Peripheral lymphovenous communication in lymphoedema

Failure of scintigraphy lymphatic mapping in endometrial cancer. Causes and solutions

AIM

To evaluate the effect of technical problems and patient characteristics on sentinel lymph node (SLN) scintigraphic detection and mapping success in early stages of endometrial cancer (EC).

METHODS

Patients with clinical early stage EC (IA-IB) underwent SLN mapping using technetium-99m-nanocolloid,between September 2011 and February 2020. were included. There were excluded cases with technical problems, 92 patients were included for the analysis of the diagnostic performance and the relation of mapping failure (pelvic unilateral or not detected SLN) with patient (age, body mass index, previous pelvic disease or surgery) and disease characteristics (histology, grade, myometrial invasion, lymphovascular space infiltration, tumor size, and lymphatic infiltration risk).

RESULTS

The overall detection rate was 79%. Lymph node metastases were diagnosed in 7 patients. Age (p=0.01), depth of myometrial invasion ≥ 50% (p=0.04) and high risk of lymphatic infiltration (p=0.02) were positively associated with mapping failure. In multivariate analysis, age was significantly associated with mapping failure [odds ratio=1.63, 95%CI: 1.06-2.50; p=0.027].

CONCLUSIONS

Age, depth of myometrial invasion and high risk of lymphatic infiltration were the factors associated with higher mapping failure. An individualized injection technique, optimizing the methodology, could minimize the detection failures.

Lymphovenous shunts: from development to clinical applications

The lymphatic system is a vast network of vessels that functions to return excess fluid from the interstitial space to the blood stream. Lymphovenous shunts are anastomoses, either natural or surgical, that connect the lymphatic and venous systems. Connections between the thoracic duct and venous system or between the right lymphatic duct and venous system are prime examples of anatomic lymphovenous shunts. Lymphovenous shunts are also present peripherally in tissues such as lymph nodes. Furthermore, pathologic lymphovenous shunts are observed in conditions such as lymphedema, malignancy, and lymphovenous malformations. Surgically, lymphovenous shunts may be constructed as an approach to treat lymphedema. Here, we discuss anatomic and surgical lymphovenous shunts in the context of normal development and disease. This perspective is intended to give an understanding of the role of lymphovenous shunts in health and disease and to show how they can be leveraged to treat disease surgically.

The influence of thoracic duct ligation on long-term survival of patients with esophageal cancer: a propensity score-matched analysis

Background

Ligation of the thoracic duct (LTD) is known to be a useful way to prevent postoperative chylothorax, but its impact on long-term survival is rare to be assessed.

Methods

Data from 609 patients with esophageal cancer who underwent esophagectomy from September, 2012, to January, 2014, were retrospectively collected. The study cohort was classified into two groups: the thoracic duct ligation group (LG) and the non-ligation group (NLG). Propensity score matching (PSM) was performed to control confounding factors between the two groups. Postoperative complications and length of stay were compared between the two groups. Overall survival was estimated using the Kaplan-Meier method, and compared using the log-rank test. Independent prognostic factors were determined using Cox regression analysis.

Results

After PSM, there were 185 patients in each of the two groups. LTD had no significant impact on chylothorax, anastomotic leak, recurrent nerve palsy, pneumonia and length of stay (P>0.05). The 1-, 3- and 5-year survival rates were 87.0%, 64.1%, and 50.9% in the LG, respectively, compared to 85.4%, 59.9%, and 42.3%, respectively, in the NLG. The differences between the 2 groups were not statistically significant (P=0.156). In the multivariable analysis, LTD was not an independent prognostic factor, neither before nor after PSM.

Conclusions

Our study demonstrated that LTD had no significant impact on postoperative complications or long-term survival in patients with esophageal cancer.

Alteration of Blood Circulation in the Upper Limb Before and After Surgery for Breast Cancer Associated with Axillary Lymph Node Dissection or Sentinel Lymph Node Biopsy

BACKGROUND

This aim of this study was to assess and compare arterial and venous circulation in women with axillary lymph node dissection (ALND) and sentinel lymph node biopsy (SLNB) before and after breast cancer surgery.

METHODS AND RESULTS

Fifty-two women took part in the study, divided into three groups: those undergoing ALND at levels I, II, and III (ALNDG), with mean age of 56.29 ± 10.85 years old; those undergoing sentinel lymph node biopsy (SLNBG), with mean age of 57.7 ± 7.07 years old; and controls without diagnosis of breast cancer (CG), with mean age of 53.92 ± 8.85 years old. Maximum venous and arterial flow velocities in upper limbs were assessed before and after surgical treatment for breast cancer by means of Doppler ultrasonography (Nicolet Vascular Versalab SE^®). Data normality was assessed by using the Shapiro-Wilk's test, with normally distributed variables being analyzed with analysis of variance (ANOVA) and post hoc Tukey's test or t-test. For variables with non-normal distribution, Kruskal-Wallis' test and post hoc Dunn's test were used at p < 0.05. There was significant difference in the maximum blood flow velocities, both venous (ALNDG) and arterial (SLNBG).

CONCLUSION

The results suggest that ALND and SLNB can interfere with the upper limp blood circulation.

