Microbiology of Pelvic Lymphocyst Infection after Lymphadenectomy for Malignant Gynecologic Tumors

Microbiological analysis of infectious lymphocele: Case series and literature review

BACKGROUND

Infectious lymphocele is a rare post-operative complication of abdominal surgery, and few studies have focused on its causative organisms. The aim in this research is to clarify microbiology and appropriate empiric treatment of infective lymphocele.

METHODS

We performed a single center, retrospective observational study between April 2000 and March 2018 with a case review and literature search. Data were collected in a chart review.

RESULTS

Twenty-four cases were founded in our institution. 153 cases, including 16 cases from our institution, that detected causative organisms was also analyzed. Infectious lymphocele was found to occur post gynecological/urological surgery in cancer patients. We also reported that bacteremia incidence and the mortality rate of infectious lymphocele cases were very low. The major sites of infectious lymphocele were pelvis or inguinal area. Our case series and literature review showed Gram positive cocci were the major causative organisms, with Staphylococcus aureus constituting one third of them (53/153 cases). Streptococcus species (26/153cases) and coagulase negative Staphylococci (17/153 cases) were the second and third most detected organisms.

CONCLUSION

In gynecologic and urologic cancer patients, Gram positive cocci were the most common organisms causing lymphocele infection. Gram-positive coverage might be reasonable for empiric therapy in infectious lymphocele.

Profiling of the Causative Bacteria in Infected Lymphocysts after Lymphadenectomy for Gynecologic Cancer by Pyrosequencing the 16S Ribosomal RNA Gene Using Next-Generation Sequencing Technology

Background

Surgery for gynecologic cancer with lymphadenectomy and pelvic radiotherapy can produce lymphoceles that sometimes complicate with infection, resulting in abscesses. The true pathogenic bacteria of abscesses are not always found because of false-negative results due to administered antibiotics and difficulty with detection, including for anaerobic bacteria. Analyzing bacteria flora by next-generation sequencing (NGS) using 16S ribosomal DNA may reveal the true pathogenic bacteria in abscesses. This is the first report on causative pathogens for infectious lymphocele using this technology.

Methods

The subjects were patients who developed infectious lymphocele after surgery for gynecologic cancer at our hospital from July 2015 to September 2016. NGS analyses of bacterial flora were performed using specimens preserved at -80°C. Two steps of PCR were performed for purified DNA samples to obtain sequence libraries. Processing of sequence data, including operational taxonomic unit (OTU) definition, taxonomy assignment, and an OTU BLAST search were performed. All patients gave written informed consent and the study was approved by the institutional research ethics committee.

Results

Six patients underwent puncture and drainage. The result in most cases indicated a single causative pathogen, including Staphylococcus lugdunensis, Streptococcus dysgalactiae, Streptococcus equinus, Enterococcus saccharolyticus, and Escherichia coli. Conclusions. NGS revealed that the causative bacteria in lymphocele infection are normally a single strain, such as a surface Gram-positive coccus or enteric bacteria. Antibiotics should be chosen as appropriate for elimination of these respective bacteria.

Risk factors, microbiology and management of infected lymphocyst after lymphadenectomy for gynecologic malignancies

Objective

To evaluate risk factors, microbiology and management of infected lymphocysts in patients undergoing systemic lymphadenectomy for gynecological cancer.

Methods

Patients with gynecological cancer who developed postoperative lymphocysts after lymphadenectomy were enrolled between January 2009 and June 2017. The clinical data of infected lymphocysts were analyzed and compared with non-infected lymphocysts. Multivariate analysis of risk factors, the microbiology and therapeutic strategies for infected lymphocysts were also evaluated.

Results

A total of 115 patients out of 619 developed postoperative lymphocysts, the incidence of infected lymphocysts was 4.36%. Infected lymphocysts were more frequently found in patients with combined pelvic and para aortic lymphadenectomy, higher number of resected pelvic lymph nodes, lower level of postoperative serum hemoglobin and higher proportion of neutropenia. The median diameter of infected lymphocysts was significantly larger than non-infected (71.89 vs 38.47 mm, P < 0.001) and a large size (diameter over 60 mm) was identified as an independent risk factor for infected lymphocysts (OR = 3.933, P = 0.017). The microbiology of infected lymphocysts includes gram-positive cocci, gram-negative bacillus and anaerobic bacteria. Percutaneous catheter drainage was successfully performed in 20 patients with infected lymphocysts. 16 of 19 patients with large lymphoceles received combined antibiobics and PCD therapy and showed clinical remission in all cases. Patients with large size infected lymphocysts who received combined therapy experienced a significantly shorter treatment period and lower recurrent rate than those with only antibiotics (P = 0.046, P = 0.018).

Conclusions

The current study demonstrated that a diameter over 60 mm was an independent risk factor for infected lymphocysts. The predominant bacteria originated from the urogenital or skin flora. The combination of PCD with appropriate antibiotics was a convenient and effective therapeutic strategy resulting in a high success rate.

