Rodrigo Arrangoiz MS, MD, FACS, FSSO

10/09/2025

In p16+ OPSCC, does any efficacy endpoint favor cetuximab-RT over cisplatin-RT? Best answer: No Why: Neither OS, PFS, nor LRC improved with cetuximab: All favored cisplatin PubMed+1 When to deviate: Only with absolute cisplatin ineligibility PMC: Discuss RT + cetuximab (Bonner) or altered-fractionation RT Pitfalls: Extrapolating the Bonner 2006 RT + cetuximab vs RT-alone result: To cisplatin-eligible patients is incorrect New England Journal of Medicine Bonner: 5-yr OS 45.6% with RT + cetuximab vs 36.4% RT alone: Not a comparison to cisplatin Under-discussing ototoxicity / renal toxicity risks with cisplatin: …...

In p16+ OPSCC, does any efficacy endpoint favor cetuximab-RT over cisplatin-RT? Best answer: No Why: Neither OS, PFS, nor LRC improved with cetuximab: All favored cisplatin PubMed+1 When to devia…

10/08/2025

HPV Positive Oropharyngeal Squamous Cell Carcinoma (HPV⁺ OPSCC): Radiation therpay (RT) + cetuximab vs RT + cisplatin (why substitution fails) Clinical rule: In cisplatin-eligible HPV⁺ oropharynx cancer: Do not replace cisplatin with cetuximab: To “de-intensify” Two large phase III trials showed: Worse survival and control with cetuximab RTOG-1016 (Lancet 2019; non-inferiority trial): Design: RT + cetuximab vs RT + cisplatin 100 mg / m² × 2 in HPV⁺ OPSCC Primary endpoint OS: Non-Inferiority (NI) margin HR 1.45 Results (median f/u ~ 4.5 y): 5-yr OS: 77.9% cetuximab vs 84.6% …...

HPV Positive Oropharyngeal Squamous Cell Carcinoma (HPV⁺ OPSCC): Radiation therpay (RT) + cetuximab vs RT + cisplatin (why substitution fails) Clinical rule: In cisplatin-eligible HPV⁺ oropharynx …

10/07/2025

Tethering and Rolling (milliseconds–seconds): What happens: Fast blood flow makes first contact fleeting: Cells need “molecular Velcro” that works under shear. Selectins on endothelium: E-selectin: Induced by TNF-α / IL-1 P-selectin: Rapidly mobilized from Weibel–Palade bodies Also on platelets Ligands on leukocytes: PSGL-1 and other sialyl-Lewis^x (sLe^x): Decorated glycoproteins L-selectin (CD62L) is on leukocytes: Not endothelium: It helps secondary capture / rolling: Leukocyte–leukocyte interactions Binds Peripheral Node Addressin on High Endothelial Venules (PNAd on HEVs) Mechanics: “Catch bonds” let cells roll, sampling endothelium for activating cues…...

Tethering and Rolling (milliseconds–seconds): What happens: Fast blood flow makes first contact fleeting: Cells need “molecular Velcro” that works under shear. Selectins on endothelium: E-selecti…

10/06/2025

When resection is performed for patients with thyroid cancer ≤ 2 cm without gross extra-thyroidal extension (cT1) and without metastases (cN0M0): The initial surgical procedure should be a thyroid lobectomy: Unless there are bilateral cancers or other indications to remove the contralateral lobe: Strong recommendation, Moderate certainty evidence For patients with low risk, unilateral thyroid cancer > 2 and ≤ 4 cm (cT2N0M0): Thyroid lobectomy may be the preferred initial surgical treatment due to significantly lower risk and side effects: However, the patient and treatment team may adopt total thyroidectomy to enable RAI administration and / or enhance follow-up based on disease features, suspicious contralateral nodularity, and / or patient preferences…...

When resection is performed for patients with thyroid cancer ≤ 2 cm without gross extra-thyroidal extension (cT1) and without metastases (cN0M0): The initial surgical procedure should be a thyroid …

10/06/2025

Who was studied? Population: Completely resected, intermediate-risk HNSCC of: Oral cavity, oropharynx, or larynx: Hypopharynx excluded Intermediate-risk factors included any of: Pernineural invasion (PNI) Lymphovascular ivasion (LVI) ≥ 2 lymph nodes (LNs) (all < 6 cm) or one LN > 3 cm (no extranodal extension (ENE)) Close margin(s) < 5 mm or focally positive then re-resected negative pT3 to pT4a primary, or T2 oral cavity with DOI > 5 mm ozarkscancerresearch.org Key baseline notes: Majority HPV-negative (~ 80%) Oral cavity ~ 64% EGFR high expression in ~ 85%...

http://arrangoizmd.com/2025/10/06/rtog-0920-nrg-rtog-0920/

Who was studied? Population: Completely resected, intermediate-risk HNSCC of: Oral cavity, oropharynx, or larynx: Hypopharynx excluded Intermediate-risk factors included any of: Pernineural invas…

