RESUMEN
BACKGROUND: People living with HIV (PLWH) have substantially increased incidence of anal precancer and cancer. There are very little data regarding genomic disturbances in anal precancers among PLWH. Here, we identified specific chromosomal variants in anal squamous intraepithelial lesions. METHODS: We collected 63 anal biopsy specimens (27 low-grade intraepithelial lesions [LSIL] and 36 high-grade intraepithelial lesions [HSIL]) from PLWH obtained as part of anal cancer screening in our NYC-based health system. Data on patient demographics, anal cytological and high-risk human papillomavirus (HR-HPV) diagnoses were collected. Specimens were tested for a panel of chromosomal alterations associated with HPV-induced oncogenesis using Fluorescence In-Situ Hybridization (FISH) and analyses compared the associations of these alterations with clinical characteristics. RESULTS: Gains of 3q26, 5p15, 20q13 and cen7 were detected in 42%, 31%, 31%, and 19% of HSIL compared to 7%, 0%, 4%, and 0% of LSIL, respectively. Where at least one abnormality was seen, 89% had a 3q26 gain. In lesions with 5p15 gains, 20q13 gains co-occurred in 91% of cases, while cen7 gain only co-occurred with the other three alterations. Sensitivity and specificity of any alteration to predict HSIL was 47% (95% CI: 30-65%) and 93% (95% CI: 76%-99%) respectively. CONCLUSIONS: Genomic alterations seen in HPV-associated cancers may help distinguish anal LSIL from HSIL. 3q26 amplification may be an early component of anal carcinogenesis, preceding 5p16, 20q13 and/or chr7. IMPACT: We share insights on potential genomic biomarkers for discriminating high-risk anal precancers.
RESUMEN
Metastatic urachal carcinoma is a rare, understudied, and aggressive malignancy with limited treatment options. Histologically, urachal carcinomas resemble enteric adenocarcinomas and anecdotally respond to systemic therapies utilized in colorectal cancer. Targeted exome sequencing of archival primary tumor tissue from a patient with metastatic urachal cancer revealed EGFR amplification and wild-type KRAS. The patient was treated with cetuximab, a monoclonal antibody directed against EGFR, as a single agent, and achieved a response lasting more than 8 mo. Subsequent whole-exome sequencing revealed no additional alterations likely to be associated with cetuximab sensitivity. Formalin-fixed, paraffin-embedded tumor specimens from nine additional urachal cancers were subjected to targeted exome sequencing. Mitogen-activated protein kinase (MAPK) pathway mutations were found in four of the nine samples, but no EGFR amplification was detected. Importantly, APC mutations were detected in two of the nine patients. To our knowledge, this is the first report of a response to single-agent cetuximab in a patient with metastatic urachal cancer and of molecular analysis to probe the basis for sensitivity. On the basis of these findings and the histologic, and now genomic, similarities with colorectal cancer, monoclonal antibodies directed at EGFR could be used in the treatment of metastatic urachal cancer. PATIENT SUMMARY: Urachal cancers are morphologically and genomically similar to colon adenocarcinomas and may respond to drugs targeting the epidermal growth factor receptor.
