Colorectal adenocarcinomas diagnosed following a negative faecal immunochemical test show high-risk pathological features in a colon screening programme.

AIMS: The faecal immunochemical test (FIT) is used every 2 years to screen average-risk British Columbians aged 50-74 years, with follow-up colonoscopy for positive results. Non-screen-detected colorectal adenocarcinomas are defined as those detected within 25 months following a negative FIT. We aimed to more clearly characterise these malignancies. METHODS AND RESULTS: A medical chart and focused pathology review of colorectal malignancies from 926 individuals who completed FIT in the British Columbia Colon Screening Program in 2014, and whose pathology reports were available for review, was conducted. This cohort was divided into two groups: individuals with colorectal adenocarcinomas diagnosed following a positive FIT (screen-detected) and individuals with colorectal adenocarcinoma diagnosed within 25 months of a negative FIT (FIT-interval cancers). Rates of clinically relevant pathological parameters, as outlined in the American Joint Committee on Cancer (AJCC), 8th edition, were compared between the screen-detected and FIT-interval cancer groups. A total of 876 screen-detected and 50 FIT-interval cancers were identified. FIT-interval cancers exhibited higher rates of high-grade differentiation (including poorly differentiated and undifferentiated cases; P < 0.01) and aggressive histotype (signet ring cell and mucinous carcinomas; P < 0.01) than did screen-detected cancers after Bonferroni correction. Colorectal adenocarcinoma diagnosed after a negative FIT may therefore be associated with worse prognostic determinants than screen-detected cancers. CONCLUSION: FIT-interval cancers are associated with high-risk pathological features; the possibility that more aggressive, fast-growing lesions which arise in the interval after truly negative FITs cannot be ruled out. Further study of a larger cohort of FIT-interval cancers controlling for interaction among the different pathologic parameters will be undertaken.

Lurking below: massive choroidal invasion under a calcified tumor after attempted conservative therapy for retinoblastoma.

BACKGROUND: In the conservative management of retinoblastoma, detection of tumor activity beneath large, calcified tumors presents a challenging aspect of care as local consolidation is limited in this area. Routine imaging modalities, including magnetic resonance imaging, B-scan ultrasound, and optical coherence tomography, are also limited in providing appropriate surveillance for recurrent disease. MATERIALS AND METHODS: Medical records were reviewed to evaluate patients' demographic data, ophthalmic exams, imaging studies, and histopathologic reports. RESULTS: Three patients (two females and one male) were diagnosed with retinoblastoma (two bilateral and one unilateral) and managed with intravenous chemotherapy and local consolidation. In all three cases, the initial tumors regressed to form large, predominantly calcified tumors. However, it was observed that there continued to be nodular recurrences on the surface of the calcium without visible clinical activity at the base of the calcified lesion. All three cases ultimately required enucleation for these active nodular recurrences and massive choroidal invasion was noted under the calcified tumor. Ophthalmic exams and imaging studies did not provide consistent indication of choroidal disease in these cases, and the extensive calcification prevented detection of active disease at the tumor base on fundoscopy. CONCLUSIONS: Active choroidal disease at the base of large, calcified tumors cannot be ruled out with ophthalmologic examination and noninvasive imaging; suspicion of disease activity at the base should remain high for patients presenting with multiple recurrent nodules over a calcified tumor.

Loss of fundus view as an indication for secondary enucleation in retinoblastoma.

In this retrospective study, we evaluated loss of fundus view as an indication for secondary enucleation and associated histopathologic findings. Of 64 secondarily enucleated eyes, 24 were enucleated for loss of fundus view. Average time from loss of fundus view to enucleation was 4.7 months. Of these eyes, 22 had viable tumor cells on histopathology, but none had high-risk features. Loss of fundus view was a common indication for secondary enucleation after chemoreduction. Given the high prevalence of viable histopathologic tumor cells, enucleation for loss of fundus view should not be significantly delayed to decrease risk of high-risk tumor progression.