Baral, Binav

Background/Objectives: Tumor-infiltrating lymphocyte (TIL) therapy is an important option for patients with metastatic melanoma progressing after standard systemic therapy, but real-world data on treatment delivery, toxicity monitoring, and immune recovery remain limited. We evaluated clinical outcomes, treatment tolerance, immune reconstitution, and cardiac biomarker dynamics across three Mayo Clinic sites. Methods: We retrospectively analyzed adults with metastatic melanoma who received lymphodepleting chemotherapy followed by TIL infusion and high-dose interleukin-2 (IL-2) between April 2024 and December 2025. Clinical outcomes, treatment delivery, and adverse events were assessed. Longitudinal immune monitoring included CD4 and CD8 T-cell counts, CD4:CD8 ratio, and immunoglobulin G (IgG) at baseline and follow-up. In a prespecified cardiac sub-cohort, high-sensitivity troponin (hs-Tn) was measured during IL-2 administration to evaluate associations with cardiac events and IL-2 interruption. Results: Thirty-six patients underwent TIL infusion. The objective response rate was 50.0%, including complete responses in 13.9%, and the disease control rate was 72.2%. Median progression-free survival was 3.61 months, and median overall survival was 12.94 months. M1d disease was associated with inferior overall survival on univariable analysis (HR 6.55, 95% CI 2.03–21.17; p = 0.002), with attenuation after multivariable adjustment. Receipt of ≥3 IL-2 doses was associated with longer overall survival on univariable analysis (HR 0.20, 95% CI 0.06–0.64; p = 0.007), but this association also attenuated after adjustment. Longitudinal immune monitoring demonstrated persistent CD4 lymphopenia through 6 months, sustained inversion of the CD4:CD8 ratio, and declining IgG at months 3 and 6. In the cardiac sub-cohort (24 patients; 87 IL-2 doses), post-dose hs-Tn ≥15 ng/L was associated with clinically significant cardiac events (OR 9.6, 95% CI 1.5–60.6; p = 0.016) and IL-2 interruption (OR 3.4, 95% CI 1.1–10.7; p = 0.036). For cardiac events, hs-Tn ≥15 ng/L had 100% sensitivity and 100% negative predictive value. Conclusions: In routine practice, TIL therapy was feasible and active in metastatic melanoma. M1d disease identified a subgroup with poor survival, peri-dose hs-Tn showed promise as a tool to support safer IL-2 delivery, and prolonged CD4 suppression with IgG decline suggests that recovery after TIL therapy extends beyond initial hematologic reconstitution. These findings support prospective validation of biomarker-guided IL-2 monitoring and extended post-treatment immune surveillance.

Management of locoregionally advanced human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV(+) OPSCC) can include induction chemotherapy followed by definitive chemoradiation. The standard induction regimen of cisplatin, docetaxel, and 5-fluorouracil (TPF) is associated with high toxicity. Given the chemosensitivity of HPV(+) OPSCC, platinum doublets are frequently used as induction therapy with potentially less toxicity. This retrospective study aimed to compare outcomes between treatment-naive HPV(+) OPSCC patients receiving induction TPF and those receiving an induction platinum doublet. Data collected included tumor characteristics, response after chemoradiation, hospitalization rates, and overall survival (OS). Fifty-five patients (18 TPF and 37 platinum doublet) were included. There was no significant difference in response after completion of definitive chemoradiation (TPF: CR 83.3%, PR 5.6%, progression or metastasis 11.1% vs. platinum doublet: CR 75.7%, PR 16.2%, progression or metastasis 8.1%; p = 0.5241). There were also no differences in hospitalizations for adverse events (38.9% in TPF vs. 40.5% in platinum doublet, p = 0.907) or recurrence (11.1% in TPF vs. 2.7% in platinum doublet, p = 0.198). The 5-year OS was 84.6% in the TPF group and 81.5% in the platinum doublet group (p = 0.581). Induction platinum doublet regimens offer comparable OS, response, and hospitalization rates to TPF in locally advanced HPV(+) OPSCC. Induction with a platinum doublet may be a viable de-escalation strategy for patients who are not candidates for TPF.

Caudal type homeobox 2 (CDX2) is an intestine-specific transcription factor that serves as a diagnostic marker of enteric differentiation and may also reflect tumor behavior and therapeutic susceptibility. Emerging evidence suggests that CDX2 expression may predict sensitivity to fluoropyrimidine-based therapy independent of tissue of origin. We report a retrospective case series of three patients with metastatic adenocarcinoma (aggressive variant prostate, minor salivary gland, and intestinal-type sinonasal tract) exhibiting strong CDX2 nuclear expression. In all cases, tumors were refractory to or lacked established standard systemic therapy. Treatment decisions were informed by the CDX2-positive enteric phenotype, leading to the initiation of fluoropyrimidine-based regimens. Response was assessed using PET-CT and MRI. All three patients achieved marked metabolic and clinical responses, including a sustained complete metabolic response in the prostate cancer case and durable disease control in the salivary gland and sinonasal tumors. These findings highlight CDX2 as a potential biomarker requiring validation, which may identify tumors intrinsically susceptible to fluoropyrimidines regardless of anatomical origin. CDX2 immunohistochemistry is widely available and inexpensive, and may complement genomic profiling in rare malignancies or in settings where standard treatment algorithms are limited. This report is hypothesis-generating and not intended to estimate response rates or treatment efficacy.