Annette Arndt

Introduction: Pemetrexed, an antifolate, is a standard therapy for lung adenocarcinoma (LUAD). Since folic acid is vital for nucleic acid metabolism, disrupting its pathway affects both tumor cells and regenerating healthy cells. The PemToxTrial examined the impact of pemetrexed on severe hematotoxicity and mortality. Methods: This retrospective analysis included 136 LUAD patients (UICC8 stage IVA/B) receiving palliative treatment. Ninety-two patients received pemetrexed-based therapy, while 44 received pemetrexed-free treatment (68 and 38 with immune-checkpoint inhibitors). Bone metastasis (BM) was present in 47 patients in the pemetrexed group and 22 in the comparison group. The primary endpoint was grade III–V hematotoxicity; secondary endpoints included mortality, progression-free survival (PFS), and overall survival (OS). Hematologic outcomes following a subsequent change in clinical practice were prospectively assessed in a post-implementation cohort of 15 patients with bone-metastatic LUAD receiving pemetrexed-free regimens. Results: Median age was 66 years, 59.6% were male and median follow-up was 13.5 months. Grade III-V hematotoxicity was most frequent (81%) in patients with BM receiving pemetrexed (n = 47), significantly higher than in other subgroups (p < 0.0001). Mortality was also increased in this group (66% vs. 29%, p < 0.0001), with hematotoxicity directly contributing to death in 42% versus 11.5% of cases. PFS was significantly inferior (5.2 vs. 8.6 months). Multivariable analysis identified BM as the only independent predictor of severe hematotoxicity and mortality. Only a mutational burden of ≥4 potential driver alterations was associated with inferior PFS. Bone-derived total lesion glycolysis (TLG) on PET-CT strongly correlated with high-grade hematotoxicity (p < 0.0001). Conclusions: The PemToxTrial identified a strong association between pemetrexed exposure, bone metastases, and severe hematotoxicity, supporting further prospective evaluation of bone metastasis status as a potential clinical risk factor for treatment-associated hematotoxicity.

Background: Malignant neoplasms of the salivary glands are rare, and therapeutic options are limited. Results from recently published studies indicate a possible use for checkpoint inhibition in a subset of patients, but there are no established criteria for programme cell death ligand 1 (PD-L1) scoring in salivary gland carcinomas (SGCs). Methods: In this retrospective study, we present a cohort of 94 SGC patients with full clinical follow-up. We included 41 adenoid cystic carcinomas (AdCC), 21 mucoepidermoid carcinomas (MEC), 16 acinic cell carcinomas (ACC), 12 adenocarcinomas, not otherwise specified (AC, NOS), 2 epithelial-myoepithelial carcinomas (EMC), one salivary duct carcinoma (SDC), and one carcinoma ex pleomorphic adenoma (CA ex PA). Subsequent histopathological analysis was performed with special emphasis on the composition of the immune cell infiltrate (B-/T-lymphocytes). We assessed PD-L1 (SP263) on full slides by established scoring criteria: tumor proportion score (TPS), combined positivity score (CPS) and immune cell (IC) score. Results: We identified significantly elevated CD3+, TP, CP, and IC scores in AC, NOS compared to AdCC, MEC, and ACC. CPS correlated with node-positive disease. Moreover, AC, NOS displayed IC scores of 2 or 3 in the majority (67%) of cases (p = 0.0031), and was associated with poor prognosis regarding progression-free (PFS) (p < 0.0001) and overall survival (OS) (p < 0.0001). CPS correlated with strong nuclear or null p53 staining in AC, NOS but not in other SGCs. Long-lasting partial remission could be achieved in one AC, NOS patient who received Pembrolizumab as third-line therapy. Conclusions: The current study is the first to investigate the use of established scoring criteria for PD-L1 expression in malignant salivary gland tumors. Our findings identify unique characteristics for AC, NOS among the family of SGCs, as it is associated with poor prognosis and might represent a valuable target for immune checkpoint inhibition.

Up to 50% of penile squamous cell carcinomas (pSCC) develop in the context of high-risk human papillomavirus (HR-HPV) infection. Most of these tumours have been reported to show basaloid differentiation and overexpression of tumour suppressor protein p16INK4a. Whether HPV-triggered carcinogenesis in pSCC has an impact on tumour aggressiveness, however, is still subject to research. In tissue specimens from 58 patients with surgically treated pSCC between 1995 and 2012, we performed p16INK4a immunohistochemistry and DNA extraction followed by HPV subtyping using a PCR-based approach. The results were correlated with histopathological and clinical parameters. 90.4% of tumours were of conventional (keratinizing) subtype. HR-HPV DNA was detected in 29.3%, and a variety of p16INK4a staining patterns was observed in 58.6% of samples regardless of histologic subtype. Sensitivity of basaloid subtype to predict HR-HPV positivity was poor (11.8%). In contrast, sensitivity and specificity of p16INK4a staining to predict presence of HR-HPV DNA was 100% and 57%, respectively. By focussing on those samples with intense nuclear staining pattern for p16INK4a, specificity could be improved to 83%. Both expression of p16INK4a and presence of HR-HPV DNA, but not histologic grade, were inversely associated with pSCC tumour invasion (p = 0.01, p = 0.03, and p = 0.71). However, none of these correlated with nodal involvement or distant metastasis. In contrast to pathological tumour stage, the HR-HPV status, histologic grade, and p16INK4a positivity failed to predict cancer-specific survival. Our results confirm intense nuclear positivity for p16INK4a, rather than histologic subtype, as a good predictor for presence of HR-HPV DNA in pSCC. HR-HPV / p16INK4a positivity, independent of histological tumour grade, indicates a less aggressive local behaviour; however, its value as an independent prognostic indicator remains to be determined. Since local invasion can be judged without p16INK4a/HPV-detection on microscopic evaluation, our study argues against routine testing in the setting of pSCC.