respectively were 29 min (range, 15-100 min) and 101 min (range, 30-180 min). The average number of hospital days postoperation was 3 days (range, 2-5 days). All cases (100.0%) had radical ablation with negative resection margins. The nasopharyngeal defects were completely re-epithelialized in 54 (96.4%) patients. As of the data cutoff (September 3, 2023), the median follow-up time was 44.3 months (range, 17.1-52.7 months, 95% CI: 40.4-48.2). The 3-year OS, LRFS, PFS and DMFS of the entire cohort were 92.9% (95% CI: 0.862-0.996), 89.3% (95% CI: 0.813-0.973), 87.5% (95% CI: 0.789-0.961), and 92.9% (95% CI: 0.862-0.996), respectively. Cycles of radiotherapy were independent risk factors for OS (p = 0.003; HR, 32.041; 95% CI: 3.365-305.064), LRFS (p = 0.002; HR, 10.762; 95% CI: 2.440-47.459), PFS (p = 0.004; HR, 7.457; 95% CI: 1.925-28.877), and DMFS (p = 0.002; HR, 34.776; 95% CI: 3.806-317.799). CONCLUSION: Radical endoscopic nasopharyngectomy by using low-temperature plasma radiofrequency ablation is a novel, safe and simplified method to master and disseminate for treating resectable rNPC. However, further data and longer follow-up time are needed to prove its efficacy.

Endoscopic Nasopharyngectomy Combined With Internal Carotid Artery Pretreatment for Recurrent Nasopharyngeal Carcinoma.

OBJECTIVE: Salvage endoscopic nasopharyngectomy (ENPG) is a reasonable choice for resectable recurrent nasopharyngeal carcinoma (rNPC). However, in past decades, complete removal of the tumor was not feasible when the recurrent lesion was adjacent to the internal carotid artery (ICA). The present article introduces innovative strategies to ensure sufficient surgical margins while avoiding accidental injury to the ICA. STUDY DESIGN: Retrospective study. SETTING: Tertiary care center. METHODS: We retrospectively reviewed rT2-3 rNPC patients with tumor lesions adjacent to the ICA (<5 mm) who underwent ENPG at the Sun Yat-sen University Cancer Center between January 2015 and June 2020. Thirty-seven patients were selected for this study. Seventeen patients underwent ENPG using direct dissection, 10 patients underwent endoscopic-assisted transcervical protection of the parapharyngeal ICA combined with ENPG, and 10 patients underwent ICA embolization followed by ENPG. RESULTS: With a median follow-up duration of 31 months (range, 5 to 53 months), the 2-year overall survival, progression-free survival, locoregional recurrence-free survival, and distant metastasis-free survival rates of salvage ENPG for rNPC adjacent to the ICA were 88.7%, 72.0%, 72.0%, and 97.3%, respectively. The incidences of grade 1-2 and grade 3-5 postoperative complications were 16.2% and 13.5%, respectively. Two patients experienced ICA rupture during direct dissection but were out of danger after vascular embolization therapy. One patient had a positive margin. Two patients had severe nasopharyngeal wound infections with mucosal flap necrosis. CONCLUSION: ENPG combined with ICA pretreatment allows the feasible and effective resection of rNPC lesions adjacent to the ICA.

Adding Concurrent Chemotherapy Significantly Improves the Survival of Stage II-IVb Nasopharyngeal Carcinoma Patients Treated With Concurrent Anti-EGFR Agents.

