cow-2022-37

a) Teratoma

b) Gonadoblastoma

c) Dysgenetic testis

d) Meconium periorchitis

e) Scrotal calcinosis

1. d

Meconium periorchitis

This mass was identified during inguinal hernia repair by the general pediatric surgery team, and pediatric urologic surgery was consulted intraoperatively for guidance. The mass was distinct from the testis, which was mildly bruised but otherwise viable appearing. Grossly, the mass was received as a 1.5 cm aggregate of soft red-brown tissue. H&E-stained sections showed fragments of fibrous tissue and myxoid material with calcifications (Image 1, right side, and Image 2), thin delicate fibrous septations, abundant hemorrhage, green/yellow pigment-laden macrophages (Images 3 and 4), and focal hair shafts (Image 3, arrow). These collective findings are consistent with a benign, reactive mass-like formation rarely seen in infant males termed meconium periorchitis.

Meconium periorchitis results from extension of intra-abdominal meconium through a patent processus vaginalis. This lesion is usually found in association with meconium peritonitis due to a late gestation bowel abnormality, which causes spillage of contents into the peritoneal cavity. Meconium initiates an intense sterile foreign body reaction, which often results in peritoneal calcifications, as seen in this case (Image 5, abdominal CT, arrows).

This entity was first reported in 1953 in two patients with meconium peritonitis.1 However, many cases of meconium periorchitis are not associated with any known prenatal or perinatal abnormalities,2 and around half of patients present with asymptomatic scrotal swelling within the first 6 months of life.3 Occasionally, meconium periorchitis is diagnosed prenatally, and without surgical removal, masses have been reported to spontaneously resolve.1,3 Of note, an association with cystic fibrosis (CF) has been observed,4 though it appears that symptomatic meconium peritonitis is more likely to suggest CF than meconium periorchitis in isolation in an otherwise healthy male.3 Nonetheless, identifying meconium periorchitis should prompt the pathologist to suggest correlation with perinatal history and consideration for CF workup if other clinical features concerning for CF are present.

Histologically, the unique constellation of calcifications and evidence of meconium forming a mass in the paratesticular region raises few other entities in the pathologic differential diagnosis. Calcifying primary tumors of the testis in this age group include teratoma and gonadoblastoma, though meconium periorchitis is not associated with neoplasia. Torsion and hemorrhagic infarction can also result in testicular calcifications, though don’t typically result in a paratesticular mass lesion. In scrotal calcinosis, the lesions are typically confined to the cutaneous tissues and occur in older patients.

1. Olnick H and Hatcher H. Meconium peritonitis. J Am Med Assoc. 1953 Jun 13;152(7):582-4. PMID: 13044582

2. Dehner L, Scott D, Stocker J. Meconium periorchitis: a clinicopathologic study of four cases with a review of the literature. Hum Pathol. 1986 Aug;17(8):807-12. PMID: 3733069.

3. Jeanty C, Bircher A, Turner C. Prenatal diagnosis of meconium periorchitis and review of the literature. J Ultrasound Med. 2009 Dec;28(12):1729-34. PMID: 19933490.

4. Berdon W, Baker D, Becker J, De Sanctis P. Scrotal masses in healed meconium peritonitis. N Engl J Med. 1967 Sep 14;277(11):585-7. PMID: 6038621

Nabil Rahoui
PGY-3, Anatomic and Clinical Pathology
UNC Hospitals
Chapel Hill, NC

Steven Johnson
Assistant Professor
UNC School of Medicine, Department of Pathology and Laboratory Medicine
Chapel Hill, NC

Paratestis/scrotum

Calcifications, inguinal hernia, paratesticular mass, meconium periorchitis, scrotum