Conventionally fractionated radiation therapy is associated with long-term survival in dogs with infiltrative lipomas.

OBJECTIVE: To describe radiotherapy outcomes for canine infiltrative lipomas and provide detailed radiotherapy planning data. ANIMALS: 24 dogs from 2000 to 2020. METHODS: In this retrospective study, dogs received 1 to 3 surgeries prior to conventionally fractionated radiotherapy for gross (18) or microscopic (8) infiltrative lipomas. Dogs received 45 to 51 Gray (Gy) in 15 to 20 daily fractions, with 71% of dogs receiving 48 Gy in daily 3-Gy fractions. RESULTS: Masses were regionally located as follows: limbs (7), trunk (13), head/neck (4). At analysis, 16/24 dogs were deceased, 5/24 were alive (median follow-up for alive dogs: 1,216 days [range, 741 to 1,870 days]), and 3/24 were lost to follow-up. One living dog had progressive disease 923 days after completing conventionally fractionated radiotherapy and received another surgery. The estimated median overall survival (OS) after completing radiotherapy was 4.8 years (1,760 days; 95% CI, 1,215 to 2,777 days; range, 23 to 3,499 days) for any cause of death, and no patients were reported to have been euthanized or died from their tumor. No statistically significant difference was found for dogs based on gross versus microscopic disease (gross OS, 4.8 years vs microscopic OS, 3.6 years; P = .45). Furthermore, the number of surgeries before radiotherapy did not impact survival (P = .96). The survival difference between females (median OS, 7.6 years; 95% CI, 963 days to not reached) versus males (median OS, 4.6 years; 95% CI, 335 to 2,245 days; P = .05) was statistically significant, although 4/5 living dogs were female. CLINICAL RELEVANCE: This study demonstrates lengthy survivals with radiotherapy, even with gross disease, for dogs with infiltrative lipomas.

[Atypical Lipomatous Tumour of the Hand]. / Atypischer lipomatöser Tumor der Hand.

Atypical lipomatous tumours (ALT) are rare semi-malignant adipose tissue tumours with the potential to transform into sarcomas. They may occur throughout the body, although the hands are very rarely involved. We present the case of a 49-year-old man with a lipomatous tumour measuring 8×4 cm at the dorsum of the right thumb. MRI demonstrated an inhomogeneous signal after contrast medium application. The tumour was excised in its entirety. Since histology confirmed the diagnosis of an ALT, the thumb was irradiated. The patient remained free of recurrence. An ALT has to be suspected if a lipomatous tumour is very large. We recommend an MRI prior to surgery in tumours larger than 5 cm. Excision should follow oncologic principles.

[Multiple primary liponeurocytoma of the central nervous system].

We report a unique case of primary multiple liponeurocytoma. Liponeurocytoma is a rare benign tumor (Grade II) of the posterior cranial fossa with neural- or probably astrocytic-lineage cells; the tumor stroma contains mature adipocytes. This case is the thirty-eighth case of this pathology reported in the world literature and the first case of multiple form of this disease. We have provided a sufficiently thorough neuroradiological and histological picture that allows one to differentiate between a liponeurocytoma and other histological variants. Recommendations for the tactics for managing patients with this rare disease are proposed based on the analysis of treatment of this pathology reported in the world literature.

Three dosimetry models of lipoma arborescens treated by 90Y synovectomy.

PURPOSE: Lipoma arborescens (LA) is a benign intra-articular lipomatous proliferation of the synovial membrane. This extremely rare condition has previously been treated by intra-articular (90)Y radiosynoviorthesis but dosimetry literature on this form of radionuclide therapy is nonexistent. The authors detail methodology for successful treatment of LA and provide for the first time estimates of radiation dosimetry. The authors also analyze the biodistribution of the radiopharmaceutical over the course of the patient's treatment through sequential imaging. METHODS: A patient with bilateral LA underwent intracavity injection of (90)Y citrate colloid to the right and left knee joint spaces (181 and 198 MBq, respectively). SPECT/CT datasets were acquired over 9 days to quantify the biodistribution and kinetics of the radiopharmaceutical. Radiation dosimetry was performed using the MIRD schema (through OLINDA software), a custom voxel-based method, and a direct Monte Carlo calculation (OEDIPE). RESULTS: Follow-up MRI showed marked reduction in LA size in both knees. Mean absorbed doses to the LA were 21.2 ± 0.8 and 42.9 ± 2.3 Gy using OLINDA, 8.1 ± 0.3 and 16.7 ± 0.5 Gy using voxel based methodology, and 8.2 ± 0.3 and 15.7 ± 0.5 Gy for OEDIPE in the right and left LA, respectively. Distribution of the radiopharmaceutical within the joint space alters over the imaging period, with less than 1% of the remaining activity having moved posteriorly in the knee cavity. No uptake was detected outside of the joint space after assessment with whole-body scintigraphy. CONCLUSIONS: An activity of approximately 185 MBq successfully relieved clinical symptoms of LA. There was good correlation between direct Monte Carlo and voxel based techniques, but OLINDA was shown to overestimate the absorbed dose to the tumor. Accurate dosimetry may help select an activity more tailored to the specific size and location of the LA.

Hybrid myxoinflammatory fibroblastic sarcoma/hemosiderotic fibrolipomatous tumor: report of a case providing further evidence for a pathogenetic link.

