Baseline 18F-FDG PET/CT quantitative parameters as prognostic factors in esophageal squamous cell cancer

AIM

To determine the utility of [¹⁸F]FDG PET/CT quantitative parameters as prognostic factors for the response to neoadjuvant treatment, progression-free survival (PFS) and cancer-specific survival (CSS) in patients with esophageal squamous cell carcinoma (SCC).

MATERIAL AND METHODS

Thirty patients (29 men) diagnosed with SCC were retrospectively evaluated over a 6-year interval. Metabolic parameters were determined: maximum SUV (SUVmax), mean SUV (SUVmed), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) from baseline PET/CT study. After treatment with chemotherapy and/or radiotherapy, response to treatment and patient survival were assessed. The comparison of parameters between groups of responders and non-responders was carried out using a Mann-Whitney U test ROC curves and the Kaplan-Meier method were used for analysis of prognostic factors and survival curves.

RESULTS

The average follow-up was 22.4 months, with 22 recurrence-progressions and 25 deaths. Significant differences were demonstrated between responders and non-responders with respect to tumor size, MTV and TLG. Survival analysis found significant differences for SCE and CSS depending on these three parameters.

CONCLUSION

Metabolic parameters MTV and TLG, and tumor size were prognostic factors for neoadjuvant treatment response, PFS, and CSS in patients diagnosed with SCC. Neither SUVmax nor SUVmed were predictive for any of the evaluation criteria. Results could help to personalize patient treatment.

Baseline 18F-FDG PET/CT quantitative parameters as prognostic factors in esophageal squamous cell cancer

AIM

To determine the utility of 18F-FDG PET/CT quantitative parameters as prognostic factors for the response to neoadjuvant treatment, progression-free survival (PFS) and cancer-specific survival (CSS) in patients with esophageal squamous cell carcinoma (SCC).

MATERIAL AND METHODS

Thirty patients (29 men) diagnosed with SCC were retrospectively evaluated over a 6-year interval. Metabolic parameters were determined: maximum SUV (SUVmax), mean SUV (SUVmed), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) from baseline PET/CT study. After treatment with chemotherapy and/or radiotherapy, response to treatment and patient survival were assessed. The comparison of parameters between groups of responders and non-responders was carried out using a Mann-Whitney U test. ROC curves and the Kaplan-Meier method were used for analysis of prognostic factors and survival curves.

RESULTS

The average follow-up was 22.4months, with 22 recurrence-progressions and 25 deads. Significant differences were demonstrated between responders and non-responders with respect to tumor size, MTV and TLG. Survival analysis found significant differences for SCE and CSS depending on these three parameters.

CONCLUSION

Metabolic parameters MTV and TLG, and tumor size were prognostic factors for neoadjuvant treatment response, PFS, and CSS in patients diagnosed with SCC. Neither SUVmax nor SUVmed were predictive for any of the evaluation criteria. Results could help to personalize patient treatment.

18F-FDG PET/CT quantitative parameters as prognostic factor in localized and inoperable lung cancer

AIM

To assess the utility of ¹⁸F-FDG PET/CT quantitative parameters as prognostic factor in patients diagnosed with localized and inoperable lung cancer treated by stereotactic body radiotherapy (SBRT).

MATERIAL AND METHODS

Fifty patients (42 men) diagnosed in the last 7years with early-stage lung cancer and treated with SBRT alone were assessed by a prospective study. After PET/CT study, metabolic parameters maximum SUV (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) were determined at different thresholds. The prognostic factors for overall survival (OS), cause-specific survival (CS) and disease-free survival (DFS) were analysed by Cox proportional hazards model and the survival analysis by Kaplan-Meier method.

RESULTS

The average follow-up was 39.6months, with 21 recurrences and 24 dead. Univariate analysis determined MTV₃₀ and MTV₄₀ as predictors for OS; MTV₃₀, MTV₄₀, TLG₃₀ and TLG₄₀ for CS, and MTV₂, MTV₃₀, MTV₄₀, TLG₂, TLG₃₀ and TLG₄₀ for DFS. Survival analysis found statistically significant differences for CS and DFS depending on tumor size and for DFS considering the cut-off values of MTV₂ and TLG₂ (threshold SUVmax=2). SUVmax, age and sex were not shown to be significant factors.

CONCLUSION

Pre-treatment quantitative assessment using metabolic parameters MTV₂ and TLG₂ as well as tumor size proved to be prognostic factors in patients diagnosed with localized and inoperable lung cancer treated by SBRT. Results could help to personalize treatment.