Microbiological evaluation of infected pelvic lymphocele after robotic prostatectomy: potential predictors for culture positivity and selection of the best empirical antimicrobial therapy

OBJECTIVES

To examine symptomatology and microbiology of infected lymphocele (LC) post-robotic-assisted radical prostatectomy and pelvic lymph node dissection (PLND) and to assess for potential predictors for LC fluid culture positivity. Secondly, to provide general recommendations about use of select antimicrobial therapy.

METHODS

This was a single-center, IRB-approved, retrospective, case series review conducted between October 2008 and October 2014. Data included symptomatology, microbiology of symptomatic LC in men post-robotic prostatectomy and PLND. Those with infected LC were compared to those men with symptomatic LC in the absence of infection.

RESULTS

Symptomatic LC was seen in 7% of men, and among those, infected LC was seen in 42%. Infected LC cultures showed predominance of G+ cocci such as S. aureus, coagulase-negative Staphylococcus species, S. pyogenes, S. fecalis and S. viridans. Monomicrobial infection was seen in 85%. Multivariate logistic regression showed leukocytosis [Odds: 12.3, p = 0.03, 95% CI (1.2-125)] was significant predictor for culture positivity, whereas trend toward significance for factors such CT findings of thickened walls around the LC +/- air.

CONCLUSIONS

LC infection following PLND for prostate cancer is usually monomicrobial and caused by Gram+ cocci. GI tract and skin flora are the main habitat. High index of suspicion of infected LC is undertaken in the presence of leukocytosis, fever and abnormal CT findings. Based upon our local hospital antibiogram, combination of IV ampicillin/sulbactam and vancomycin is suggested as the best initial empiric therapy in treating these patients.

Can pelvic lymphadenectomy be omitted in patients with stage IA2, IB1, and IIA1 squamous cell cervical cancer?

Purpose

This study aimed to identify the surgical-pathologic risk factors of lymph node metastasis (LNM) in patients with early stage squamous cell cervical cancer and to evaluate the potential efficacy of omitting pelvic lymphadenectomy.

Methods

A total of 276 patients with stage IA2, IB1, and IIA1 squamous cell cervical cancer receiving primary radical hysterectomy with pelvic lymphadenectomy were included in this study.

Results

The incidences of LNM in patients with stage IA2, IB1, and IIA1 squamous cell cervical cancer were 0 % (0/8), 17.4 % (36/207), and 29.5 % (18/61), respectively. The most common location of LNM was the obturator lymph node. Human papilloma virus 16 subtype was the most common infection in early stage squamous cell cervical cancer. Univariate analysis revealed that squamous cell carcinoma antigen (SCCAg) greater than 1.5 μg/L (p < 0.001), tumor size greater than 2 cm (p < 0.001), tumor size greater than 3 cm (p < 0.001), depth of stromal invasion (p < 0.001) and lymphovascular invasion (p < 0.001) were associated with LNM. Logistic regression analysis revealed that depth of stromal invasion {model 1 [p = 0.006; odds ratio (OR) 2.161; 95 % confidence interval (CI) 1.251–3.734], model 2 [p = 0.002; OR 2.344; 95 % CI 1.337–3.989]}, lymphovascular invasion [model 1 (p = 0.004; OR 2.967; 95 % CI 1.411–6.237), model 2 (p = 0.004; OR 2.978; 95 % CI 1.421–6.243)], and SCCAg greater than 1.5 μg/L [model 1 (p = 0.023; OR 2.431; 95 % CI 1.129–5.235), model 2 (p = 0.024; OR 2.418; 95 % CI 1.125–5.194)] were independently associated with LNM.

Conclusions

Pelvic lymphadenectomy may be omitted in patients with SCCAg lower than 1.5 μg/L, superficial stromal invasion and without lymphovascular invasion in stage IA2, IB1, IIA1 squamous cell cervical cancer.

Comparative analyses of postoperative complications and prognosis of different surgical procedures in stage II endometrial carcinoma treatment

OBJECTIVE

To investigate the impact of surgical resection extent on the postoperative complications and the prognosis in patients with stage II endometrial cancer.

METHODS

A total of 54 patients were retrospectively reviewed, 35 patients underwent subradical hysterectomy and 19 patients received radical hysterectomy, both with simultaneous bilateral salpingo-oophorectomy and pelvic and paraaortic lymphadenectomy.

RESULTS

Comparing the surgical outcomes in subradical hysterectomy group vs radical hysterectomy group, there were no significant differences in operative time, estimated blood loss, and hospital stay. After surgery, 37.1% vs 36.8% patients received postoperative radiotherapy in the subradical hysterectomy group vs radical hysterectomy group, without statistically significant difference. As for postoperative complications, the early postoperative complication rate in patients who underwent subradical hysterectomy was 14.3%, significantly lower than that in patients submitted to radical hysterectomy (14.3% vs 42.1%), with P=0.043. However, there was no significant difference in late postoperative complication rate between the two surgical procedures. Regarding the clinical prognosis, patients receiving the subradical hysterectomy showed similar survival to their counterparts undergoing the radical procedures. The relapse rate was 5.71% vs 5.26%, respectively, without significant difference. There were no deaths in both surgical groups.

CONCLUSION

For stage II endometrial carcinoma, subradical hysterectomy presented with less early postoperative complications and similar survival duration and recurrence compared with radical hysterectomy and should be advocated in clinical treatment.