Metabolic tumour and nodal response to neoadjuvant chemotherapy on FDG PET-CT as a predictor of pathological response and survival in patients with oesophageal adenocarcinoma.

OBJECTIVES: 2-deoxy-2[18F]Fluoro-D-glucose (FDG) PET-CT has an emerging role in assessing response to neoadjuvant therapy in oesophageal cancer. This study evaluated FDG PET-CT in predicting pathological tumour response (pTR), pathological nodal response (pNR) and survival. METHODS: Cohort study of 75 patients with oesophageal or oesophago-gastric junction (GOJ) adenocarcinoma treated with neoadjuvant chemotherapy then surgery at Guy's and St Thomas' NHS Foundation Trust, London (2017-2020). Standardised uptake value (SUV) metrics on pre- and post-treatment FDG PET-CT in the primary tumour (mTR) and loco-regional lymph nodes (mNR) were derived. Optimum SUVmax thresholds for predicting pathological response were identified using receiver operating characteristic analysis. Predictive accuracy was compared to PERCIST (30% SUVmax reduction) and MUNICON (35%) criteria. Survival was assessed using Cox regression. RESULTS: Optimum tumour SUVmax decrease for predicting pTR was 51.2%. A 50% cut-off predicted pTR with 73.5% sensitivity, 69.2% specificity and greater accuracy than PERCIST or MUNICON (area under the curve [AUC] 0.714, PERCIST 0.631, MUNICON 0.659). Using a 30% SUVmax threshold, mNR predicted pNR with high sensitivity but low specificity (AUC 0.749, sensitivity 92.6%, specificity 57.1%, p = 0.010). pTR, mTR, pNR and mNR were independent predictive factors for survival (pTR hazard ratio [HR] 0.10 95% confidence interval [CI] 0.03-0.34; mTR HR 0.17 95% CI 0.06-0.48; pNR HR 0.17 95% CI 0.06-0.54; mNR HR 0.13 95% CI 0.02-0.66). CONCLUSIONS: Metabolic tumour and nodal response predicted pTR and pNR, respectively, in patients with oesophageal or GOJ adenocarcinoma. However, currently utilised response criteria may not be optimal. pTR, mTR, pNR and mNR were independent predictors of survival. KEY POINTS: • FDG PET-CT has an emerging role in evaluating response to neoadjuvant therapy in patients with oesophageal cancer. • Prospective cohort study demonstrated that metabolic response in the primary tumour and lymph nodes was predictive of pathological response in a cohort of patients with adenocarcinoma of the oesophagus or oesophago-gastric junction treated with neoadjuvant chemotherapy followed by surgical resection. • Patients who demonstrated a response to neoadjuvant chemotherapy in the primary tumour or lymph nodes on FDG PET-CT demonstrated better survival and reduced rates of tumour recurrence.

Minimally invasive total adventitial resection of the cardia for tumours of the oesophagogastric junction.

PURPOSE: A cohort study analysing phases and outcomes of the learning curve required to master minimally invasive total adventitial resection of the cardia. METHODS: Data from 198 consecutive oesophagectomies performed by a single surgeon was collected prospectively. Patients' stratification reflected chronologically and technically the four main phases of the learning curve: open surgery (open total adventitial resection of the cardia (TARC), n = 45), hybrid Ivor Lewis oesophagectomy (HILO, n = 50), laparoscopic-thoracoscopic assisted (LTA, n = 56) and totally minimally invasive TARC (TMI TARC, n = 47). Operating time, hospital stay, specimen lymph nodes and resection margins were analysed. Five-year survival was the main long-term outcome measured. RESULTS: Overall 5-year survival was 45%. Perioperative mortality was 1.5% (n = 3). Hospital stay was 22 ± 23 days. Specimen lymph node median was 20 (range: 15-26). Resection margins were negative (R = 0, American College of Pathologists) in 193 cases (97.4%). Five-year survival in the four phases was 37.8%, 44.9%, 42.9% and 55.3%, showing a positive trend towards the end of the learning curve (p = 0.024). Median specimen lymph nodes was 20 (range: 15-22) for open TARC, 18.5 (13-25) for HILO, 19.5 (15-25) for LTA and 23 (18-30) for TMI TARC (p = 0.006). TMI TARC, adenocarcinoma, R >0, T >2, N >0 and LyRa (ratio positive/total specimen nodes) were associated with survival on univariate analysis. T >2 and LyRa independently predicted worse survival on multivariate analysis. CUSUM analysis showed surgical proficiency gain since laparoscopy was introduced. CONCLUSION: Mastering minimally invasive TARC requires a long learning curve. TMI TARC is safe and oncologically appropriate and may benefit long-term survival: it should be validated by randomised trials as a standardised anatomical resection for tumours of the oesophagogastric junction.

Association of dynamic contrast-enhanced MRI and 18F-Fluorodeoxyglucose PET/CT parameters with neoadjuvant therapy response and survival in esophagogastric cancer.