Myxoinflammatory fibroblastic sarcoma and hemosiderotic fibrolipomatous tumor are rare, slow-growing soft tissue tumors of the distal extremities with recurrent potential. Recent cytogenetic studies have shown a t(1;10)(p22;q24) or der(10)t(1;10) in combination with aberrations of chromosome 3 in a limited number of cases of both entities. Here we report a case of a 42-year-old female with a soft tissue tumor of the ankle showing hybrid morphologic features of myxoinflammatory fibroblastic sarcoma and hemosiderotic fibrolipomatous tumor, a der(10)t(1;10), and abnormalities of chromosome 3. This hybrid lesion provides further evidence for a close relationship between these 2 tumor types.

Problematic differential diagnosis between cerebellar liponeurocytoma and anaplastic oligodendroglioma.

A cerebellar tumour, first diagnosed as an anaplastic oligodendroglioma, received radiation therapy (45 Gy) following gross total resection. The second histological study revealed a liponeurocytoma, a benign tumour not requiring adjuvant therapy. This case emphasizes the importance of considering this diagnosis to prevent unnecessary irradiation of such rumours.

Lipoma arborescens; successfully treated by yttrium-90 radiosynovectomy.

Although radiosynovectomy (RS) applications have been carried out for many years, clinical indications of this non-invasive procedure is thought to be limited probably due to the lack of information of clinicians. Clinicians' preferential indication for RS is the treatment-resistant synovitis of individual joints, i.e. despite systemic pharmacotherapy and intra-articular steroid injections. We present here a case of "lipoma arborescens" treated by yttrium-90, which is a rare intra-articular lesion characterized by villous proliferation of the synovial membrane and hyperplasia of subsynovial fat. The results of clinical, biochemical and hematological examinations, magnetic resonance (MR) imaging, arthroscopy and histological analysis have shown that the etiology was lipoma arborescens in a female patient, aged 36 having swelling and sometimes associating pain at her right knee for 4 years. We have applied to our patient's right knee RS with 185 MBq yttrium-90 colloid together with 40 mg of methylprednisolone acetate, although in our literature survey we have not met any similar case being treated with such indication. Even a year after the application, the patient has absolutely benefited from the treatment clinically, and this was also confirmed by comparative MR images (pre- and post-treatment). Consequently, we consider that Y-90 treatment might be applicable in suitable cases with lipoma arborescens.

[Experience of surgical treatment of the thymic gland tumors]. / Opyt khirurgicheskogo lecheniia opukholei vilochkovoi zhelezy.

The forty-years experience of treatment of 125 patients with thymic gland tumors was summarized, in 113 of them thymoma was revealed. In the disease of I-II stages the five-year survival index had constituted 75.6%, and in III-IV stages the method of choice is combined treatment, after which the five-years survival index does not exceed 31.2%. It is necessary to perform additional studying of factors, influencing the result of treatment of the thymic gland tumor.

Lymphangiolipoma of the lower extremity: 5-year radiological follow-up after radiotherapy treatment.

This report describes a lymphangiolipoma located in the extremity in a young woman. Radiotherapy effectively controlled recurrent lymphangiolipoma of the left upper leg that had been judged inoperable by limb-sparing surgical resection. In the case presented here, a dose of 50 Gy in 25 fractions over 5 weeks was employed without long-term complications after 5-year follow-up.

Results of irradiation of infiltrative lipoma in 13 dogs.

Thirteen dogs with infiltrative lipomas were treated with cobalt 60 radiation. Four of the thirteen dogs also received either whole body (n = 2) or combination local/whole body (n = 2) hyperthermia in conjunction with radiation therapy. Cytoreductive surgery was performed prior to radiation in 10 dogs, although only 3 dogs had microscopic disease at the time of radiation therapy. Dogs received a total dose of 45.6 Gy-63 Gy in 2.5-4 Gy/fraction on either a Monday/Wednesday/Friday schedule or on a daily Monday through Friday schedule. Twelve of the 13 dogs had computed tomography (CT) images acquired prior to irradiation. Survival time was determined from the time of completion of radiation therapy. Survival ranged from 6 months to 94 months, with a median (95% confidence interval) of 40 (18.5-77) months and a mean of 46.4 months. Only one dog was euthanized due to persistent signs related to the infiltrative lipoma at 6 months after the end of radiation therapy. There was no apparent difference in response based on whether or not the dogs received hyperthermia in conjunction with irradiation, although the numbers were too small to make any significant conclusions. It appears that dogs with infiltrative lipomas can benefit from external beam irradiation alone or in combination with surgery to effect long-term local tumor control.

Intradural tumors of the cauda equina: a single institution review of clinical characteristics.

A retrospective review of 106 cases of intradural tumors of the cauda equina are presented, subdivided into 5 groups according to their histological characteristics. For each group the clinical course and long-term postoperative results were analyzed: it emerged that differential diagnosis between neurinomas, meningiomas or non-tumoral lesions is not possible based on clinical findings alone and that neuroradiological diagnosis is more accurate when MRI is employed. Long-term prognosis was always favorable with the exception of the group of ependymomas. Nevertheless, early diagnosis in the latter group of tumors gives excellent results because prognosis is apparently directly correlated to the length of preoperative clinical history.