Lipoleiomyosarcoma of spermatic cord: an unusual presentation

Abstract

Spermatic cord malignancies are very rare tumours. Less than 100 cases of cord liposarcoma have been reported in the literature. Divergent differentiation into leiomyosarcoma and liposarcoma is a rare phenomenon but can occur. Lipoleiomyosarcoma usually represents the well-differentiated subtype of this entity. We report such a rare case in spermatic cord with an unusual presentation as a recurrent inguinal hernia in a 62-year-old man.

Background

Liposarcoma is a rare tumour of the spermatic cord and its differentiation into leiomyosarcoma is thus rarer. The most common differentiation is the dedifferentiated type, which is an aggressive cancer and the less common type is well differentiated with a better prognosis than the former. The well-differentiated type of liposarcoma with leiomyosarcoma is also known as lipoleiomyosarcoma. We report one such rare case with spermatic cord involvement.

Case presentation

A 62-year-old man presented with swelling in the right inguinal region for 1 year. The swelling was insidious in onset and gradually increasing. Initially, it was reducible but became irreducible for the last 6 months. On examination, a 6×6 cm(approx.) swelling was present at right inguinal region, extending up to root of scrotum. Swelling was doughy on palpation, not reducible and there was no cough impulse. A clinical diagnosis of incomplete, irreducible recurrent right inguinal hernia with content as omentum was made depending on history and clinical findings. Diagnosis was later confirmed with ultrasonography. There was a history of left inguinal hernia repair 10 years ago and right-sided hernioplasty 7 years ago.

Investigations

Complete blood count, erythrocyte sedimentation rate (ESR), liver and renal function tests were within normal limits. Ultrasonography suggested herniation of omentum into the right inguinal canal with extension up to the upper pole of right testis (figure 1). No bowel loops were seen.

Figure 1.

Ultrasonography showing herniation of omentum in the inguinal canal (arrow showing omentum in inguinal canal).

Treatment

The patient was planned for right inguinal hernioplasty under spinal anaesthesia. Intraoperatively, inguinal canal was occupied by a lipomatous soft-tissue structure of 7×6 cm (figure 2), which was densely adherent to the cord structures. The possibilities lipoma of the cord and retained omentum were considered, however, no sac was identified. Intense adhesions were noted in view of previous surgery. Cord structures were preserved and the soft-tissue was excised. Mesh of the previous surgery was incorporated in the inguinal canal wall by fibrosis, so it could not be retrieved separately. A 10×15 cm prolene mesh was placed and fixed. The patient had an uneventful postoperative course and was discharged on postoperative day 1, but on day 7, the patient presented with a fluctuant collection in the scrotum, diagnosed with seroma in the scrotal region with induration and redness in the right inguinal region. About 90 mL serous fluid was aspirated and the patient was asymptomatic subsequently.

Figure 2.

Excised specimen 7×6 cm (gross).

Microscopic examination revealed heterogeneous components of adipocytic admixed with smooth muscle tumour. Adipocytic component composed of mature-appearing adipocytic cells, univacuolated and multivacuolated lipoblasts, and myxoid areas containing atypical spindle cells. The smooth muscle component was intermixed as haphazardly arranged bundles (figure 3A–C). Proliferating thick and thin-walled blood vessels were seen. Adipocytic and lipoblastic cells were immunopositive with S100; while, smooth muscle component and some of spindle cells were positive with smooth muscle actin and desmin (figure 3D–F). The tumour cells were negative for HMB-45. A diagnosis of lipoleiomyosarcoma was made depending on the typical histopathological findings. Following a multidisciplinary meeting, adjuvant radiotherapy was given and the patient is under regular follow-up without any sign of recurrence for 4 months following surgical removal. A positron emission tomography-computed tomography (PET-CT) 2 months after surgery showed no metastasis or remnant tumour.

Figure 3.

Histopathology (A) H&E-stained sections show a tumour with components of adipocytic cells and smooth cells (A, HE; ×40). (B) The adipocytic area shows mature looking adipocytic cells, univacuolated and multivacuolated lipoblasts and atypical spindle cells (B, HE; ×400). (C) Smooth muscle cells are present in fascicular arrangement and bundles, and have hyperchromatic nuclei with bright eosinophilic cytoplasm (C, HE; ×400). (D) Lipoblasts are immunoreactive with S100 (D, ×400); (E) Smooth muscle tumour and spindle cells are positive for smooth muscle actin (E, ×400); (F) Smooth muscle tumour and spindle cells are positive for desmin (F, x400).

Outcome and follow-up

Following a multidisciplinary meeting, adjuvant radiotherapy was given and the patient is under regular follow-up without any sign of recurrence for 4 months following surgical removal. A PET-CT 2 months after surgery showed no metastasis or remnant tumour.

Discussion

Lesauvage described the first case of cord sarcoma in 1845.¹ Malignant tumour of the spermatic cord itself is a rare entity. Thus, liposarcoma of the cord is also rare and only 114 cases are described in the literature so far. These tumours should be differentiated from paratesticular tumours, which can be benign (lipoma, leiomyoma and haemangioma) or malignant (rhabdomyosarcoma, etc). Lipoma is the most common tumour of this group and it does not transform into sarcoma usually. Liposarcoma of the cord is usually asymptomatic and seen as a slow-growing painless tumour in sixth and seventh decade of life.^{2 3} Smooth muscle differentiation of these liposarcomas is seen sometimes. It is rare and less than 20 cases have been documented in literature according to our knowledge. This subtype of liposarcoma is of two types: (1) lipoleiomyosarcoma, also known as well-differentiated liposarcoma, having foci of relatively mature, but histologically atypical, smooth muscle tissue and (2) dedifferentiated liposarcoma with smooth muscle differentiation in the dedifferentiated areas.^4–8

