Prevalence and significance of HPV DNA detection below the clinical threshold of the commercial kit Alinity m HR-HPV assay (Abbott).

The positive clinical threshold of human papillomavirus (HPV) tests validated for primary cervical cancer screening (CCS) is designed to offer an optimal balance between clinical sensitivity and specificity. However, there may be a gap between the analytical sensitivity of the test and the positive clinical threshold, referred to here as the "gray-zone." This study aims to determine the prevalence and significance of HPV results obtained in the gray-zone in routine practice. Cervical samples obtained in our institution for CCS over a 22-month-period were tested with the Alinity m HR-HPV Assay (Abbott). Clinical and biological data, including cytological results and patients' HPV history were collected. Of the 6101 samples collected, 1.7% had an HPV result in the gray-zone (102 patients). The proportion of gray-zone results varied according to HPV genotype, reaching 11.8% of samples with detectable HPV DNA in the case of HPV31/33/52/58 genotypes. Reflex cytologies showed no abnormalities or Atypical Squamous Cells of Undetermined Significance results in 74.6% and 17.9% of cases, respectively. A previous or subsequent HPV-positive result with a (possibly) identical genotype was observed in 58% and 38% of cases, respectively. Two women with a history of persistent HPV detection had a CIN2+ lesion 1 year after the gray-zone result. In conclusion, the proportion of HPV results in the gray-zone varies according to genotype. No cytological abnormality is observed in the majority of cases, but a few rare patients with a history of persistent HPV infection should be closely monitored even if the HPV result is transiently located in the gray-zone.

Temporal and spatial heterogeneity of HER2 status in metastatic colorectal cancer.

BACKGROUND: HER2-targeted therapies have recently emerged as an option in the management of metastatic colorectal cancer (mCRC) overexpressing HER2. However, data regarding HER2 status in primary CRC and its corresponding liver metastases are limited, potentially influencing clinical decisions. Therefore, the aim of this study was to compare the HER2 status in primary CRC and paired liver metastases. METHODS: Patients with mCRC who were operated from their primary colorectal cancer and their corresponding synchronous or metachronous liver metastases, in the digestive surgery department of Besançon University Hospital, between April 1999 and October 2021, were included. Tissue microarrays were constructed from matched primary CRC and liver metastastic tissue samples. HER2 status was assessed by immunohistochemistry and in situ hybridization according to Valtorta's criteria. RESULTS: A series of 108 paired primary CRC and liver metastases, including a series of multiple liver metastases originating from the same patients (n = 24), were assessed. Among the primary CRC, 89 (82.4%), 17 (15.8%) and 2 (1.8%) cases were scored 0, 1 + and 2 + respectively. In liver metastases, 99 (91.7%), 7 (6.5%) and 2 (1.8%) were scored 0, 1 + and 2, respectively. Overall, there was a 19% discrepancy rate in HER2 status between primary CRC and metastases, which increased to 21% in cases with multiple synchronous or metachronous liver metastases in a given patient. No significant difference was found between metachronous and synchronous metastases regarding the HER2 status (p = 0.237). CONCLUSIONS: Our study highlights the temporal and spatial heterogeneity of HER2 status between primary CRC and corresponding liver metastases. These findings raise the question of a sequential evaluation of the HER2 status during disease progression, to provide the most suitable treatment strategy.

Evaluation of immune infiltrate according to the HER2 status in colorectal cancer.

BACKGROUND AND AIMS: In colorectal cancer (CRC), HER2 targeting is a promising treatment and immune infiltrate is an important area of research and strategy. Data regarding HER2 status and immune infiltrate are lacking. The aim of this study was to compare the immune infiltrate between HER2 amplified and non-amplified categories in proficient MisMatchRepair (pMMR)/microsatellite stable (MSS) CRC. METHODS: HER2 immunohistochemistry (IHC) and fluorescence in situ hybridization were performed in a retrospective series of 654 CRC. Lymphocyte infiltrate was analysed by anti-CD3, CD8 and CD4 IHC and evaluated digitally using QuPath software. RESULTS: Among the 654 CRC, we first observed a decreased CD3+ and CD8+ infiltrate between HER2 amplified (all IHC 3+ except one 2+) and non-amplified HER2 2+ IHC CRC (p = 0.059 and 0.072 respectively). A supplementary analysis of 258 pMMR/MSS CRC from the previous cohort, displaying all the IHC scores (0, 1+, 2+, 3+), showed a lower CD3+ infiltrate between HER2 amplified versus HER2 0 (p = 0.002), 1+ (p = 0.088) and non-amplified 2+ (p = 0.081) IHC cases. CONCLUSIONS: Our original findings suggest that in pMMR/MSS CRC, the immune infiltrate is reduced in HER2 amplified versus other HER2 categories. These data might be useful for future strategies combining anti-HER2 treatments and immune checkpoint inhibitors and need to be confirmed in larger CRC cohorts.