Significant variation in histopathological assessment of endoscopic resections for Barrett's neoplasia suggests need for consensus reporting: propositions for improvement.

Endoscopic resection (ER) is an important diagnostic step in management of patients with early Barrett's esophagus (BE) neoplasia. Based on ER specimens, an accurate histological diagnosis can be made, which guides further treatment. Based on depth of tumor invasion, differentiation grade, lymphovascular invasion, and margin status, the risk of lymph node metastases and local recurrence is judged to be low enough to justify endoscopic management, or high enough to warrant invasive surgical esophagectomy. Adequate assessment of these histological risk factors is therefore of the utmost importance. Aim of this study was to assess pathologist concordance on these histological features on ER specimens and evaluate causes of discrepancy. Of 62 challenging ER cases, one representative H&E slide and matching desmin and endothelial marker were digitalized and independently assessed by 13 dedicated GI pathologists from 8 Dutch BE expert centers, using an online assessment module. For each histological feature, concordance and discordance were calculated. Clinically relevant discordances were observed for all criteria. Grouping depth of invasion categories according to expanded endoscopic treatment criteria (T1a and T1sm1 vs. T1sm2/3), ≥1 pathologist was discrepant in 21% of cases, increasing to 45% when grouping diagnoses according to the traditional T1a versus T1b classification. For differentiation grade, lymphovascular invasion, and margin status, discordances were substantial with 27%, 42%, and 32% of cases having ≥1 discrepant pathologist, respectively. In conclusion, histological assessment of ER specimens of early BE cancer by dedicated GI pathologists shows significant discordances for all relevant histological features. We present propositions to improve definitions of diagnostic criteria.

Avoiding Unnecessary Major Rectal Cancer Surgery by Implementing Structural Restaging and a Watch-and-Wait Strategy After Neoadjuvant Radiochemotherapy.

BACKGROUND: Pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (nCRT) is found in 15-20% of patients with locally advanced rectal cancer. A watch-and-wait (W&W) strategy has been introduced as an alternative strategy to avoid surgery for selected patients with a clinical complete response at multidisciplinary response evaluation. The primary aim of this study was to evaluate the efficacy of the multidisciplinary response evaluation by comparing the proportion of patients with pCR since the introduction of the structural response evaluation with the period before response evaluation. METHODS: This retrospective cohort study enrolled patients with locally advanced rectal cancer who underwent nCRT between January 2009 and May 2018, categorizing them into cohort A (period 2009-2015) and cohort B (period 2015-2018). The patients in cohort B underwent structural multidisciplinary response evaluation with the option of the W&W strategy. Proportion of pCR (ypT0N0), time-to-event (pCR) analysis, and stoma-free survival were evaluated in both cohorts. RESULTS: Of the 259 patients in the study, 21 (18.4%) in cohort A and in 8 (8.7%) in cohort B had pCR (p = 0.043). Time-to-event analysis demonstrated a significant pCR decline in cohort B (p < 0.001). The stoma-free patient rate was 24% higher in cohort B (p < 0.001). CONCLUSION: Multidisciplinary clinical response evaluation after nCRT for locally advanced rectal cancer led to a significant decrease in unnecessary surgery for the patients with a complete response.

[Malignant struma ovarii]. / Maligne struma ovarii.

A 46-year-old patient underwent exploratory laparotomy due to indications of ovarian malignancy. Bilateral salpingooophorectomy, total abdominal hysterectomy, omentectomy and lymphadenectomy were performed, but no residual tumour was seen. Histopathological examination of postoperative specimens revealed malignant struma ovarii, a very rare condition. The patient had a low risk of disease progression (T1>1cmN0M0). Management consisted of initial conservative follow-up, which included administration of thyroid-stimulating hormone (TSH) suppression therapy with levothyroxine.

Sentinel node detection after preoperative short-course radiotherapy in rectal carcinoma is not reliable.

BACKGROUND: Sentinel node (SN) detection may be used in patients with colonic carcinoma. However, its use in patients with rectal carcinoma may be unreliable. To address this, SN detection was evaluated in patients with rectal carcinoma after short-course preoperative radiotherapy. METHODS: Patent Blue V (1-2 ml) was injected peritumorally and submucosally directly after total mesorectal excision (TME) in 34 patients. The first one to four blue lymph nodes were categorized as SNs. All lymph nodes (non-SNs and SNs) were examined by conventional haematoxylin and eosin stained sections. If the SN was negative for metastasis, additional sections were immunostained with anticytokeratin CK7/8. In addition, SN detection was performed in 57 patients with colonic carcinoma. RESULTS: A SN was identified in 26 of 34 patients with rectal carcinoma. In three the SN was the only positive lymph node. There were six false-negative SNs (sensitivity 40 per cent) and two patients were upstaged. By contrast, SN detection was possible in 56 of 57 patient with colonic carcinoma with a sensitivity of 90 per cent, and four patients were upstaged. CONCLUSION: The SN procedure for rectal carcinoma is not reliable in combination with TME and preoperative short-course radiotherapy.

Successful sentinel node identification in colon carcinoma using Patent Blue V.

AIM: The aim of this study was to evaluate the use of Patent Blue V for identification of the sentinel node in patients with colon carcinoma. METHOD: From May 2002, 35 patients operated for colon carcinoma underwent lymphatic mapping using Patent Blue V as marker. Either directly after resection of the colon or during operation 2 ml of Patent Blue V was injected peritumourally, and the first 1 to 4 blue nodes were marked as sentinel nodes. Pathological evaluation was done on a single HE-stained section of all lymph nodes. Only if all sentinel nodes were negative for metastases, serial sectioning and additional immunohistochemical staining against keratine CK 7/8 was performed to reveal micrometastasis in the sentinel nodes. RESULTS: In 33/35 of patients at least one sentinel node was identified. In 10/33 the sentinel node was positive for metastases, and in 5/10 this was the only node containing metastases. One patient had a false negative sentinel node (accuracy 97%, sensitivity 91%). CONCLUSION: Using Patent Blue V, it is possible to identify the sentinel node in most patients with colon cancer. The results are comparable with other sentinel node studies using Lymphazurin.