INTRODUCTION: Better predictive markers are needed to deliver individualized care for patients with primary esophagogastric cancer. This exploratory study aimed to assess whether pre-treatment imaging parameters from dynamic contrast-enhanced MRI and 18F-fluorodeoxyglucose (18F-FDG) PET/CT are associated with response to neoadjuvant therapy or outcome. MATERIALS AND METHODS: Following ethical approval and informed consent, prospective participants underwent dynamic contrast-enhanced MRI and 18F-FDG PET/CT prior to neoadjuvant chemotherapy/chemoradiotherapy ± surgery. Vascular dynamic contrast-enhanced MRI and metabolic 18F-FDG PET parameters were compared by tumor characteristics using Mann Whitney U test and with pathological response (Mandard tumor regression grade), recurrence-free and overall survival using logistic regression modelling, adjusting for predefined clinical variables. RESULTS: 39 of 47 recruited participants (30 males; median age 65 years, IQR: 54, 72 years) were included in the final analysis. The tumor vascular-metabolic ratio was higher in patients remaining node positive following neoadjuvant therapy (median tumor peak enhancement/SUVmax ratio: 0.052 vs. 0.023, p = 0.02). In multivariable analysis adjusted for age, gender, pre-treatment tumor and nodal stage, peak enhancement (highest gadolinium concentration value prior to contrast washout) was associated with pathological tumor regression grade. The odds of response decreased by 5% for each 0.01 unit increase (OR 0.95; 95% CI: 0.90, 1.00, p = 0.04). No 18F-FDG PET/CT parameters were predictive of pathological tumor response. No relationships between pre-treatment imaging and survival were identified. CONCLUSION: Pre-treatment esophagogastric tumor vascular and metabolic parameters may provide additional information in assessing response to neoadjuvant therapy.

Pathologic Lymph Node Regression After Neoadjuvant Chemotherapy Predicts Recurrence and Survival in Esophageal Adenocarcinoma: A Multicenter Study in the United Kingdom.

PURPOSE: There is limited evidence regarding the prognostic effects of pathologic lymph node (LN) regression after neoadjuvant chemotherapy for esophageal adenocarcinoma, and a definition of LN response is lacking. This study aimed to evaluate how LN regression influences survival after surgery for esophageal adenocarcinoma. METHODS: Multicenter cohort study of patients with esophageal adenocarcinoma treated with neoadjuvant chemotherapy followed by surgical resection at five high-volume centers in the United Kingdom. LNs retrieved at esophagectomy were examined for chemotherapy response and given a LN regression score (LNRS)-LNRS 1, complete response; 2, <10% residual tumor; 3, 10%-50% residual tumor; 4, >50% residual tumor; and 5, no response. Survival analysis was performed using Cox regression adjusting for confounders including primary tumor regression. The discriminatory ability of different LN response classifications to predict survival was evaluated using Akaike information criterion and Harrell C-index. RESULTS: In total, 17,930 LNs from 763 patients were examined. LN response classified as complete LN response (LNRS 1 ≥1 LN, no residual tumor in any LN; n = 62, 8.1%), partial LN response (LNRS 1-3 ≥1 LN, residual tumor ≥1 LN; n = 155, 20.3%), poor/no LN response (LNRS 4-5; n = 303, 39.7%), or LN negative (no tumor/regression; n = 243, 31.8%) demonstrated superior discriminatory ability. Mortality was reduced in patients with complete LN response (hazard ratio [HR], 0.35; 95% CI, 0.22 to 0.56), partial LN response (HR, 0.72; 95% CI, 0.57 to 0.93) or negative LNs (HR, 0.32; 95% CI, 0.25 to 0.42) compared with those with poor/no LN response. Primary tumor regression and LN regression were discordant in 165 patients (21.9%). CONCLUSION: Pathologic LN regression after neoadjuvant chemotherapy was a strong prognostic factor and provides important information beyond pathologic TNM staging and primary tumor regression grading. LN regression should be included as standard in the pathologic reporting of esophagectomy specimens.

Histopathologic examination and reporting of esophageal carcinomas following preoperative neoadjuvant therapy: practical guidelines and current issues.

Neoadjuvant chemoradiotherapy is being increasingly offered to patients with invasive esophageal carcinoma in an effort to downstage the tumor and consequently increase the rate of curative resection. A substantial amount of data has suggested that pathologic tumor regression following neoadjuvant therapy is an important predictor of local recurrence and long-term survival in esophageal cancer. Therefore, it is important that these posttreatment resection specimens are handled in a standardized manner and a reproducible method of tumor regression grading is used. Pathologic examination of such specimens is not straightforward, and, in fact, it presents a particular challenge to pathologists, especially when a good response to neoadjuvant therapy has been achieved and little or no residual tumor remains. We provide some guidelines for handling and reporting such specimens and outline the commonly used tumor regression grading systems for posttreatment esophagectomy specimens.