10/05/2025

What to monitor (and when): Before starting (≤ 7 days prior): BMP / eGFR + electrolytes: Cr, BUN, Mg, K, Ca, Na, PO₄ Urinalysis if concern for renal injury Why: Baseline renal reserve; cisplatin causes salt wasting (especially Mg) and AKI eviQ CBC with differential: Why: Myelosuppression risk DailyMed+1 Audiology (baseline audiogram): Why: Ototoxicity risk: Establish baseline threshold: Audiology societies and monographs recommend baseline and interval monitoring American Academy of Audiology+2audiology-web.s3.amazonaws.com+2 Medication review and vitals / weight.: Hold / avoid nephrotoxins: NSAIDs, IV contrast, aminoglycosides…...

http://arrangoizmd.com/2025/10/05/what-to-monitor-during-chemoradiation-crt-with-cisplatin-for-head-and-neck-cancer/

What to monitor (and when): Before starting (≤ 7 days prior): BMP / eGFR + electrolytes: Cr, BUN, Mg, K, Ca, Na, PO₄ Urinalysis if concern for renal injury Why: Baseline renal reserve; cisplatin …

10/04/2025

10/04/2025

Complement System: The complement cascade is a system of immune proteins: That activates in a cascade-like fashion: To fight infection and promote tissue repair: But also contributes to inflammation and disease when overactivated It works via three pathways (classic, lectin, alternative): That converge to create inflammatory fragments called: Anaphylatoxins and form a membrane attack complex (MAC) that can kill pathogens Beyond infection: Complement plays roles in clearing cellular debris, facilitating tissue regeneration, and regulating neuronal function: But inappropriate activation can cause: Chronic pain, autoimmune disease, and organ damage…...

Complement System: The complement cascade is a system of immune proteins: That activates in a cascade-like fashion: To fight infection and promote tissue repair: But also contributes to inflammatio…

10/04/2025

Hepatic acute-phase response (APR) in trauma — what rises, what falls, and why it matters What it is? Within hours of significant injury: IL-6 (with TNF-α / IL-1) shifts hepatocyte transcription toward acute-phase proteins (APPs): Away from constitutive proteins This fuels host defense: Opsonization, complement, coagulation control, metal sequestration: But distorts common labs Protein Kinetics after trauma Key functions Clinical pearls CRP...

Hepatic acute-phase response (APR) in trauma — what rises, what falls, and why it matters What it is? Within hours of significant injury: IL-6 (with TNF-α / IL-1) shifts hepatocyte transcription to…

10/03/2025

Ebb phase: First 6 to 24 hours to 48 hours: “Shock, conserve” Characterize by: Hypometabolism ↓O₂ consumption Relative hypothermia Neuroendocrine surge: Catecholamines Cortisol Glucagon The innate immune system is triggered: Early TNF-α / IL-1 release: Begins the inflammatory cascade / response PMC+1 Flow phase: Catabolic sub-phase: From days ~ 1 to 7: “Hypermetabolism, mobilize” Characterize by: ↑O₂ consumption Hyperglycemia Insulin resistance Proteolysis TNF-α and IL-1 drive the early wave: Rapidly followed by IL-6: Acute-phase switch IL-8: Neutrophil recruitment (PMN chemotaxis) Angiogenesis Counter-regulators like IL-10: …...

Ebb phase: First 6 to 24 hours to 48 hours: “Shock, conserve” Characterize by: Hypometabolism ↓O₂ consumption Relative hypothermia Neuroendocrine surge: Catecholamines Cortisol Glucagon The innate …

10/03/2025

Leukotrienes: Are a family of potent inflammatory lipid mediators: Derived from arachidonic acid in white blood cells (leukocytes) and other immune cells Produced rapidly in response to injury, infection, or allergens Leukotrienes: Act as local hormones: That help regulate immune and inflammatory responses Biosynthesis pathway: Leukotrienes are produced through the 5-lipoxygenase (5-LO) pathway An increase in intracellular calcium: Activates the enzyme phospholipase A2 (cPLA2): Which releases arachidonic acid (AA) from cell membrane phospholipids AA is converted into an unstable epoxide intermediate: Leukotriene A4 (LTA4): Through a two-step process catalyzed by the…...

Leukotrienes: Are a family of potent inflammatory lipid mediators: Derived from arachidonic acid in white blood cells (leukocytes) and other immune cells Produced rapidly in response to injury, inf…

10/02/2025

Post-op intermediate-risk pathology: Perineural Invasion (PNI) Lymphovascular Invasion (LVI) pT3 ENE-negative Negative margins Standard adjuvant plan: Postoperative radiation therapy (RT) alone (no concurrent cisplatin) Why?: Two landmark randomized trials established who benefits from adding cisplatin to adjuvant RT: EORTC 22931 (Bernier, NEJM 2004): Showed CRT > RT overall in a broad high-risk cohort: Improving PFS / OS: Its Kaplan–Meier curves separate for combined therapy New England Journal of Medicine+2PubMed+2 RTOG 9501 (Cooper, NEJM 2004; 10-yr update 2012): In the entire randomized population: CRT did not significantly improve OS / DFS vs RT alone: …...

Post-op intermediate-risk pathology: Perineural Invasion (PNI) Lymphovascular Invasion (LVI) pT3 ENE-negative Negative margins Standard adjuvant plan: Postoperative radiation therapy (RT) alone (n…