RESUMO
BACKGROUND: Tailgut cyst is a congenital enterogenous cyst that rarely undergoes malignant transformation. Its clinical manifestations mainly correlate to the mass effect caused by the development of cysts and the infections that originate from these. Furthermore, the complete resection of this cyst is curative. We report our diagnostic and treatment experience with one case of malignant transformation of a perianal tailgut cyst, which was initially misdiagnosed as perianal abscess. CASE SUMMARY: A 72-year-old woman visited our institution with complaints of a refractory nonhealing lesion on the right hip, which repeatedly broke and suppurated for more than 70 years, and aggravated in 4 mo. The patient was given a diagnosis of refractory perianal abscess with repeated incision and drainage procedures. Computed tomography of the pelvic cavity revealed a giant perianal cyst. Subsequent biopsy revealed a tumor with moderate-to-severe glandular epithelial dysplasia, and suggested that this was derived from the developmental cysts in the posterior rectal space. After further clarifying the nature and extent of the tumor by magnetic resonance imaging, total cystic resection was performed. Postoperative histopathological examination confirmed the malignancy, dictating the investigators to add postoperative chemotherapy to the treatment regimen. CONCLUSION: The malignant transformation of perianal tailgut cysts is very uncommon, and this should be differentiated from perianal abscess. Complete surgical removal is curative, and postoperative pathology may determine the necessity of additional postoperative chemotherapy or radiotherapy, which may be beneficial for preventing local recurrence and metastasis.
RESUMO
BACKGROUND: Distant metastasis of colorectal cancer to the anus is very rare, with only 30 related cases published in PubMed thus far. Therefore, recurrence of colorectal cancer derived anus metastases is rarely seen and less presented. CASE SUMMARY: Here we report an 80-year-old male patient who underwent radical resection for sigmoid colon cancer in January 2010 and another surgery for anal fistula resection in December 2010. Postoperative pathology of the anal fistula revealed a metastatic moderately differentiated adenocarcinoma. The patient subsequently received chemotherapy and radiotherapy. In May 2020, after the patient reported symptoms of anal swelling and pain, computed tomography and magnetic resonance imaging revealed a perianal abscess. Perianal mass biopsy was performed, and the postoperative pathological diagnosis was metastatic moderately differentiated adenocarcinoma. CONCLUSION: This case highlights that there is a risk of recurrence of anal metastasis of colorectal cancer even after 10 years of follow-up. We also reviewed the literature and discuss potential mechanisms for anal metastasis of colorectal cancer, thus providing some suggestions for treatment of these cases.
RESUMO
Long chain acyl-CoA synthetase 1 (ACSL1), a key regulatory enzyme of fatty acid metabolism, catalyzes the conversion of long-chain fatty acids to acyl-coenzyme A. The full-length cDNAs of ACSL1a and ACSL1b were cloned from the liver of a grass carp. Both cDNAs contained a 2094bp open reading frame encoding 697 amino acids. Amino acid sequence alignment showed that ACSL1a shared 73.5% sequence identity with ACSL1b. Each of the two ACSL1s proteins had a transmembrane domain, a P-loop domain, and L-, A-, and G-motifs, which were relatively conserved in comparison to other vertebrates. Relative expression profile of ACSL1 mRNAs in different tissues indicated that ACSL1a is highly expressed in heart, mesenteric adipose, and brain tissues, whereas ACSL1b is highly expressed in heart, white muscle, foregut, and liver tissues. Nutrient regulation research showed that the expression levels of ACSL1a and ACSL1b were significantly down-regulated when 3, 6, and 9% fish oil were added in diet of grass carp as compared to the control group. However, no significant difference in the levels of ACSL1 mRNA was observed between the experimental groups. This study demonstrated the relationship between ACSL1a and ACSL1b genes in grass carp and laid a foundation for further research on ACSL family members in other species.