Purpose To investigate the pathological characteristics of loco-regional recurrent nasopharyngeal carcinoma ( rNPC ) . Methods Nasopharyngeal biopsy specimens of 46 rNPCs and 63 primary NPCs were collected. HE staining, immunohistochemistry and EBV small RNAs ( EBERs) in-situ hybridization were performed. Results The over-expression rates of both p63 and CK5/6 in rNPC were significantly higher than those of primary NPCs (P=0. 005, P=0. 026), while no statistical significance of Ki-67 over-ex-pression existed between the two groups ( P=0. 387 ) . More necrotic tissues, inflammatory exudates, giant bizarre carcinoma cells, desmoplastic stroma, giant bizarre tumor cells and higher degree of squamous differentiation were found in rNPCs. The carcinoma cells of 5 rNPCs were negative for both EBERs in-situ hybridization and LMP-1 immunohistochemical staining. Conclusion The loco-re-gional rNPC has two peaks of latency interval:2~5 and 9~11 years. The loco-regional rNPC cells have higher degree of squamous differentiation with higher expression of p63 and CK5/6, as well as more invasive ability. In addition, both EBERs in-situ hybridization and LMP-1 immunostaining are negative in 10. 87% (5/46) of loco-regional rNPC.

Objective:To investigate the clinicopathological features, immunophenotype, molecular characteristics, and differential diagnosis of primary intracranial DICER1-mutant sarcoma in order to better understand this tumor type.Methods:A retrospective analysis was conducted on 7 cases of primary intracranial DICER1-mutant sarcoma diagnosed in the Department of Pathology, Sun Yat-sen University Cancer Center, Guangzhou, China between 2021 and 2023 using next-generation sequencing. At the same time, 10 gliosarcomas, 4 intracranial FET::CREB fusion-positive mesenchymal tumors, 4 malignant meningiomas, 3 malignant solitary fibrous tumors, 3 malignant peripheral nerve sheath tumors, 3 synovial sarcomas and 3 rhabdomyosarcomas (total 30 cases) were selected as control.Results:Among the 7 patients with primary intracranial DICER1-mutant sarcoma, 6 were male and 1 was female, aged 10-32 years (median, 23 years). The tissue morphology was predominantly spindle or pleomorphic sarcoma-like, with 6 cases exhibiting eosinophilic globules, and 3 cases showing rhabdomyoblastic or rhabdomyosarcoma-like cell differentiation. Immunohistochemistry revealed focal desmin expression in 3 cases (3/7), ATRX loss in 3 cases (3/7), and p53 mutant pattern in 4 cases (4/7). Additionally, 4 cases (4/7) showed focal or diffuse SALL4 expression, whereas the control cases (30 cases) did not exhibit SALL4 protein expression, suggesting that SALL4 may possess certain auxiliary diagnostic value. Next-generation sequencing confirmed that all 7 cases of primary intracranial DICER1-mutant sarcoma harbored mutations in the DICER1 gene, with 5 cases having the mutation site at p.E1813D. Until May 2024, all 7 patients were alive.Conclusions:Primary intracranial DICER1-mutant sarcoma is a rare tumor. Understanding its morphological characteristics, immunohistochemical and molecular markers and differential diagnosis is crucial to avoid misdiagnosis and to improve diagnostic accuracy of this tumor.

