Endoscopy, in full.

WORKUP (NCCN ESOPH-1): H&P; EGD with biopsy; chest/abdomen CT with oral and IV contrast; pelvis CT with contrast ONLY as clinically indicated; FDG-PET/CT (skull base to mid-thigh) if no evidence of M1 disease; CBC and comprehensive chemistry; EUS if no evidence of M1 or unresectable disease; endoscopic resection (ER) is recommended for accurate staging of early-stage cancers (Tis, T1a, or T1b) and may also be therapeutic; bronchoscopy if the tumor is at or above the carina with no evidence of M1; biopsy of metastatic disease as clinically indicated; assign Siewert category; nutritional assessment and counseling; smoking-cessation counseling; screen for family history. BIOMARKERS: universal MSI (PCR/NGS) or MMR (IHC) testing AND universal PD-L1 testing in ALL newly diagnosed patients; HER2 and CLDN18.2 testing if advanced/metastatic adenocarcinoma is documented or suspected; NGS should be considered. Multidisciplinary evaluation is recommended for stage I-IVA (locoregional) disease (ESOPH-E). ENDOSCOPIC THERAPY (ESOPH-A): the goal of endoscopic therapy (EMR, ESD, and/or ablation) is complete removal or eradication of early-stage disease, pTis, pT1a, and SELECTED superficial pT1b without LVI, plus the pre-neoplastic Barrett's segment. Tis/HGD must first be fully characterized for nodularity, lateral spread and multifocality, with EUS to rule out nodal metastases in select higher-risk cases. Areas of nodularity or ulceration must be RESECTED, not ablated. Completely flat lesions ≤2 cm (squamous HGD/Tis, and BE with flat HGD) should be treated by ER because it gives more accurate histologic assessment; flat lesions >2 cm can be treated by ER but with greater complication risk, and may be treated by ablation alone (data for ablation-alone in squamous HGD are very limited). Lesions pathologically limited to lamina propria/muscularis mucosae (pT1a) or superficial submucosa (pT1b), in the absence of nodal metastases, LVI, or poor differentiation, can be treated with full ER, HOWEVER a thorough patient-and-surgeon discussion of esophagectomy versus the risk of concurrent nodal disease should be undertaken, especially for larger tumors or deeper invasion. Ablation of residual Barrett's should follow ER; complete BE eradication may also be achieved by widefield EMR or ESD at the initial intervention when needed to resect superficial tumor or nodularity ≤2 cm. For SCC, the level of evidence for ablation after ER is LOW; additional ablation may be needed only for multifocal HGD/CIS elsewhere, and may not be needed for completely excised lesions. Endoscopic therapy is 'PREFERRED' for limited early-stage disease: Tis and T1a, ≤2 cm, well or moderately differentiated. Esophagectomy is indicated for extensive carcinoma in situ (pTis/HGD), pT1a, or superficial pT1b, especially nodular disease not adequately controlled endoscopically. PRIMARY TREATMENT, MEDICALLY FIT PATIENTS, ADENOCARCINOMA (ESOPH-13): cT1b-cT2, N0 LOW-RISK (<3 cm, well differentiated) → esophagectomy. cT2 N0 HIGH-RISK (LVI, ≥3 cm, or poorly differentiated), cT1b-cT2 N+, or cT3-cT4a any N → perioperative systemic therapy is PREFERRED (FLOT: 5-FU 2600 mg/m2 IV over 24 h day 1, leucovorin 200 mg/m2, oxaliplatin 85 mg/m2, docetaxel 50 mg/m2, every 14 days, 4 cycles pre- and 4 cycles postoperatively; or FLOT + durvalumab 1500 mg for PD-L1 CPS ≥1 or TAP ≥1%, category 1 for EGJ, category 2A for esophageal adenocarcinoma; note MATTERHORN showed no EFS advantage for durvalumab in diffuse-type disease), QUALIFIER: perioperative therapy is preferred for patients medically fit and with access to frequent toxicity evaluation; preoperative chemoradiation for planned esophagectomy remains an option and may be considered for borderline-resectable patients or patients who are not FLOT candidates (perioperative FOLFOX/CAPOX is another alternative). Consider neoadjuvant or perioperative immune checkpoint inhibitor if the tumor is MSI-H/dMMR (in multidisciplinary consultation; the role of surgery after complete response is unclear). Definitive chemoradiation for patients who are medically unfit/inoperable for surgery or who decline surgery. cT4b → definitive chemoradiation, or chemotherapy alone with invasion of trachea, great vessels, vertebral body, or heart. SQUAMOUS CELL CARCINOMA (ESOPH-2): cT1b-cT2, N0 LOW-RISK (<3 cm, well differentiated) → esophagectomy (non-cervical esophagus). cT2 N0 high-risk (LVI, ≥3 cm, poorly differentiated), cT1b-cT2 N+, or cT3-cT4a any N → PREOPERATIVE CHEMORADIATION is preferred (or definitive chemoradiation). cT4b → definitive chemoradiation, or chemotherapy alone for trachea/great-vessel/vertebral/cardiac invasion. NCCN states explicitly: 