• Journal of Korean Neurosurgical Society
• /
• v.64 no.3
• /
• pp.386-405
• /
• 2021

Recent advancements in basic research on the process of secondary neurulation and increased clinical experience with caudal spinal anomalies with associated abnormalities in the surrounding and distal structures shed light on further understanding of the pathoembryogenesis of the lesions and led to the new classification of these dysraphic entities. We summarized the changing concepts of lesions developed from the disordered secondary neurulation shown during the last decade. In addition, we suggested our new pathoembryogenetic explanations for a few entities based on the literature and the data from our previous animal research. Disordered secondary neurulation at each phase of development may cause corresponding lesions, such as failed junction with the primary neural tube (junctional neural tube defect and segmental spinal dysgenesis), dysgenesis or duplication of the caudal cell mass associated with disturbed activity of caudal mesenchymal tissue (caudal agenesis and caudal duplication syndrome), failed ingression of the primitive streak to the caudal cell mass (myelomeningocele), focal limited dorsal neuro-cutaneous nondisjunction (limited dorsal myeloschisis and congenital dermal sinus), neuro-mesenchymal adhesion (lumbosacral lipomatous malformation), and regression failure spectrum of the medullary cord (thickened filum and filar cyst, low-lying conus, retained medullary cord, terminal myelocele and terminal myelocystocele). It seems that almost every anomalous entity of the primary neural tube may occur in the area of secondary neurulation. Furthermore, the close association with the activity of caudal mesenchymal tissue in secondary neurulation involves a wider range of surrounding structures than in primary neurulation. Although the majority of the data are from animals, not from humans and many theories are still conjectural, these changing concepts of normal and disordered secondary neurulation will provoke further advancements in our management strategies as well as in the pathoembryogenetic understanding of anomalous lesions in this area.

• Journal of Veterinary Clinics
• /
• v.26 no.4
• /
• pp.386-390
• /
• 2009

A 10-year-old female collared peccary (Tayassu tajacu) was referred due to a large palpable mass in caudal abdomen. Physical examination revealed a firm and freely moveable mass (15 ${\times}$ 9 cm) in the right side of caudal abdomen. Thoracic radiographic findings revealed a few well circumscribed nodules. This case was diagnosed as mammary gland squamous cell carcinoma with pulmonary metastasis based on histopathological and immunohistochemical findings. This type of mammary gland tumors is uncommon in wild animals. The patient survived for one month after the diagnosis. This is the first case report of mammary squamous cell carcinoma in a collard peccary and the second case report of metastatic carcinoma to lung in a collared peccary.

• Journal of Veterinary Clinics
• /
• v.22 no.2
• /
• pp.148-152
• /
• 2005

An intact female, 5-year-old, Pekingese, weighing 3.5kg with a history of a palpated abdominal mass was referred to Veterinary Medical Teaching Hospital, Seoul National University. In laboratory examination, there were no remarkable abnormalities. Radiographic findings included a left mid-abdominal mass with ill-defined margin, serosal detail loss of peritoneal space, non-uniform opacity of retroperitoneal space, and a radiopaque cystic calculus. On abdominal ultrasonography, a heterogeneous parenchymal mass with irregular contour in the left renal region was found. Computed tomographic findings showed a tumor embolus within the caudal vena cava and an invasion into mesentery, small bowel loops, spleen and pancreas around the large left renal mass. Unilateral nephroureterectomy was performed. Histopathologic examination of the resected mass confirmed the diagnosis of renal cell carcinoma. The dog died one day after surgery. Although ultrasonography could give diagnostic information about mass characteristics, computed tomography (CT) can provide key imaging features of mass characteristics.

• Journal of Veterinary Clinics
• /
• v.32 no.3
• /
• pp.247-250
• /
• 2015

A 10-year-old spayed female Pomeranian dog weighing 3.65 kg was presented with a 7-month history of urinary incontinence, stranguria and hematuria. The patient had mass lesions at left prescapular region ($3cm{\times}3cm$) and left axillary region ($5cm{\times}4cm$). Diagnosis of transitional cell carcinoma (TCC) with multiple cutaneous metastasis was made. Dog was treated with chemotherapy using mitoxantrone and piroxicam for 5 months. Although TCC size of urinary bladder was decreased during chemotherapy, there was no change of subcutaneous tumor size and mild relief of clinical signs. Partial anorexia for 3 weeks and multiple masses were noted at left caudal abdominal wall and left medial thigh (203 days after first presentation) and assessed as chronic kidney disease and additional subcutaneous metastasis of urinary bladder TCC by post-mortem and histopathological findings.