Systematic Lymphatic Repair for Reduction of Postoperative Lymphatic Leak Following Neuroblastoma Resection

BACKGROUND

Gross total resection of neuroblastoma is associated with lymphatic leaks that can delay postoperative resumption of treatment. To prevent postoperative lymphatic leak, we introduced systematic lymphatic repair (SLR), which involved oversewing the entire edge of the disrupted lymphatic plane after neuroblastoma resection. We sought to study the impact of SLR on postoperative lymphatic leak and time to return to treatment.

METHODS

We reviewed 60 neuroblastoma patients who underwent gross total resection at KK Women's and Children's Hospital. Patient, disease, and operative factors were correlated with surgical drainage, treatment delay and length of stay (LOS). Among patients with sufficient records, the interaction between variables associated with drainage, delay and LOS outcomes were compared in 14 patients who had SLR versus 35 historical controls who had targeted lymphatic repair (TLR).

RESULTS

Postoperative drain duration and volume were significantly higher in tumors with ≥2 image-derived risk factors (IDRFs, P = 0.005 and P = 0.013, respectively) or vessel encasement (P = 0.031 and P = 0.024, respectively). Longer LOS was significantly associated with ≥2 IDRFs (P = 0.006). All forms of suture repair of lymphatics and use of Tachosil™ were associated with significantly longer postoperative drain duration (P < 0.05); the former was also associated with significantly higher total drain volume (P < 0.05) - indicating appropriate use of these adjuncts in patients at risk of chyle leak. In patients who had suture repair of lymphatics, SLR was significantly associated with reduced postoperative interval to chemotherapy resumption (P = 0.014, two-way ANOVA).

CONCLUSION

A systematic approach to repair of lymphatic channels following neuroblastoma resection can significantly reduce time to postoperative resumption of treatment.

TYPE OF STUDY

Clinical Research.

LEVEL OF EVIDENCE

III.

Clinicopathological and treatment response characteristics of updated rhabdomyosarcoma histomolecular subtypes: An Asian population-based study

AIM

New histomolecular subtypes of rhabdomyosarcoma have recently been defined but their corresponding clinical characteristics are not well described. Also, these clinical phenotypes vary greatly by age and ethnicity but have not been profiled in Asian populations. Thus, we sought to determine the landscape of rhabdomyosarcoma subtypes in a national Asian cohort and compare clinical characteristics among age groups and molecular subtypes.

METHODS

We performed a retrospective population-based study of all rhabdomyosarcoma patients in Singapore public hospitals from 2004 to 2014 (n = 67), and assigned histomolecular subtypes according to the updated 2020 WHO classification of soft tissue tumors following central pathology review and molecular profiling.

RESULTS

Age-specific prevalence followed a tri-modal peak. There were significantly more embryonal and alveolar (p = 0.032) and genitourinary (non-bladder/prostate) tumors (p = 0.033) among children. Older age was associated with complete resection among spindle cell/sclerosing tumors (p = 0.027), with the omission of chemotherapy among embryonal tumors (p = 0.001), and with poorer survival among embryonal and alveolar tumors (p = 0.026, p = 0.022, respectively). Overall survival differed with stage, group, and surgical resection, adjusted for age group (p = 0.004, p = 0.001, p = 0.004, respectively). Spindle-cell/sclerosing tumors showed an indolent phenotype with a significantly lower incidence of nodal metastasis (p = 0.002), but two of 15 patients with MYOD1 mutations had a contrastingly aggressive disease.

CONCLUSION

Disease and treatment response profiles of rhabdomyosarcoma subtypes vary significantly between adults and children, especially surgical resectability. In our Asian population, poorer outcomes were observed in adults with embryonal and alveolar tumors, while activating mutations influence the behavior of otherwise favorable spindle cell/sclerosing tumors.