'Preoperative chemoradiation is preferred for esophageal SCC.' Preoperative RT dose 41.4-50.4 Gy at 1.8-2.0 Gy/day (23-28 fractions); preferred concurrent regimens include weekly paclitaxel 50 mg/m2 + carboplatin AUC 2 (CROSS, category 1) and fluorouracil + oxaliplatin (category 1). POSTOPERATIVE (ESOPH-F): nivolumab is the preferred postoperative regimen ONLY after PREOPERATIVE CHEMORADIATION with R0 resection and residual pathologic disease (category 1), 240 mg IV every 14 days for 16 weeks, then 480 mg IV every 28 days, maximum treatment duration 1 year. PALLIATION (ESOPH-A/H): esophageal dilation with balloons or bougies for temporary relief of malignant or treatment-related obstruction (avoid overdilation, perforation risk); long-term dysphagia palliation by endoscopic tumor ablation (Nd:YAG laser, PDT, cryoablation) or expandable metal/plastic stents; feeding gastrostomy or jejunostomy for anorexia/dysphagia/malnutrition, but placement of a GASTROSTOMY preoperatively may compromise the gastric vasculature and interfere with gastric-conduit reconstruction and SHOULD BE AVOIDED (feeding jejunostomy is generally preferred for postoperative nutritional support; multidisciplinary expertise is recommended before percutaneous gastrostomy).

WORKUP (NCCN ESOPH-1): H&P; EGD with biopsy; chest/abdomen CT with oral and IV contrast; pelvis CT with contrast ONLY as clinically indicated; FDG-PET/CT (skull base to mid-thigh) if no evidence of M1 disease; CBC and comprehensive chemistry; EUS if no evidence of M1 or unresectable disease; endoscopic resection (ER) is recommended for accurate staging of early-stage cancers (Tis, T1a, or T1b) and may also be therapeutic; bronchoscopy if the tumor is at or above the carina with no evidence of M1; biopsy of metastatic disease as clinically indicated; assign Siewert category; nutritional assessment and counseling; smoking-cessation counseling; screen for family history. BIOMARKERS: universal MSI (PCR/NGS) or MMR (IHC) testing AND universal PD-L1 testing in ALL newly diagnosed patients; HER2 and CLDN18.2 testing if advanced/metastatic adenocarcinoma is documented or suspected; NGS should be considered. Multidisciplinary evaluation is recommended for stage I-IVA (locoregional) disease (ESOPH-E). ENDOSCOPIC THERAPY (ESOPH-A): the goal of endoscopic therapy (EMR, ESD, and/or ablation) is complete removal or eradication of early-stage disease, pTis, pT1a, and SELECTED superficial pT1b without LVI, plus the pre-neoplastic Barrett's segment. Tis/HGD must first be fully characterized for nodularity, lateral spread and multifocality, with EUS to rule out nodal metastases in select higher-risk cases. Areas of nodularity or ulceration must be RESECTED, not ablated. Completely flat lesions ≤2 cm (squamous HGD/Tis, and BE with flat HGD) should be treated by ER because it gives more accurate histologic assessment; flat lesions >2 cm can be treated by ER but with greater complication risk, and may be treated by ablation alone (data for ablation-alone in squamous HGD are very limited). Lesions pathologically limited to lamina propria/muscularis mucosae (pT1a) or superficial submucosa (pT1b), in the absence of nodal metastases, LVI, or poor differentiation, can be treated with full ER, HOWEVER a thorough patient-and-surgeon discussion of esophagectomy versus the risk of concurrent nodal disease should be undertaken, especially for larger tumors or deeper invasion. Ablation of residual Barrett's should follow ER; complete BE eradication may also be achieved by widefield EMR or ESD at the initial intervention when needed to resect superficial tumor or nodularity ≤2 cm. For SCC, the level of evidence for ablation after ER is LOW; additional ablation may be needed only for multifocal HGD/CIS elsewhere, and may not be needed for completely excised lesions. Endoscopic therapy is 'PREFERRED' for limited early-stage disease: Tis and T1a, ≤2 cm, well or moderately differentiated. Esophagectomy is indicated for extensive carcinoma in situ (pTis/HGD), pT1a, or superficial pT1b, especially nodular disease not adequately controlled endoscopically. PRIMARY TREATMENT, MEDICALLY FIT PATIENTS, ADENOCARCINOMA (ESOPH-13): cT1b-cT2, N0 LOW-RISK (<3 cm, well differentiated) → esophagectomy. cT2 N0 HIGH-RISK (LVI, ≥3 cm, or poorly differentiated), cT1b-cT2 N+, or cT3-cT4a any N → perioperative systemic therapy is PREFERRED (FLOT: 5-FU 2600 mg/m2 IV over 24 h day 1, leucovorin 200 mg/m2, oxaliplatin 85 mg/m2, docetaxel 50 mg/m2, every 14 days, 4 cycles pre- and 4 cycles postoperatively; or FLOT + durvalumab 1500 mg for PD-L1 CPS ≥1 or TAP ≥1%, category 1 for EGJ, category 2A for esophageal adenocarcinoma; note MATTERHORN showed no EFS advantage