OBJECTIVE: Anti-EGFR Targeted agents were found to be capable of modulating the antitumor immunity in head and neck cancer and become more and more frequently used in the treatment of nasopharyngeal carcinoma(NPC). We aimed to explore whether adding concurrent chemotherapy influences the survival outcome of patients with stage II-IVb NPC treated with concurrent anti-EGFR agents and intensity-modulated radiation therapy (IMRT) and explore other prognostic factors for the patients. MATERIALS AND METHODS: A total of 656 stage II-IVb NPC patients treated with concurrent anti-EGFR agents plus IMRT between January 2011 and November 2015 were enrolled. Firstly, from these patients, a well-balanced cohort of 302 patients who received concurrent chemotherapy was created by matching potential prognostic factors. Furthermore, for all 656 stage II-IVb NPC patients, univariate and multivariate analyses of overall survival (OS), progression-free survival (PFS), locoregional recurrence-free survival (LRRFS) and distant metastasis-free survival (DMFS) were conducted to identify prognostic factors and to confirm the findings from the matching cohort. RESULTS: Compared with concurrent anti-EGFR agents alone, combining concurrent cisplatin and anti-EGFR agents significantly improved the OS (5-year 94.7% versus 84.3%, P=0.012) and PFS (5-year 82.0% versus 71.7%, P=0.039) of NPC patients with more severe hematologic toxicity and mucositis. The independent prognostic factors identified by multivariate analysis of OS and PFS included concurrent chemotherapy, epstein-barr virus(EBV) status and clinical stage. Patients treated without induction chemotherapy (IC) may achieve more benefits from the addition of concurrent chemotherapy to concurrent anti-EGFR agents. CONCLUSIONS: For stage II-IVb NPC patients treated with concurrent anti-EGFR agents, the addition of concurrent chemotherapy can significantly improve the survival outcome.

Transcervical endoscopic retropharyngeal lymph node (RPLN) dissection in nasopharyngeal carcinoma with RPLN recurrence.

BACKGROUND: Surgical access for retropharyngeal lymph node (RPLN) dissection is difficult. We aimed to examine the efficacy of transcervical endoscopic RPLN dissection (TSE-RPLND) for recurrent RPLN in nasopharyngeal carcinoma (NPC). METHODS: From April 2013 to February 2019, a total of 31 patients with NPC diagnosed with RPLN recurrence underwent TSE-RPLND. The clinical characteristics, complications, and survival outcomes were retrospectively analyzed. RESULTS: The mean duration of surgery, quantity of bleeding and postoperative hospitalization stay were 347.9 minutes, 107.7 mL, and 8.7 days, respectively. After a median follow-up of 31.0 months, the 2-year locoregional relapse-free survival, distant metastasis-free survival, progression-free survival, and overall survival rates were 63.9%, 95.2%, 59.9%, and 83.3%, respectively. The long-term incidences of swallowing problems, permanent nutrient tube, tongue atrophy, and shoulder problems were 6 (19.4%), 3 (9.7%), 3 (9.7%), and 3 (9.7%), respectively. CONCLUSIONS: TSE-RPLND is an effective method to treat RPLN recurrence in NPC, but nerve injury-related complications should not be ignored.

Transoral Robotic Retropharyngeal Lymph Node Dissection in Nasopharyngeal Carcinoma With Retropharyngeal Lymph Node Recurrence.

OBJECTIVES: Nasopharyngeal carcinoma (NPC) patients with retropharyngeal lymph node (RPLN) recurrence typically undergo reirradiation and experience severe radiotoxicity. Salvage open surgery is challenging because gaining access to the retropharyngeal space is complex and risky. Thus, only several centers can perform this procedure, and complications are common. We applied transoral robotic surgery RPLN dissection (TORS-RPLND) to NPC patients with RPLN recurrence to address the problem with open surgery. MATERIALS AND METHODS: From March 2017 to October 2020, 10 NPC patients with RPLN recurrence underwent TORS-RPLND using the da Vinci Si/Xi Surgical System. We applied the balloon occlusion test to protect the internal carotid artery, induction chemotherapy to shrink large tumors preoperatively, and ultrasound positioning to effectively locate unrecognizable RPLNs during surgery. Clinical characteristics, complications, and survival outcome data were retrospectively collected. RESULTS: Of 10 patients, 8 underwent en bloc resection via TORS-RPLND, and the remaining 2 patients were converted to open surgery because we failed to identify the RPLN during TORS. After introducing intraoperative ultrasound positioning, no such failure occurred. The mean operative time and intraoperative blood loss were 297 ± 120 min and 40 ± 43 ml, respectively. All surgical margins were negative. TORS-related complications were mild, and the most severe one was grade 3 dysphagia in one patient who underwent conversion to open surgery (10%). With a median follow-up of 19 months, only 1 (10%) patient developed cervical recurrence. CONCLUSIONS: TORS-RPLND is feasible, safe, and effective in the treatment of NPC patients with RPLN recurrence, especially with the help of intraoperative ultrasound positioning. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E1895-E1902, 2021.