Medical and molecular traits of ALK-positive CRC sufferers
A complete evaluation of ALK-positive CRC instances was carried out by consolidating information from Solar Yat-sen College Most cancers Middle (SYSUCC; N = 6) spanning from December 2020 to January 2023, together with data extracted from beforehand printed instances (N = 9)5,6,7,8,9. Affected person traits of all included sufferers (N = 15) are detailed in Supplementary Desk 1. The median age at analysis for the cohort was 53 years (starting from 43 to 87 years), with feminine sufferers comprising 53% of the instances. Notably, most sufferers (N = 11, 73.3%) offered with right-sided major colon most cancers, with 80% (N = 12) exhibiting adenocarcinoma histology. Probably the most prevalent kind of ALK fusion was EML4-ALK, accounting for 40% of sufferers. Of observe, Serine/arginine-rich splicing issue 7 (SRSF7) was recognized as a brand new fusion accomplice for ALK in Case 6 (C6). Microsatellite steady (MSS) standing was noticed in 12 sufferers, whereas one affected person displayed MSI-H, and the standing of two sufferers is unknown. Over half of the included sufferers (N = 9) had a number of metastatic websites, with information lacking for 5 sufferers. Three sufferers beforehand obtained Cetuximab, whereas 4 have been handled with Bevacizumab. By way of ALKi therapy, three sufferers (27%) have been handled with Alectinib, two sufferers (18%) with Ensartinib, one affected person (9%) with Entrectinib, 4 sufferers (37%) with Crizotinib, and one affected person (9%) with Ceritinib. After illness development underneath first-line ALKi, 5 sufferers (46%) obtained subsequent traces of ALKi therapy. Alectinib was administered after Crizotinib in three sufferers, Brigatinib was utilized following Ensartinib in a single affected person, and Ceritinib was launched after the failure of upfront Alectinib in a single affected person. Apparently, all included ALK fusion-positive CRC sufferers didn’t harbor activated mutations in RAS/RAF genes, that are the predominant driver gene mutations in CRC. In the meantime, Case 3 (C3) exhibited ERBB2 amplification, FGFR1 amplification, and CDK12 amplification, whereas Case 5 (C5) harbored an RSPO2 fusion.
Exercise and efficacy of ALKi
Desk 1 offers an outline of the sufferers who underwent ALKi remedy. A complete of 11 sufferers obtained ALKi therapy, together with two sufferers from the SYSUCC cohort and 9 sufferers from printed research. The median progression-free survival (PFS) for the primary ALKi therapy was 4.5 months (Supplementary Fig. 2). Amongst these sufferers, two (18%) achieved a whole response, whereas 5 (45%) achieved a partial response (PR). The target response price (ORR) was 63%, and three sufferers (27%) reached steady illness (SD), leading to a illness management price (DCR) of 90%. Just one affected person (9%) skilled illness development through the preliminary analysis.
Among the many two sufferers who obtained second-line ALKi therapy, P2 skilled progressive illness (PD) after 0.5 months of Alectinib therapy. Subsequently, this affected person underwent Lorlatinib therapy for 11.5 months earlier than passing away. In the meantime, C5 obtained Brigatinib and Lorlatinib as a third- and fourth-line of ALKi therapy, respectively. As of the cutoff date, all sufferers had skilled PD following first-line ALKi therapy, with a complete of 11 sufferers (85%) succumbing to the illness.
The swimmer plot in Supplementary Fig. 3 additional illustrates the scientific therapy obtained by the six sufferers: C1, C2, C3, C5, P2, and P4. Amongst these, C1, C2, and C3 obtained Bevacizumab, whereas C3, C5, P2, and P4 have been handled with Cetuximab. Provided that the addition of Cetuximab for ALK fusion-positive CRC sufferers yielded suboptimal outcomes, we additional in contrast the PFS of various focused therapies whatever the therapy line. As proven in Supplementary Fig. 4, the PFS of sufferers who obtained Cetuximab was considerably worse than those that obtained Bevacizumab (hazard ratio [HR] 4.41, 95% CI [0.78, 24.82], log-rank P = 0.021).
Consultant case of ALK fusion-positive CRC receiving ALKi sequential technique
Determine 1 presents an in depth timeline of the scientific historical past of a consultant case, C5, a 43-year-old male recognized with superior CRC. The affected person developed liver metastases following adjuvant XELOX chemotherapy. Subsequent NGS testing of the first tumor revealed the presence of EML4 (exon7)-ALK (exon20) fusion, which is notably distinct from EML4-ALK V1 (exon 13 of EML4 fused to exon 20 of ALK) or V3 (exon 20 of EML4 fused to exon 20 of ALK) variants. Apart from, NGS testing additional revealed that the affected person harbored NUDCD1-RSPO2 fusion, whereas FGFR gene fusion was not detected. Given his RAS/RAF wild-type standing, Cetuximab plus FOLFIRI was initiated. Nonetheless, fast development was noticed after simply two cycles of chemotherapy. Subsequent, second-generation ALKi, Ensartinib, was administered, and the affected person achieved PR standing inside one month. Regrettably, after 5 months, his liver metastases confirmed development, and the affected person opted for a scientific trial involving a third-generation ALKi, which additionally proved ineffective. The affected person was then given Fruquintinib as a part of the usual third-line therapy routine for CRC. However, tumor development was detected, and a liver biopsy was really helpful, contemplating the opportunity of ALK inhibitor resistance. A biopsy of the liver metastases and NGS testing revealed the presence of the ALK L1196M mutation, sometimes called a gatekeeper mutation, along with EML4 (exon7)-ALK (exon19) fusion. Based mostly upon earlier research that confirmed that Brigatinib and Lorlatinib are efficient towards ALK L1196M resistance mutations10,11, Brigatinib was initiated, and the affected person achieved good illness management and skilled aid from stomach ache and a major discount in serum CEA ranges after receiving Brigatinib for one month. Nonetheless, after 3 months of initiating Brigatinib therapy, illness development was noticed, accompanied by a major elevation in CEA ranges. Subsequently, the affected person was switched to Lorlatinib and has but to exhibit illness development up to now.
