Discussion
The part I of the study found that age did have a bimodal distribution without a significant trimodal distribution. At the same time, the study further confirmed that there are significantly different clinical characteristics of the two types of patients with bimodal distribution, so this study still supports the generally accepted view that RRP patients are divided into JO-RRP or AO-RRP patients according to whether they are over 18 years old.
The recurrence trend in the JO-RRP group was significantly earlier than that in the AO-RRP group, and patients with JO-RRP usually had faster disease growth, were more likely to cause airway obstruction, and relapsed faster after treatment, which was consistent with the characteristics of RRP disease reported in the current literature. Bronchoscopy can directly visualize lesions of the lower respiratory tract while specimens are collected for histopathological examination[26].For all patients with RRP in this study, disease involves the most common site of glottis, followed by supraglottic, consistent with previously reported results[27].
The part II of the study showed that the interval between operations was affected by the age of onset, Derkay score, and surgical method. There are studies found clinical features such as younger age and HPV-11 infection in patients are more dangerous[28].In our study, or JO-RRP, the interval between operations is related to the age of onset, Derkay score, and surgical modality, but not gender. The interval between surgeries increases with age, and the higher the Derkay score, the shorter the spacing between surgeries.
Microdebrider is the most commonly used surgical method, but its surgical interval is the shortest, and the interval between CO2 laser surgery is the longest. Microdebrider have a number of advantages that make them suitable for JO-RRP patients. It can quickly relieve airway obstruction, especially in patients with JO-RRP who have dyspnea due to large lesions. Respiratory papillomatosis involving the trachea is a challenging problem, and the selection of longer Microdebrider allows the cutting of lesions in the trachea [29].
Unlike cold devices, CO2 lasers have a non-contact cutting function and hemostatic effect. A German multicenter study by Papaspyrou[15] on the status of treatment modalities for RRP found that CO2 laser treatment was the most common modality used alone or in combination with other treatment modalities. On the one hand, in the KTP laser surgery protocol, patients can avoid the risks of general anesthesia surgery, while saving a lot of time and energy required for hospitalization, and doctors also save time for general anesthesia waiting and preoperative preparation in local anesthesia surgery.The process is relatively convenient, which is very convenient for patients with repeated attacks to come to the doctor. On the other hand, patients who choose KTP laser surgery usually have mild disease, the lesion volume is not large and the scope is more limited, and the voice function of postoperative patients may recover faster, and patients experience better. For these reasons, KTP lasers are more accessible to patients.
This study has the following limitations. First, changes in voice function and swallowing function were not investigated pre- and post-operatively, as retrospective studies cannot collect complete case information, and studies in this area can be added in future prospective studies. Secondly, we observe whether there is recurrence through laryngoscopy, and formulate a surgical plan according to the patient’s symptoms, but in fact, the time of the two may be somewhat different, and each patient’s medical conditions lead to this time difference. Third, the power of the CO2 laser or KTP laser, or cutting depth may be one of the prognostic factors of this disease, which requires further experimental verification.