Overlapping symptoms of pelvic metastasis and degenerative spine disease in colorectal cancer: a challenge in early diagnosis

Abstract

Colorectal cancer (CRC) is the second leading cause of cancer mortality worldwide. 90% of CRC-related deaths are due to metastasis. One of the rarer CRC metastases is bone metastasis, especially pelvic metastasis, with minor symptoms that frequently overlap with other degenerative diseases. The 85-year-old woman with CRC experienced progressive lower back pain radiating to both legs. CT scan showed degenerative spine disease. Further bone scan revealed lytic lesions on the superior pubic ramus, prompting a rare diagnosis of pelvic metastasis in CRC. The clinical symptoms exhibited by a late-onset CRC patient, consisting of lower back pain radiating to both legs, accidentally concealed the rare presence of pelvic metastasis. In this case, the bone metastasis was successfully diagnosed following a routine bone survey, underscoring the importance of this procedure. Delayed diagnosis plummets the median survival from 20-30 months to just 2-3 months; clinicians must be aware of minor skeletal symptoms and utilize early advanced imaging to avoid catastrophic diagnostic delays and poor treatment outcomes. This rare case of pelvic metastasis in a CRC patient highlights the importance of not undermining minor skeletal symptoms in CRC patients and thoroughly exploring the possible cause of symptoms to avoid underdiagnosis or delays in diagnosing rare metastasis that could potentially alter outcomes for the worse.