Effect of neoadjuvant therapy on early postoperative complications in rectal cancer

INTRODUCTION

The treatment of locally advanced rectal cancer is multimodal. It includes neoadjuvant chemoradiotherapy (NCHRT). NCHRT has been shown to reduce the risk of local recurrence. New treatment regimens also have a positive impact on patient survival. NCHRT leads to fibrotic changes in the pelvis and is associated with side effects. NCHRT may have a negative impact on postoperative complications. The aim of this study was to demonstrate whether NCHRT increases the number of early postoperative complications.

METHODS

An analysis of our own cohort of 200 patients with rectal cancer undergoing robotic-assisted surgery between 2018 and 2022 was performed. The cohort was divided into patients who underwent NCHRT and subsequently surgery and patients who underwent primary surgery. The two groups were compared in terms of duration of surgery, blood loss, incidence of anastomotic complications, and quality of mesorectal excision.

RESULTS

Patients who underwent NCHRT had a longer operation time, by 34 minutes on average. We did not demonstrate a higher incidence of anastomotic complications in these patients. Patients who underwent primary surgery had a slightly lower blood loss and better quality of mesorectal excision during surgery. Nevertheless, complete or nearly complete mesorectal anastomosis was achieved in more than 85% of cases in both groups.

CONCLUSION

Radiotherapy results in postradiation changes in the lesser pelvis. These changes impair visibility and dissection during surgery. Operations after NCHRT are more technically demanding and take longer but do not have more anastomotic complications. Also, the quality of mesorectal excision is satisfactory in both groups.

Effect of Laparoscopic Sleeve Gastrectomy on Serum Adipokine Levels

Bariatric procedures are considered to be the most effective treatment options for obesity. One of them is laparoscopic sleeve gastrectomy (LSG), which is nowadays very popular and widely used. LSG leads to weight loss and metabolic improvement and also changes adipokine levels, although it is just a restrictive operation. We describe changes in pro-inflammatory (leptin, resistin, visfatin and chemerin) and anti-inflammatory adipokines (adiponectin, omentin), with adiponectin and leptin being most studied. Their levels are markedly changed after LSG and this may partially explain the weight loss seen after LSG. Adipokines are closely connected to insulin resistance and chronic inflammation both being positively influenced after LSG. Leptin regulates amount of body fat, appetite, thermogenesis and metabolic rate and its levels are positively correlated with both weight and BMI changes after operation. Resistin influences insulin sensitivity, modulates body cholesterol trafficking and its changes after operation correlate with BMI, waist circumference, fat mass, LDL cholesterol and C-reactive protein. Chemerin, an important component of immune system, decreases after bariatric surgery and its levels correlate with BMI, triglyceride levels, and blood glucose. On the other hand, pro-inflammatory adipokine adiponectin, which influences fatty acid oxidation, browning of fat tissue and energy metabolism, is declining after LSG. This decline explains improvement of glucose status after bariatric surgery in patients with diabetes and is correlated with BMI loss, waist circumference and LDL cholesterol level. Effect of LSG goes beyond calory restriction and the changes of adipokines have a great impact on health status of the bariatric patients.

Multiglandular Parathyroid Disease in Primary Hyperparathyroidism With Inconclusive Conventional Imaging

Inconclusive preoperative imaging is a strong predictor of multiglandular parathyroid disease (MGD) in patients with primary hyperparathyroidism (PHPT). MGD was investigated in a cohort of 17 patients with PHPT (mean age 64.9 years, total calcium 2.75 mmol/l and parathyroid hormone (PTH) 113.3 ng/l) who underwent 18F-fluorocholine PET/CT (FCH) imaging before surgery. The initial MIBI SPECT scintigraphy (MIBI) and/or neck ultrasound were not conclusive or did not localize all pathological parathyroid glands, and PHPT persisted after surgery. Sporadic MGD was present in 4 of 17 patients with PHPT (24 %). In 3 of 4 patients with MGD, FCH correctly localized 6 pathological parathyroid glands and surgery was successful. Excised parathyroid glands were smaller (p <0.02) and often hyperplastic in MGD than in single gland disease. In two individuals with MGD, excision of a hyperplastic parathyroid gland led to a false positive decline in intraoperative PTH and/or postoperative serum calcium. Although in one patient it was associated with partial false negativity, parathyroid imaging with FCH seemed to be superior to neck ultrasound and/or MIBI scintigraphy in MGD.