Objective To investigate the prognostic value of American Joint Committee on Cancer-tumor regression grading ( AJCC-TRG) combined with ypTN stage in patients with locally advanced rectal cancer (LARC),who were treated with neoadjuvant chemoradiotherapy,and to identify the subgroups with the worst prognosis. Methods A total of 263 patients with LARC,including 176 males and 87 females,with a median age of 55 years,were admitted to Sun Yat-sen University Cancer Center from 2004 to 2012.All the patients received neoadjuvant chemoradiotherapy before surgery and underwent total mesorectal excision at 6 to 8 weeks after radiotherapy. All the surgical specimens were reevaluated according to the AJCC ( 7th edition)-TRG system and ypTN staging criteria. The prognostic prediction by TRG combined with ypTN was evaluated using survival analysis. The Kaplan-Meier method was used to calculate the rates of overall survival ( OS ) , disease-free survival ( DFS ) , local recurrence-free survival ( LRFS ) , and distant metastasis-free survival ( DMFS ) . The log-rank test was used for survival comparison and univariate prognostic analysis. Results The median follow-up was 601 months. The 5-year rates of OS, DFS, LRFS, and DMFS for all patients were 800%,750%,970%,and 810%,respectively. There were significant differences in OS, DFS,and DMFS between different ypT/TRG subgroups and different ypN/TRG subgroups (all P<005). ypT3-4/TRG 2-3 and ypN1-2/TRG 2-3 subgroups showed the worst prognosis. The 5-year rates of OS,DFS, and DMFS of the two subgroups were 669%/560%, 522%/414%, and 609%/460%, respectively. Conclusions A combination of AJCC-TRG system and ypTN staging can better predict the prognosis of LARC and identify the subgroups with the worst prognosis, which may provide a clinical guidance for postoperative individualized decision on adjuvant therapy for LARC.

Objective:To evaluate the incidence, clinical characteristics and prognosis of second primary malignancies (SPMs) among patients with hypopharyngeal carcinoma (HPC) in real-world analysis.Methods:A total of 594 HPC patients admitted to Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from 2010 to 2018 were retrospectively analyzed.The incidence and clinical characteristics of HPC patients complicated with SPMs were analyzed. Clinical efficacy was compared among different groups.Results:With a median follow-up time of 66.9 months, SPMs were present in 36.4% (216/594) of HPC patients: 22.2% (132/594) were synchronous and 14.1% (84/594) were metachronous. The upper aerodigestive tract was the most common involved region. Compared with patients without SPMs, patients with synchronous and metachronous carcinoma in situ had similar 5-year overall survival (OS) of 42.2% vs. 44.5% ( P=0.958) and 62.2% vs. 44.5% ( P=0.240), respectively. Patients with synchronous invasive SPMs had a worse 5-year OS of 27.2% vs. 44.5% in their counterparts without SPMs ( P=0.001). Patients with metachronous invasive SPMs had similar 5-year OS of 50.2% vs. 44.5% in their counterparts without SPMs ( P=0.587). SPMs accounted for 42.5% of total death in metachronous invasive SPMs group. Conclusions:Patients with HPC have a high probability of developing SPMs. Moreover, the incidence of complicated with esophageal/gastric carcinoma in situ or metachronous SPMs exerts no effect on prognosis, while the occurrence of synchronous SPMs significantly affectes the prognosis of patients. However, the incidence of SPMs is still one of the main death causes in metachronous invasive SPMs group.

Cryoablation therapy with explicit anti-tumor mechanisms and histopathological manifestations has a long history.A large number of clinical practice has shown that cryoablation therapy is safe and effective,making it an ideal tumor treatment method in theory.Previously,its efficacy and clinical application were constrained by the limitations of refrigerants and refrigeration equipment.With the development of the new generation of cryoablation equipment represented by argon helium knives,significant progress has been made in refrigeration efficien-cy,ablation range,and precise temperature measurement,greatly promoting the progression of tumor cryoablation technology.This consensus systematically summarizes the mechanism of cryoablation technology,indications for oral mucosal melanoma(OMM)cryotherapy,clinical treatment process,adverse reactions and management,cryotherapy combination therapy,etc.,aiming to provide reference for carrying out the standardized cryoablation therapy of OMM.

