CASE 11577 Published on 27.02.2014

Kallmann syndrome

Section

Uroradiology & genital male imaging

Case Type

Clinical Cases

Authors

Francisco Rego Costa, Teresa Fernandes, Elisabete Rios, Bárbara Viamonte

Hospital de São João,
Porto, Portugal;
Email:franciscoregocosta@gmail.com
Patient

50 years, male

Categories
Area of Interest Genital / Reproductive system male, Pelvis ; Imaging Technique CT
Clinical History
A 50-year-old male farmer came to the emergency department complaining of lower abdominal pain and abdominal distension for two months. He had worsening of symptoms in the previous week. He had a medical history of delayed puberty onset.
Imaging Findings
Plain film of the abdomen showed no signs of bowel obstruction such as bowel distension or air-fluid levels.
CT of the abdomen and pelvis revealed a well-circumscribed solid pelvic mass measuring 12 x 12 x 9 cm, located anterior superiorly and slightly to the right of the bladder. The lesion showed heterogeneous contrast enhancement and internal areas of low-attenuation, consistent with necrosis.
Para-aortic and iliac lymphadenopathy were also seen.
No ascites or parenchymal lesions were detected.
In addition, the scrotal sac was empty and a nodular soft tissue mass suggestive of an ectopic testicle was identified in the left aspect of the pelvis. Given these findings, a neoplasm of the right ectopic testicle was the most probable diagnosis.
Discussion
Kallmann syndrome is a form of hypogonadotropic hypogonadism. In contrast to what happens in the idiopathic form of hypogonadotropic hypogonadism, patients with this syndrome present with anosmia or severe hyposmia in addition to the gonadotropin-releasing hormone deficiency.
This is a rare disorder with an estimated male prevalence varying from 1 in 10, 000 to 1 in 86, 000, according to different studies.
Some of the genes involved in the pathogenesis of this syndrome have been identified, the most important one being the KAL 1 gene. When mutant, this gene leads to gonadotropin-releasing hormone deficiency and anosmia due to abnormalities of neuronal migration.

In our case, the patient presented with the classic clinical picture of Kallmann syndrome during puberty but was not diagnosed until the age of 50.

As a child he was brought to medical attention by his parents due to abnormal physical development, but was eventually lost to follow-up.

At physical examination, absence of secondary sex characteristics was notorious including the absence of facial hair, decreased body hair, a high-pitched voice and a small penis. Cryptorchidism was present, which only happens in a minority of these patients.
Severe hyposmia was also diagnosed after proper testing.
The detection of a pelvic mass in this patient led to a better work-up on his clinical history which eventually allowed the diagnosis of Kallmann syndrome.

Imaging findings in our case were straightforward. CT images revealed a large heterogeneous solid pelvic mass. The size of the mass and the presence of retroperitoneal adenopathy were suggestive of a malignancy.
The evidence of an empty scrotal sac, the detection of a probable ectopic contralateral testicle and the distribution of adenopathies allowed a presumptive diagnosis of a testicular malignancy.
An excisional biopsy was performed, confirming the diagnosis of a seminoma. In these patients orchiectomy of the contralateral ectopic testicle is advised.

This case stresses the importance of the clinical history in establishing a proper diagnosis. The differential diagnosis of a pelvic mass and retroperitoneal adenopathy in a middle age patient is broad. However, given the clinical picture and empty scrotal sac, the diagnosis of a malignant neoplasm of an ectopic testicle was almost obvious.
Differential Diagnosis List
Metastatic testicular seminoma in a patient with Kallmann syndrome.
Seminoma
Non-seminomatous germ cell tumours
Testicular lymphoma (due to the presence of para-aortic lymphadenopathy)
Other uncommon causes to consider are sex cord-stromal tumours and testicular metastases.
Final Diagnosis
Metastatic testicular seminoma in a patient with Kallmann syndrome.
Case information
URL: https://www.eurorad.org/case/11577
DOI: 10.1594/EURORAD/CASE.11577
ISSN: 1563-4086