The significance of p16 protein expression in oral squamous cell carcinoma

INTRODUCTION

Human papillomavirus (HPV) infection plays an important role in the etiopathogenesis of oropharyngeal squamous cell carcinomas. HPV detection in these tumours is a positive prognostic marker. The p16 protein expression, which is detected immunohistochemically, is an indirect marker of active HPV infection. Unlike in oropharyngeal carcinoma, in oral carcinoma, the prognostic significance of HPV/p16 positivity is unclear. Some studies even show a worse prognosis in patients with HPV/p16 positive oral carcinoma. The aim of our study is to consider the significance of p16 protein expression in relation to clinicopathological parameters and prognosis in patients with oral squamous cell carcinomas.  Methods: One hundred and twenty patients treated surgically for oral carcinoma were enrolled in the study. The most common anatomical sites of oral carcinoma were the tongue body (54; 45% of cases) and floor of mouth (35; 29.2% of cases). All tumours were analysed immunohistochemically for p16 protein expression. The results were correlated with the clinicopathological parameters and analysed statistically.

RESULTS

Ten patients (8.3%) tested positive for p16 expression. In the study cohort, p16 expression was identified as the most significant factor with a negative effect on survival (p=0.019). Based on the Cox proportional hazard model, the p16-positive patients had four times worse survival than the p16-negative ones. Other factors with a statistically significant effect on survival were T status, N status, and recurrence.

CONCLUSION

The significance of p16 expression differs between oral and oropharyngeal carcinomas. The p16 positivity seems to be a negative prognostic factor in oral carcinomas. Nevertheless, the significance of HPV presence in tumours outside the oropharyngeal area remains unclear.

Mucosal and skin HPV types in tumour-free tonsils and tonsillar tumours

Human papillomavirus (HPV) infection is associated with tonsillar cancer (TC) whose incidence in humans is increasing. Tonsillar tumours are not ordinarily preceded by clinically apparent precancerous lesions, and no markers of the early stage disease are available. Therefore, we evaluated the presence of an active HPV infection also in tumour-free tonsillar tissue. Formalin-fixed paraffin-embedded (FFPE) tonsillar specimens from 114 patients with TC and 114 age and gender matched controls were screened for the presence of HPV DNA, expression of HR-HPV E6 mRNA, and p16 overexpression. HPV DNA was identified in 3.5% of tumour-free tissues, HR-HPV16 and 58 and LR-HPV111 and 17 were each detected in a single sample. No HR HPV E6 mRNA and p16 overexpression was found. The prevalence of HPV DNA in TC was 69.3%, with HPV16 being the most common (94.9%). Eighty-four percent of HPV16-positive tumours expressed HR HPV E6 mRNA, while no E6 mRNA was present in samples positive for HPV52 and 58. The overexpression of p16 correlated well with HPV DNA in TC, but in tumour-free tonsils no overexpression of p16 was detected.Our data provide further evidence of the etiological role of HPV16 in TC. In tumour-free tissue, the presence of HR-HPVs was rare and silent, as shown by direct and indirect markers.

Lymph nodes detection and the mesorectal excision quality evaluation

INTRODUCTION

Detection and examination of proper number of lymph nodes in patients after rectal resection is important for next treatment and management of patients with rectal carcinoma. There are no clear guideliness for minimal count of lymph nodes, variant recommendations agree on the number of 12 (1014) nodes. There are situations, when is not easy to reach this count, mainly in older age groups and in patients after neoadjuvant, especially radiation therapy. As a modality for improvement of lymph nodes harvesting seems to be establishing of defined protocols originally designed for mesorectal excision quality evaluation.