for durvalumab in diffuse-type disease), QUALIFIER: perioperative therapy is preferred for patients medically fit and with access to frequent toxicity evaluation; preoperative chemoradiation for planned esophagectomy remains an option and may be considered for borderline-resectable patients or patients who are not FLOT candidates (perioperative FOLFOX/CAPOX is another alternative). Consider neoadjuvant or perioperative immune checkpoint inhibitor if the tumor is MSI-H/dMMR (in multidisciplinary consultation; the role of surgery after complete response is unclear). Definitive chemoradiation for patients who are medically unfit/inoperable for surgery or who decline surgery. cT4b → definitive chemoradiation, or chemotherapy alone with invasion of trachea, great vessels, vertebral body, or heart. SQUAMOUS CELL CARCINOMA (ESOPH-2): cT1b-cT2, N0 LOW-RISK (<3 cm, well differentiated) → esophagectomy (non-cervical esophagus). cT2 N0 high-risk (LVI, ≥3 cm, poorly differentiated), cT1b-cT2 N+, or cT3-cT4a any N → PREOPERATIVE CHEMORADIATION is preferred (or definitive chemoradiation). cT4b → definitive chemoradiation, or chemotherapy alone for trachea/great-vessel/vertebral/cardiac invasion. NCCN states explicitly: 'Preoperative chemoradiation is preferred for esophageal SCC.' Preoperative RT dose 41.4-50.4 Gy at 1.8-2.0 Gy/day (23-28 fractions); preferred concurrent regimens include weekly paclitaxel 50 mg/m2 + carboplatin AUC 2 (CROSS, category 1) and fluorouracil + oxaliplatin (category 1). POSTOPERATIVE (ESOPH-F): nivolumab is the preferred postoperative regimen ONLY after PREOPERATIVE CHEMORADIATION with R0 resection and residual pathologic disease (category 1), 240 mg IV every 14 days for 16 weeks, then 480 mg IV every 28 days, maximum treatment duration 1 year. PALLIATION (ESOPH-A/H): esophageal dilation with balloons or bougies for temporary relief of malignant or treatment-related obstruction (avoid overdilation, perforation risk); long-term dysphagia palliation by endoscopic tumor ablation (Nd:YAG laser, PDT, cryoablation) or expandable metal/plastic stents; feeding gastrostomy or jejunostomy for anorexia/dysphagia/malnutrition, but placement of a GASTROSTOMY preoperatively may compromise the gastric vasculature and interfere with gastric-conduit reconstruction and SHOULD BE AVOIDED (feeding jejunostomy is generally preferred for postoperative nutritional support; multidisciplinary expertise is recommended before percutaneous gastrostomy).

Diagnose acute pancreatitis (AP) by the Atlanta criteria (2 of 3: characteristic epigastric/LUQ pain, lipase or amylase >3x ULN [lipase preferred for specificity/duration], or characteristic imaging). ACG 2024 stratifies severity risk using SIRS on admission plus bedside risk factors, rising/elevated BUN, rising/elevated hematocrit (>44), obesity (BMI>30), extrapancreatic fluid collections/pleural effusion/infiltrates, altered mental status, and older age/comorbidities, rather than mandating a formal BISAP or APACHE II composite score. Give moderately aggressive lactated Ringer's, most important in the first 6-12 hours, reassessing volume status/BUN/HCT at 6 hours (further aggressive hydration has little added benefit after 24-48h). Start oral low-fat solid food within 24-48h as tolerated in mild disease; if enteral feeding is needed for moderately severe/severe disease, prefer nasogastric over nasojejunal with small-peptide/medium-chain-triglyceride formula and continuous (not bolus/cyclic) feeding; avoid parenteral nutrition if possible. Do not give prophylactic antibiotics, even in severe disease or sterile necrosis; reserve antibiotics for suspected infected necrosis (typically arising 10-14 days in), and choose agents that penetrate pancreatic necrosis while together covering both gut-derived gram-negative enterics and anaerobes, a carbapenem supplies this as monotherapy, whereas a fluoroquinolone or a third-or-higher-generation cephalosporin must be combined with metronidazole; metronidazole alone (anaerobic cover only), or a cephalosporin or a quinolone alone, does not adequately treat infected necrosis. Perform cholecystectomy preferably before discharge for mild acute biliary pancreatitis, and after a second unexplained AP episode even without identified gallstones; reserve ERCP within 24h for AP complicated by cholangitis, with rectal indomethacin +/- pancreatic duct stent and periprocedural hydration to reduce post-ERCP pancreatitis risk. Check triglycerides when gallstones/alcohol are absent (>1000 mg/dL supports a hypertriglyceridemia etiology). For stable pancreatic necrosis, defer surgical, radiological, or endoscopic intervention 4-6 weeks to allow walling-off (step-up approach).