Tumours containing adipocytes and smooth muscle differentiation have been well recognised for years in literature. One of the early described benign tumours is usually uterine or soft-tissue leiomyomas, which contain a variable amount of fat.⁹ Such lesions were called ‘lipoleiomyoma’ or ‘myolipoma’ depending on the preference of the authors. Smooth muscle in these tumours is devoid of nuclear atypia. Lipoleiomyosarcomas are rare tumours and was first described by Evans in 1990 when he reported three cases of well-differentiated liposarcoma with mature smooth muscle component and these smooth muscles seemed to blend with or even arise from the muscle wall of the vessels.⁶ Since then very few cases of similar tumours have been documented in the literature. They can occur anywhere like spermatic cord, abdomen, retroperitoneum and mediastinum. They tend to recur and multiple local recurrences have been seen. Though similar histology is seen in recurrences, rarely dedifferentiation has been documented in the literature for tumours arising from retroperitoneum.⁴

The second type of liposarcoma is dedifferentiated liposarcoma with areas of leiomyosarcoma in the dedifferentiated zones. Though small series and case reports are there, Henricks et al have the largest case series of dedifferentiated liposarcoma published so far (155 cases).⁵ It is somehow more common in incidence than its counterpart lipoleiomyosarcoma. In contrast to lipoleiomyosarcoma, dedifferentiated lipoleiomyosarcoma is a high-grade sarcoma with more frequent local recurrences seen following resection. A very high disease-related mortality rate has been documented in the literature.⁵

The behaviour of lipoleiomyosarcoma is essentially identical to well-differentiated liposarcoma without a smooth muscle component. However, lipoleiomyosarcomas seem to generate within body cavities usually, in comparison to ordinary well-differentiated liposarcomas, which occur more commonly in a peripheral location. They have almost similar risk of local recurrence. However, the major significance of lipoleiomyosarcoma is that the smooth muscle component may show evidence of dedifferentiation and, hence, it can have a more aggressive course in subsequent recurrence. So it is of great importance that these zones be recognised as showing smooth muscle differentiation. They have a distinct fascicular or packet-like arrangement, with a close resemblance of the cells to mature smooth muscle, and are associated with atypical mural changes within vessels.⁴

Though radical orchidectomy has been recommended for treatment of liposarcoma of cord,¹⁰ there is no standard treatment protocol described for lipoleiomyosarcomas in literature. It is mainly due to the fact that it is an extremely rare disease and it is difficult to come to a consensus on treatment with such small evidence. Until, only five cases of lipoleiomyosarcoma of cord have been documented in literature according to our knowledge (table 1). The largest case series on lipoleiomyosarcoma by Folpe and Weiss has shown that nuclear grade, margin status, adjuvant chemotherapy or radiotherapy, only follow-up has no effect on the recurrence of the tumour.⁴ Re-excision has been attempted in almost all cases of recurrence in literature. Prophylactic inguinal lymph node dissection is of doubtful benefit for liposarcoma and it had not been attempted in any of the cases of lipoleiomyosarcoma in literature so far. Though there is an incidence of recurrence after adjuvant radiotherapy, still postoperative radiotherapy is recommended for liposarcoma patients.¹⁰ In the series by Folpe and Weiss, recurrence has been seen in both the group of patients who have received radiotherapy and who have not, following surgery for lipoleiomyosarcoma. For our patient with lipoleiomyosarcoma, the multidisciplinary team had taken a decision of adjuvant radiotherapy. He is in on regular follow-up in follow-up-clinic and he has no sign of recurrence 3 months after surgery and completion of radiotherapy.

Table 1.

Reported cases of lipoleiomyosarcoma in literature

	Age/sex	Site	Surgery	Margin	Inguinal block dissection	Histology	Adjuvant therapy	Recurrence	Treatment for recurrence	Follow-up	Outcome
Evans6	49/male	Spermatic cord	−	Not available	−	Well diff	−	Nil	−	−	Alive
Suster et al 7	70/male	Spermatic Cord	High inguinal orchidectomy	Not available	Not done	Well diff	Ra	Nil	−	72 months	Alive
Folpe and Weiss4	65/male	Para-testicular	Local excision	+	Not done	Well diff	Not done	Yes (multiple)	Re-excision	96 months	Alive
Folpe and Weiss4	58/male	Spermatic cord	Local excision	+	Not done	Well diff	Not done	Yes (multiple)	Re-excision	132 months	Alive
Folpe and Weiss4	63/male	Spermatic cord	Local excision	+	Not done	Well diff	Not done	−	−	−	Alive

In conclusion, a high index of suspicion is needed for preoperative diagnosis of lipoleiomyosarcoma of cord. There is no established standard management protocol for lipoleiomyosarcoma of the spermatic cord. As the recurrence rate is high and it does not depend on margin status, histology or adjuvant therapy, surgical excision followed by radiotherapy and close follow-up may be done as an accepted treatment option for this disease.

Learning points.

• Spermatic cord tumours can be associated with and may present as an inguinal hernia. So a high index of suspicion is needed for preoperative diagnosis and planning for appropriate surgery.

• Histopathological examination should be performed for any abnormal tissue found during surgical procedure.

• There is no documented benefit from radical surgery, pelvic lymph node dissection or adjuvant therapy for patients with liposarcoma.

• Simple excision with radiotherapy and close follow-up may be equally effective as a treatment option for cord lipoleiomyosarcoma, as margin status does not alter recurrence rate of disease.

• Patients with lipoleiomyosarcoma need close follow-up, as chances of recurrence are high.