METHODS

The investigation group was formed by patients examined in 2 three-years intervals before and after implementation of the protocol. Elevation in count of harvested lymph nodes was rated generaly and in relation to age groups and gender.

RESULTS

The average count of lymph nodes increased from 10 to 15 nodes, in subset of patients whose received neoadjuvant therapy from 7 to almost 14 nodes. The recommended number of lymph nodes was obtained in all investigated age groups. By the increased number of lymph nodes, rises also possibility of positive nodes found, that can lead to upstaging of the disease, in subset of patients whose received neoadjuvant therapy it is more than 4%.

CONCLUSION

Our conclusions show, that forming of multidisciplinary cooperative groups (chiefly surgeon-pathologist), implementation of defined protocol of surgery, specimen manipulation and investigation by detached specialists lead to benefit consequences for further management and treatment of the patients with colorectal cancer.

Wilms tumor gene 1 (WT1), TP53, RAS/BRAF and KIT aberrations in testicular germ cell tumors

PURPOSE

Wilms tumor gene 1 (WT1), a zinc-finger transcription factor essential for testis development and function, along with other genes, was investigated for their role in the pathogenesis of testicular germ cell tumors (TGCT).

METHODS

In total, 284 TGCT and 100 control samples were investigated, including qPCR for WT1 expression and BRAF mutation, p53 immunohistochemistry detection, and massively parallel amplicon sequencing.

RESULTS

WT1 was significantly (p < 0.0001) under-expressed in TGCT, with an increased ratio of exon 5-lacking isoforms, reaching low levels in chemo-naïve relapsed TGCT patients vs. high levels in chemotherapy-pretreated relapsed patients. BRAF V600E mutation was identified in 1% of patients only. p53 protein was lowly expressed in TGCT metastases compared to the matched primary tumors. Of 9 selected TGCT-linked genes, RAS/BRAF and WT1 mutations were frequent while significant TP53 and KIT variants were not detected (p = 0.0003).

CONCLUSIONS

WT1 has been identified as a novel factor involved in TGCT pathogenesis, with a potential prognostic impact. Distinct biologic nature of the two types of relapses occurring in TGCT has been demonstrated. Differential mutation rate of the key TGCT-related genes has been documented.

[Parametric monitoring of the quality of total mesorectal excision and surgical treatment of rectal carcinoma results of a multicenter study]

INTRODUCTION

Tumour size and the quality of its complete surgical removal are the main prognostic factors in rectal cancer treatment. The number of postoperative local recurrences depends on whether the mesorectum has been completely removed - total mesorectal excision (TME) - and whether tumour-free resection margins have been achieved. The surgery itself and its quality depend on the accuracy of preoperative diagnosis and detection of risk areas in the rectum and mesorectum, on the surgeons skills, and finally on pathological assessment evaluating whether complete tumour excision has been accomplished including circumferential margins of the tumour, and whether mesorectal excision is complete. The aim of our study was to implement and standardize a new method of evaluation of the quality of the surgical procedure - TME - in rectal cancer treatment using an assessment of its circumferential margins (CRO) and completeness of the excision.

METHODS

The study consisted of two parts. The first, multi-centre retrospective phase with 288 patients analysed individual partial parameters of the diagnosis, operations and histological examinations of the rectal cancer. Critical points were identified and a unified follow-up protocol was prepared. In the second, prospective part of this study 600 patients were monitored parametrically focusing on the quality of the TME and its effect on the oncological treatment results.

RESULTS

The proportion of patients with restaging following neoadjuvant therapy increased from 60.0% to 81.7% based on preoperative diagnosis. The number of specimens missing an assessment of the mesorectal excision quality decreased from 52.9% in the retrospective part of to the study to 22.8% in the prospective part. The proportion of actually complete TMEs rose from 22.6% to 26.0%, and that of nearly complete TMEs from 10.1% to 24.0%.

CONCLUSION

The introduction of parametric monitoring into routine clinical practice improved the quality of pre-treatment and preoperative diagnosis, examination of the tissue specimen, and consequently improved quality of the surgical procedure was achieved.

KEY WORDS

rectal cancer TME - parametric monitoring - quality control.