Neck dissection(ND)is one of the main treatment methods for oral and maxillofacial malignancies.Although ND type is in con-stant improvement,but intraoperative peal-pull-push injury of the accessory nerve,muscle,muscle membrane,fascia and ligament induced shoulder syndrome(SS)is still a common postoperative complication,combined with the influence of radiochemotherapy,not only can cause pain,stiffness,numbness,limited dysfunction of shoulder neck and arm,but also may have serious impact on patient's life quality and phys-ical and mental health.At present,there is still a lack of a systematic evaluation and rehabilitation management program for postoperative SS of oral and maxillofacial malignant tumors.Based on the previous clinical practice and the current available evidence,refer to the relevant lit-erature at home and abroad,the experts in the field of maxillofacial tumor surgery and rehabilitation were invited to discuss,modify and reach a consenusus on the etiology,assessment diagnosis,differential diagnosis,rehabilitation strategy and prevention of SS,in order to provide clinical reference.

Surgical operation is the main treatment of oral and maxillofacial tumors.Dysphagia is a common postoperative complication.Swal-lowing disorder can not only lead to mis-aspiration,malnutrition,aspiration pneumonia and other serious consequences,but also may cause psychological problems and social communication barriers,affecting the quality of life of the patients.At present,there is no systematic evalua-tion and rehabilitation management plan for the problem of swallowing disorder after oral and maxillofacial tumor surgery in China.Combining the characteristics of postoperative swallowing disorder in patients with oral and maxillofacial tumors,summarizing the clinical experience of ex-perts in the field of tumor and rehabilitation,reviewing and summarizing relevant literature at home and abroad,and through joint discussion and modification,a group of national experts reached this consensus including the core contents of the screening of swallowing disorders,the phased assessment of prognosis and complications,and the implementation plan of comprehensive management such as nutrition management,respiratory management,swallowing function recovery,psychology and nursing during rehabilitation treatment,in order to improve the evalua-tion and rehabilitation of swallowing disorder after oral and maxillofacial tumor surgery in clinic.

Objective: To investigate the pattern of lymph node metastasis (LNM) in patients with locally advanced (T₃, T₄) laryngeal squamous cell carcinoma (LALSC) and provide reference for the delineation of clinical target volume. Methods: Clinical data of 272 patients with LALSC treated in our hospital from 2000 to 2017 were retrospectively analyzed. All patients underwent bilateral neck dissection (at least level Ⅱ-Ⅳ). The LNM ratio of each node level was calculated. The risk factors of LNM were identified by univariate and multivariate logistic regression analyses. Results: LNM was found in 156 of 272 patients (57.1%). According to the location of primary lesions, all patients were divided into group A (n=72; unilateral without midline involvement), group B (n=86; unilateral with midline involvement) and group C (n=114; giant or central). In group A, the LNM ratio at ipsilateral level Ⅱ, Ⅲ and Ⅳ was 36.3%, 26.4% and 6.9%, whereas 13.9%, 8.3% and 1.4% at the contralateral level, respectively. In group B, the LNM ratio at ipsilateral level Ⅱ, Ⅲ and IV was 1.9%, 29.1% and 11.6%, whereas 18.6%, 14.0% and 1.2% at the contralateral level, respectively. In group C, the LNM ratio at the left neck level Ⅱ, Ⅲ and Ⅳ was 24.6%, 23.7% and 2.6%, whereas 21.9%, 26.3% and 6.1% at the right neck, respectively. Bilateral LNM ratio did not significantly differ between group A and group B/C (15.3%, 25.0%, P=0.093). Ipsilateral level Ⅲ metastasis (OR=2.929, 95%CI 1.041-8.245, P=0.042) and clinical N stage (OR=0.082, 95%CI 0.018-0.373, P=0.001) were associated with contralateral LNM. Ipsilateral level Ⅱ(P=0.043) or Ⅲ(P=0.009) metastasis were risk factors of the ipsilateral level Ⅳ metastasis. Conclusions Neck levels Ⅱ and Ⅲ are the high-risk LNM regions, whereaslevels Ⅳ and V are the low-risk areas. Ipsilateral level Ⅱ or Ⅲ metastases are the risk factors of ipsilateral level Ⅳ and contralateral cervical LNM. Contralateral neck LNM rarely occurs in cN₀ stage patients.