Breast cancer metastasis to the stomach may mimic primary gastric cancer: report of two cases and review of literature.

BACKGROUND: The stomach is an infrequent site of breast cancer metastasis. It may prove very difficult to distinguish a breast cancer metastasis to the stomach from a primary gastric cancer on the basis of clinical, endoscopic, radiological and histopathological features. It is important to make this distinction as the basis of treatment for breast cancer metastasis to the stomach is usually with systemic therapies rather than surgery. CASE PRESENTATIONS: The first patient, a 51 year old woman, developed an apparently localised signet-ring gastric adenocarcinoma 3 years after treatment for lobular breast cancer with no clinical evidence of recurrence. Initial gastric biopsies were negative for both oestrogen and progesterone receptors. Histopathology after a D2 total gastrectomy was reported as T4 N3 Mx. Immunohistochemistry for Gross Cystic Disease Fluid Protein was positive, suggesting metastatic breast cancer. The second patient, a 61 year old woman, developed a proximal gastric signet-ring adenocarcinoma 14 years after initial treatment for breast cancer which had subsequently recurred with bony and pleural metastases. In this case, initial gastric biopsies were positive for both oestrogen and progesterone receptors; subsequent investigations revealed widespread metastases and surgery was avoided. CONCLUSION: In patients with a history of breast cancer, a high index of suspicion for potential breast cancer metastasis to the stomach should be maintained when new gastrointestinal symptoms develop or an apparent primary gastric cancer is diagnosed. Complete histopathological and immunohistochemical analysis of the gastric biopsies and comparison with the original breast cancer pathology is important.

Pathological and clinical significance of increased intraepithelial lymphocytes (IELs) in small bowel mucosa.

Intestinal intraepithelial lymphocytes (IELs) belong to a unique T-cell population interspersed between epithelial cells of both the small and large intestine. It is becoming increasingly recognised that an increased number of IELs with a normal villous architecture is within the wide spectrum of histological abnormalities observed in coeliac disease. An increased number of IELs is the earliest pathological change following gluten challenge and a high IEL count may be the only sign of gluten sensitivity. Therefore, the finding of a raised IEL count with normal villous architecture is of sufficient clinical importance to be reported in routine small bowel biopsies. However, it is evident that not all small intestinal biopsy specimens showing increased IELs are explained by gluten sensitivity. Increased IELs in small bowel mucosa have also been associated with autoimmune disorders, tropical sprue, food protein intolerance, Helicobacter pylori-associated gastritis, peptic duodenitis, parasitic and viral infections, as well as the development of intestinal lymphoma. Histological examination of a biopsy specimen of the small bowel remains the diagnostic gold standard for coeliac disease. There will be an ever increasing demand for histological confirmation of gluten sensitivity in patients in whom the classic microscopic appearance of flattened villi may not have fully developed. The more widespread recognition by histopathologists of the pattern of injury manifested by increased numbers of IELs in intestinal biopsy specimens will certainly help in early diagnosis of coeliac disease, lessen diagnostic confusion and influence the modern practice of gastrointestinal tract medicine. This review discusses some of the recent developments in clinical pathology pertaining to increased IELs in small bowel mucosal biopsies.

Esophageal melanocytosis morphologic features and review of the literature.

Endoscopic or macroscopic esophageal melanocytosis is a benign clinicopathologic entity characterized by melanocytic proliferation in esophageal squamous epithelium and melanin deposition in the mucosa. Little is known about the etiology and natural course of this condition, although it has been suggested to be a precursor of primary esophageal melanoma by some authors. Following a search of the bibliographic databases (PubMed and Medline) regarding esophageal melanocytosis and melanosis, thirty-four cases of isolated esophageal melanocytosis (including one unpublished case from us) were found. The histopathologic features of esophageal melanocytosis are reviewed and its differential diagnosis with other pigmented esophageal lesions is discussed.

Atypical forms of microscopic colitis: morphological features and review of the literature.

Microscopic colitis is defined as a syndrome of chronic watery diarrhea with a chronic inflammatory cell infiltrate in the colonic mucosa but without significant abnormalities at colonoscopy. It encompasses at least two histopathologic entities (ie, collagenous and lymphocytic colitis). The recognition and characterization of microscopic colitis has markedly changed the approach to the evaluation and management of chronic diarrhea. The histologic features of collagenous and lymphocytic colitis are well known to most pathologists. By considering the clinical history and symptoms, the pathologist should be able to reach the correct diagnosis in most cases. However, the spectrum of morphologic changes associated with watery diarrhea syndrome appears to be broader than originally thought. Morphologic changes more often associated with chronic inflammatory bowel disease or even chronic ischemic or infectious colitis have been noted in patients with clinically established microscopic colitis. The data presented in this article suggest that microscopic colitis is a heterogeneous entity, which includes both classic and "atypical" forms. Problems arise when cases do not fit the usual pattern or lack some of the findings that are expected. Pathologists should be aware of the presence of atypical forms of microscopic colitis.