Sentinel lymph node mapping using SPECT/CT and gamma probe in endometrial cancer: an analysis of parameters affecting detection rate

PURPOSE

SPECT/CT after pericervical injection of technetium-99 m-nanocolloid was shown to be suitable for sentinel lymph node (SLN) mapping in endometrial cancer (EC). The aim of this study was to analyze factors affecting successful SLN detection by means of SPECT/CT such as imaging findings, patient characteristics and tumor biology in a large cohort of patients.

METHODS

One hundred and forty-five consecutive patients suffering from EC who received pre-surgical SLN mapping at our institution between 2011 and 2016 were included in this analysis. SPECT/CT data of abdomen and pelvis (mean 4:20 ± 1:20 h p.i.) were acquired after pericervical injection of technetium-99 m-nanocolloid (mean 230 ± 45 MBq) in all patients. Surgical staging was performed on the day after. Acquisition parameters, patient characteristics, SPECT/CT findings as well as histopathological results were collected.

RESULTS

A total of 282 SLNs were identified by means of SPECT/CT. Overall, preoperative and intraoperative SLN detection rates were 86%, 76% and 74% respectively. The most important factor associated with failure to detect SLNs was the presence of high bone marrow on SPECT/CT (p = 0.005). Peritoneal/abdominal radioactivity was also associated with missed SLN detection in SPECT/CT (p = 0.02). However, the presence of liver/spleen uptake on its own was not predictive for detection failure. Low numbers of detected SLNs in SPECT/CT were slightly related with older age and lower injected activity. No significant influence was found for the parameters of tumor histology and stage, lymph node involvement and the time gap between injection and imaging.

CONCLUSIONS

Venous drainage as indicated by bone marrow uptake is the most important factor associated with scintigraphic SLN detection failure. Moreover, high peritoneal and abdominal activity was also associated with detection failure. Thus, meticulous application of the radiotracer is crucial in EC.

Proposed pathway and mechanism of vascularized lymph node flaps

OBJECTIVE

To investigate the pump mechanism and pathway of lymph transit in vascularized lymph node flaps.

BACKGROUND

Microsurgical treatment of lymphedema with vascularized lymph node transfer can improve signs and symptoms of disease, but the pathways and mechanisms of these flaps warrant further exploration.

METHODS

(Animal model) 72 flaps were raised in 18 rats: 36 groin flaps contained lymph nodes (LN), 36 deep inferior epigastric artery perforator flaps did not (non-LN). Indocyanine green (ICG) was added into normal saline (NS), 1%, 3%, 5%, 7% and 10% albumin. Three rats were assigned to each group. LN and non-LN flaps were submerged in solution and surveyed for venous fluorescence. In the 7% albumin and NS groups, volumetric change of solution was measured. (Human model) A similar experiment was performed in humans using five submental LN flaps.

RESULTS

(Animal model) Fluorescence was detected in the venous pedicle of LN flaps submerged in 5%, 7% and 10% albumin, and half of flaps submerged in 3% albumin. Fluorescence was not detected in LN node flaps submerged in ICG-containing NS or 1% albumin solution. Fluorescence was not detected in non-LN flaps. There was greater volume reduction with LN flaps than non-LN flaps (p<0.001). (Human model) Fluorescence was detected in the venous pedicle of all flaps immersed in lymph.

CONCLUSIONS

ICG fluorescence was detected in the venous pedicle of rat and human LN flaps submerged in lymph or albumin when the concentration was greater than 3%. Based on these results, a pathway for lymphatic uptake is presented.

Estimating Lymphodynamic Conditions and Lymphovenous Anastomosis Efficacy Using (99m)Tc-phytate Lymphoscintigraphy with SPECT-CT in Patients with Lower-limb Lymphedema

Background:

Diagnostic and therapeutic strategies for lower-limb lymphedema have not yet been established. The purpose of this study was to estimate the lymphodynamic condition and therapeutic efficacy of lymphovenous anastomosis (LVA) in lower-limb lymphedema patients using 2-phase ^99mTc-phytate lymphoscintigraphy with single-photon emission computed tomography-computed tomography (SPECT-CT).

Methods:

In this study, consecutive patients with lower-limb lymphedema who underwent 2-phase lymphoscintigraphy using ^99mTc-phytate were enrolled between June 2013 and June 2014. SPECT-CT was also performed to clarify the relationships between functional and morphological information. In both the early and delayed images, inguinal lymph node accumulation, dermal backflow, and their sequential alternations were evaluated, and liver-to-blood ratio and inguinal lymph node-to-blood ratio were calculated. All participants were classified into 6 types of lymphodynamic conditions based on the image findings. Patients with both dermal backflow and associated normal lymphatic vessel accumulation proceeded to LVA and underwent a second lymphoscintigraphy after the operation.

Results:

Of all 30 participants, the largest population was categorized as type 4, which had consistent inguinal lymph node accumulation defect with dermal backflow. In 12 operated cases, dermal backflow was degraded in 10 cases by LVA. Liver-to-blood ratio in both early and delayed images and inguinal lymph node-to-blood ratio in delayed image significantly increased after LVA.

Conclusions:

Lymphoscintigraphy with SPECT-CT can provide both functional and morphological information simultaneously in patients with lower-limb lymphedema. Using these procedures, a type categorization for the patients was devised, which reflects their lymphodynamic conditions. The therapeutic efficacy of LVA could also be estimated quantitatively by the derived findings.