After polyp removal, assign the next colonoscopy surveillance interval using USMSTF 2020 based on polyp number, size, and histology (e.g., 1-2 tubular adenomas <10 mm 7-10 years; 3-4 tubular adenomas <10 mm 3-5 years; 5-10 tubular adenomas <10 mm, any adenoma ≥10 mm, or adenoma with tubulovillous/villous histology or high-grade dysplasia 3 years; >10 adenomas 1 year with polyposis evaluation; and for serrated polyps, 1-2 sessile serrated lesions <10 mm 5-10 years, 3-4 sessile serrated lesions <10 mm or a hyperplastic polyp ≥10 mm 3-5 years, and a sessile serrated lesion ≥10 mm or with dysplasia or a traditional serrated adenoma 3 years), and apply the shortest interval indicated when findings are mixed. Confirm complete resection and adequate prep before applying an interval, and use site-check/tumor-board pathways for piecemeal resection and malignant (T1) polyps. Refer for genetic evaluation when Lynch, FAP/AFAP/MAP, or serrated polyposis syndrome criteria are met.

For right upper quadrant pain, characterize the pattern (acute vs chronic, post-meal vs unrelated, with vs without fever/jaundice) and triage acute red-flag presentations (Murphy sign, Charcot's triad, painless jaundice with weight loss, pregnancy with LFT/coagulation derangement) to the ED. Obtain labs (CBC, CMP with LFTs, lipase, urinalysis, pregnancy test in reproductive-age women) and RUQ ultrasound as first imaging, then direct further workup by ultrasound findings, cholecystectomy for acute cholecystitis, MRCP for suspected choledocholithiasis based on risk stratification (e.g., high-risk criteria including CBD dilation >6 mm, bilirubin >4 mg/dL, or gallstone pancreatitis), CCK-HIDA/GBEF for acalculous functional gallbladder disorder, and cross-sectional imaging for liver masses or other pathology.

All patients meeting clinical criteria for, or carrying a pathogenic germline variant of, a hereditary GI cancer syndrome should have pre- and post-test genetic counseling, and at-risk first-degree relatives should be offered genetic testing. Syndrome-specific surveillance: LYNCH SYNDROME, colonoscopy at least every 2 years (annual colonoscopy should be considered in confirmed mutation carriers), beginning at age 20-25 years, or 2-5 years before the earliest CRC diagnosis in the family if that was before age 25; baseline EGD with gastric biopsy and test-and-treat for H. pylori at age 30-35, with ongoing upper-GI surveillance every 3-5 years where family history of gastric/duodenal cancer exists; annual endometrial biopsy and transvaginal ultrasound from age 30-35, with prophylactic hysterectomy/bilateral salpingo-oophorectomy offered after childbearing; surveillance BEYOND population-based recommendations for the urinary tract, pancreas, breast and prostate is NOT recommended unless supported by family history. CLASSIC FAP, annual sigmoidoscopy or colonoscopy beginning at puberty; colectomy indicated for documented/suspected cancer or significant symptoms (absolute), or for relative indications such as multiple adenomas >6 mm or a significant increase in adenoma number that make endoscopic control unfeasible; upper-GI surveillance by EGD/duodenoscopy from age 25-30, repeated every 0.5-4 years by Spigelman stage, plus annual thyroid ultrasound. AFAP, surveillance by colonoscopy (not sigmoidoscopy, as polyps are right-sided) with polypectomy every 1-2 years, beginning in the late teens to early 20s; upper-GI surveillance by EGD/duodenoscopy from age 25-30, repeated every 0.5-4 years by Spigelman stage, plus annual thyroid ultrasound (as for classic FAP). MUTYH-ASSOCIATED POLYPOSIS (biallelic MUTYH), colonoscopy every 1-2 years beginning at age 25-30; upper-GI surveillance by EGD/duodenoscopy from age 25-30, repeated every 0.5-4 years by Spigelman stage, plus annual thyroid ultrasound (as for classic FAP). SERRATED POLYPOSIS SYNDROME, colonoscopy every 1-3 years with attempted removal of all polyps >5 mm.