Inguinoscrotal lymphatic reflux detected by lymphoscintigraphy

Lymphoscintigraphy for Imaging of the Lymphatic Flow Disorders

Lymphoscintigraphy has introduced with the great advantage for diagnostic imaging of the lymphatic flow disorders. Lymphoscintigraphy can be performed in patients of any age, including neonates, and even in patient in critical conditions. The procedure is quite simple, and it needs only subcutaneous injection of small amounts of radiotracers. From subcutaneous tissue the radiotracer is taken by the lymphatic vessels and gives off energy in the form of gamma radiation detected by a gamma camera. Radiotracers rarely cause the allergic reaction and can be administered to the patients with allergy to iodine contrast media. Comparing with the Lipiodol, radiotracers cannot cause pulmonary embolism; therefore, it is safe for the patients with respiratory dysfunction. The objective of this article is to describe the indication, technique, equipment, pitfalls, safety, and effectiveness of lymphoscintigraphy for imaging of the lymphatic flow disorders.

Bilateral axillary lymph node uptake of radiotracer during lower extremity and scrotal lymphoscintigraphy in a case of primary scrotal lymphoedema

Lymphoscintigraphy is a useful technique for the evaluation of lymphatic function in the presence of limb swelling. The authors report a case where genital swelling in a 20-year-old man was investigated by lymphoscintigraphy. We performed lower limb lymphoscintigraphy and scrotal lymphoscintigraphy in the patient on two different days. Lower limb revealed dermal backflow pattern in lower limbs, inguinoscrotal reflux of the lymph and unexpected avid radiotracer uptake in the axillae bilaterally. Scrotal lymphoscintigraphy revealed slow movement of the lymph from the scrotal skin and again unexpected avid radiotracer uptake in the axillae bilaterally. Findings were concluded as congenital hypoplasia of lymphatics in lower limbs, congenital lymphectasia/compensatory megalymphatics in scrotum and aberrant lymphatic pathway, possibly due to malfunctioning/nonfunctioning thoracic duct.

Significance of increased scrotal Tc-99m MDP uptake in patients with prostate cancer

OBJECTIVE

We observed an unusually increased scrotal uptake as an interesting finding in some patients with prostate cancer who were scanned for any possible metastatic disease. This study was designed to investigate the significance of this incidental finding in the technetium-99m methylene diphosphonate scintigraphies.

METHODS

The study population consisted of 104 patients with biopsy-proven prostate cancer (group I), 55 male patients with other cancers (group II), 30 male patients with nonmalignant diseases (group III) and finally 15 patients with benign prostate hypertrophy (group IV). The square-shaped regions of interest are placed centrally on the scrotum and then on the lateral femoral soft tissue. Then the simple ratios of the scrotal and femoral soft tissue mean counts (S/Bg) were calculated. The statistical significance of differences among the groups in terms of scrotal uptake was determined.

RESULTS

Group I showed increased scrotal uptake relative to the other groups. The mean uptake ratios (S/Bg±standard deviation) were 3.49±1.42 in group I, 2.89±0.70 in group II, 2.87±0.75 in group III, and 2.91±0.60 in group IV. This ratio was significantly higher in patients with prostate cancer than the normal group (P=0.024), the group with benign prostate hypertrophy (P=0.004), and the patients with other cancers (P=0.004).

CONCLUSION

Our results showed that technetium-99m methylene diphosphonate bone scintigraphy, as a routine for detecting metastatic disease or performed for other purposes, could give clues for a hidden prostate cancer. Then, in elderly male patients, we strongly recommend that it is wise to keep one's eye on scrotal activity when bone scans are read and where there is any doubt, take appropriate regions of interest to make quantitative evaluations.

Intradermal lymphoscintigraphy at rest and after exercise: a new technique for the functional assessment of the lymphatic system in patients with lymphoedema

AIM

The aim of this study was to evaluate the effect of implementing a new technique, intradermal injection lymphoscintigraphy, at rest and after muscular exercise on the functional assessment of the lymphatic system in a group of patients with delayed or absent lymph drainage.

METHODS

We selected 44 patients (32 women and 12 men; 15 of 44 with upper limb and 29 of 44 with lower limb lymphoedema). Thirty of 44 patients had bilateral limb lymphoedema and 14 of 44 had unilateral disease; 14 contralateral normal limbs were used as controls. Twenty-three patients had secondary lymphoedema after lymphadenectomy and the remaining 21 had idiopathic lymphoedema. Each of the 44 patients was injected with 50 MBq (0.3-0.4 ml) of (99m)Tc-albumin-nanocolloid, which was administered intradermally at the first interdigital space of the affected limb. Two planar static scans were performed using a low-energy general-purpose collimator (acquisition matrix 128 x 128, anterior and posterior views for 5 min), and in which drainage was slow or absent, patients were asked to walk or exercise for 2 min. A postexercise scan was then performed to monitor and record the tracer pathway and the tracer appearance time (TAT) in the inguinal or axillary lymph nodes.

RESULTS

The postexercise scans showed that (i) 21 limbs (15 lower and six upper limbs) had accelerated tracer drainage and tracer uptake in the inguinal and/or axillary lymph nodes. Two-thirds of these showed lymph stagnation points; (ii) 27 limbs had collateral lymph drainage pathways; (iii) in 11 limbs, there was lymph drainage into the deeper lymphatic channels, with unusual uptake in the popliteal or antecubital lymph nodes; (iv) six limbs had dermal backflow; (v) three limbs did not show lymph drainage (TAT=not applicable). TAT=15 + or - 3 min, ranging from 12 to 32 min in limbs with lymphoedema versus 5 + or - 2 min, ranging from 1 to 12 min in the contralateral normal limbs (P<0.001).

CONCLUSION

Intradermal injection lymphoscintigraphy gives a better imaging of the lymph drainage pathways in a shorter time, including cases with advanced lymphoedema. In some patients with lymphoedema, a 2-min exercise can accelerate tracer drainage, showing several compensatory mechanisms of lymph drainage. The effect of the exercise technique on TAT and lymphoscintigraphy findings could result in a more accurate functional assessment of lymphoedema patients.

Pancreatic cancer with chylous ascites demonstrated by lymphoscintigraphy: successful treatment with peritoneovenous shunting

A 60-year-old woman was admitted to our hospital because of abdominal distension caused by massive chylous ascites. Six months earlier, she was diagnosed with inoperative pancreatic head cancer and biliary tract stenting and radiation therapy were performed due to obstructive jaundice. The chylous ascites was observed by lymphoscintigraphy with 99mTc-labeled human serum albumin. It showed upper abdomen accumulation and leakage into the abdominal cavity, and a diagnosis of chylous ascites caused by obstruction or rupture of lymphocele due to pancreatic cancer was made. Chylous ascites did not improve with a conservative therapy, including low-fat diet and administration of flousemide, but was successfully treated with a peritoneovenous shunt using a Denver shunting tube. In association with the placement of the shunt, she lived for 15 months after the first diagnose of pancreatic cancer without pancreatoduodenectomy.