Salivary gland cancer: ESMO-European Reference Network on Rare Adult Solid Cancers (EURACAN) Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO–EURACAN Clinical Practice Guideline provides key recommendations for managing salivary gland cancer. •The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. •Treatment algorithms for parotid, submandibular, sublingual and minor salivary gland cancer are provided. •The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe. •Recommendations are based on available scientific data and the authors’ collective expert opinion.

B-cell clusters at the invasive margin associate with longer survival in early-stage oral-tongue cancer patients

In oral-cancer, the number of tumor-infiltrating lymphocytes (TILs) associates with improved survival, yet the prognostic value of the cellular composition and localization of TILs is not defined. We quantified densities, localizations, and cellular networks of lymphocyte populations in 138 patients with T1-T2 primary oral-tongue squamous cell carcinoma treated with surgical resections without any perioperative (chemo)radiotherapy, and correlated outcomes to overall survival (OS). Multiplexed in-situ immunofluorescence was performed for DAPI, CD4, CD8, CD20, and pan-cytokeratin using formalin-fixed paraffin-embedded sections, and spatial distributions of lymphocyte populations were assessed in the tumor and stroma compartments at the invasive margin (IM) as well as the center of tumors. We observed a high density of CD4, CD8, and CD20 cells in the stroma compartment at the IM, but neither lymphocyte densities nor networks as single parameters associated with OS. In contrast, assessment of two contextual parameters within the stroma IM region of tumors, i.e., the number of CD20 cells within 20 µm radii of CD20 and CD4 cells, termed the CD20 Cluster Score, yielded a highly significant association with OS (HR 0.38; p = .003). Notably, the CD20 Cluster Score significantly correlated with better OS and disease-free survival in multivariate analysis (HR 0.34 and 0.47; p = .001 and 0.019) as well as with lower local recurrence rate (OR: 0.13; p = .028). Taken together, our study showed that the presence of stromal B-cell clusters at IM, in the co-presence of CD4 T-cells, associates with good prognosis in early oral-tongue cancer patients.

Differences in cancer gene copy number alterations between Epstein-Barr virus-positive and Epstein-Barr virus-negative nasopharyngeal carcinoma

BACKGROUND

Nasopharyngeal carcinoma (NPC) treatment is mainly based on clinical staging. We hypothesize that better understanding of the molecular heterogeneity of NPC can aid in better treatment decisions. Therefore, the purpose of this study was to present our exploration of cancer gene copy-number alterations (CNAs) of Epstein-Barr virus (EBV)-positive and EBV-negative NPC.

METHODS

Multiplex ligation-dependent probe amplification was applied to detect CNAs of 36 cancer genes (n = 103). Correlation between CNAs, clinicopathological features, and survival were examined.

RESULTS

The CNAs occurred significantly more in EBV-negative NPC, with PIK3CA and MCCC1 (P < .001) gain/amplification occurring more frequently. Gain/amplification of cyclin-L1 (CCNL1) and PTK2 (P < .001) predict worse disease-free survival (DFS) in EBV-positive NPC.

CONCLUSION

The EBV-positive and EBV-negative NPC show some similarities in cancer gene CNAs suggesting a common pathogenic route but also important differences possibly indicating divergence in oncogenesis. Copy number gain/amplification of CCNL1 and PTK2 are possibly good predictors of survival in EBV-positive NPC.

Prefabrication of composite tissue for improved tracheal reconstruction

Tracheal repair tissues were evaluated experimentally to provide an evidence-based choice for decision-making in clinical tracheal reconstruction. Tracheal reconstructive tissue was characterized as providing for vascularization, support, and/or lining. A tissue equivalent was developed in the rabbit for each of the individual tissues. The individual tissues consisted of nonepithelialized soft tissue (vascularized fascia), epithelialized tissue (vascularized fascia grafted with buccal mucosa), and supportive tissue (ear cartilage). The 3 reconstructive tissues were evaluated in 30 rabbits after repair of an anterior laryngotracheal defect. Morphometric and histologic analysis was applied to the reconstructions. After a 1-month follow-up period, defects repaired with nonepithelialized soft tissue showed healing by secondary intention and a wound that was contracted to 44% of the initial surface area of the defect. Mucosa-lined soft tissue flaps and cartilage grafts showed a less than 10% wound contraction. Compared to cartilage grafts, mucosalined soft tissue (vascularized fascia grafted with buccal mucosa) seemed preferable for clinical use, because it showed healing by primary intention. A mucosa-lined radial forearm fascia flap was used successfully in cases of restenosis after tracheal resection. One deficiency of the mucosa-lined soft tissue was the absence of supportive tissue. In cases of extensive stenosis, it might be useful to obtain additional expansion of the airway lumen by creating a convexity at the site of reconstruction. In a second set of experiments, we attempted to improve the mucosa-lined soft tissue concept by adding elastic cartilage. A composite tissue consisting of vascularized fascia, buccal mucosa, and auricular cartilage was developed. Heterotopic prefabrication of the composite tissue was essential for survival of the cartilaginous component. Additional airway lumen expansion could be obtained after heterotopic flap prefabrication. After experimental evaluation, the concept of the prefabricated composite tissue was successfully applied in a clinical case of long-segment stenosis. Experimental and clinical evidence suggests that the combination of buccal mucosa and fascia form an optimized tissue combination for tracheal reconstruction. This combination can be improved by adding strips of autologous ear cartilage.

An investigation of airway wound healing using a novel in vivo model

OBJECTIVE

To study the amount of wound contraction and reepithelialization occurring in the healing process of full-thickness mucosal defects treated with and without mitomycin.

STUDY DESIGN

A new wound healing model was developed in which the tracheal mucosa was exteriorized without interference with the blood supply or with the cartilage support of the trachea. This was done by: 1) orthotopic tracheal revascularization in vascularized fascia; 2) isolation of revascularized segment after 14 days; 3) posterior longitudinal incision of revascularized segment; 4) exteriorization of tracheal mucosa with formation of anterior full-thickness mucosal defect; and 5) closure of posterior tracheal incision and reimplantation in the airway. This model was used to study airway wound healing in three groups of animals: 1) controls (revascularization, exteriorization, reimplantation) (N = 6); 2) full-thickness mucosal defect: patch defect (N = 5), circumferential defect (N = 3); and 3) full-thickness mucosal defect after topical mitomycin application: patch defect (N = 7), circumferential defect (N = 3). The animals were followed for periods varying from 2 to 4 weeks or until signs of dyspnea. The surface areas of the wounds before and after follow-up were measured. Wound healing was studied histologically on axial and longitudinal sections.

RESULTS

Group 1: All the animals survived for 1 month. No significant difference existed between surface area of isolated trachea and of reimplanted trachea after follow-up. Group 2: Five animals (patch defects) survived for 1 month. Full-thickness mucosal defects healed by reepithelialization and by a surface area reduction of 58.9% (mean - standard deviation = 10.5). The animals with the circumferential defects showed dyspnea after an average follow-up of 14 days as a result of excessive granulation tissue formation. Group 3: Mitomycin reproducibly inhibited wound closure, yielding wounds that on average closed 56% less than controls by day 14 (P <.001). Histologic comparisons showed that mitomycin blocks angiogenesis during wound healing.

CONCLUSIONS

A wound healing model based on tracheal revascularization, isolation, and reimplantation was developed in rabbits. This model allowed us to study the healing of full-thickness mucosal defects inside the airway.