Uncommon isolated distant subcutaneous tissue and skeletal muscle metastasis from oesophageal cancer diagnosed by PET/CT (18)F-FDG

Distant soft-tissue metastases (subcutaneous tissues and skeletal muscle) are extremely rare, particularly in oesophageal carcinoma. The case is described of a patient who was treated for oesophageal adenocarcinoma 2.5 years previously. A PET/CT was performed showing metastatic spread due to a solitary focus of increased tracer uptake corresponding to one subcutaneous node in the upper abdomen. An excisional biopsy showed a metastasis from the carcinoma. Restaging PET/CT (18)F-FDG study was performed 2 year later, demonstrating foci of increased uptake within several muscles as isolated distant haematogenous spread of metastases, histopathologically confirmed. As most of soft-tissue metastases are asymptomatic, the physicians should recommend a histopathological study of focal FDG uptake at subcutaneous tissues and/or skeletal muscles, because they may be the first sign of disease spread, so therapeutic management of these patients could be changed.

[Use of radioguided surgery in the surgical treatment of osteoid osteoma]

OBJECTIVE

Osteoid osteoma is the third most common benign bone tumor and complete surgical resection is definitive treatment. There are a limited number of publications on the use of radioguided surgery in this type of lesion. To assess the utility of radioguided surgery in our environment as a method of surgical treatment of this tumor.

MATERIAL AND METHODS

We retrospectively evaluated 12 patients (2 women and 10 men, age range 9-44 years) with clinical and radiological suspicion of osteoid osteoma. Bone scintigraphy showed foci of pathology uptake compatible with suspected lesion in the femur (4 cases), tibia (3), vertebral column (3), humerus (1) and talus (1). Subsequently patients underwent surgical treatment by radioguided surgery after injection of a dose of (99m)Tc-hydroxy diphosphonate. The nidus was removed using gamma probe and mini gamma camera, considering the technique to be completed when its counts decreased to the levels of the surrounding bone counts.

RESULTS

Lesions were located in all patients (12 of 12), and were confirmed histologically in 8 of them, including an osteoblastoma. The cure rate was 100%, based on the disappearance of pain after a minimum follow-up of 6 months.

CONCLUSION

Use of radioguided surgery in the surgical treatment of osteoid osteoma showed satisfactory results, with 100% efficiency in both lesion location and outcome of treatment and without major postoperative complications.

[Clinical application of ROLL technique in non-breast diseases. Complementary use after PET-CT study]

OBJECTIVE

The aim of this study was to evaluate the usefulness of ROLL technique (Radioguided Occult Lesion Localization) as a verification method of suspicious lesions not related to breast disease found in PET-CT studies.

MATERIAL AND METHODS

We retrospectively evaluated 9 patients diagnosed of cancer or with suspected tumor disease who showed hypermetabolic lymph nodes in (18)F-FDG PET-CT. Subjects underwent diagnostic testing for evaluation of treatment response in lymphoma (3), suspected recurrence in other tumors (3) or biopsy guide (3). The study group consisted of 4 women and 5 men, age range 25-72 years. ROLL technique was performed in surgically accessible lesions (supraclavicular region, lateral cervical, axillary and inguinal) with an intralesional injection of (99m)Tc-albumin macroaggregates guided by ultrasound the day before surgery. A scintigraphic study confirmed the focal tracer deposit and absence of skin contamination. During surgery, a gamma probe and portable gammacamera were used to locate lymph nodes.

RESULTS

Surgical localization of radiolabeled lymph nodes was achieved in all cases with minimally invasive surgery and few postoperative complications. Histological study resulted in five tumor involvement (3 lymphoma, 1 germ cell tumor and 1 neuroendocrine carcinoma) and confirmed the existence of four false-positives in PET-CT study (1 sarcoidosis and 3 reactive follicular hyperplasia).

CONCLUSION

The ROLL technique proved to be a useful and relatively simple method for the study of no breast lesions suspicious of malignancy in PET-CT study.

The usefulness of densitometry as a method of assessing the nutritional status of athletes. Comparison with body mass index

The body mass index (BMI) is used to assess nutritional status. The result in athletes may be overestimated due to increase in muscle mass.

OBJECTIVE

To assess the usefulness of fat mass index (FMI) and lean mass index (LMI) determination as indicators of nutritional status and to compare the results with BMI.

MATERIAL AND METHODS

We studied 28 amateur rugby players, male. After being subjected to whole body densitometry by dual X-ray absorptiometry, we determined fat and lean body mass together with other parameters. FMI (fat in kg/height in meters(2)), LMI (lean in kg/height in meters(2)) and appendicular muscle mass index (AMMI, arms and legs musculature in kg/height in meters(2)) were calculated.

RESULTS

Using BMI, 18 players were overweight and 4 obese type I. Considering FMI, 7 of them had normal values and high LMI and AMMI, one of them changed from overweight to obese and another one from obese to overweight. Of the 6 players with normal BMI, one of them showed fat excess and another one fat defect. The results changed the assessment of nutritional status in 39% of players.

CONCLUSIONS

Although BMI is an appropriate parameter in general population for the assessment of nutritional status, in athletes should be taken into account fat and muscle body percentage and their corresponding indexes. The whole body densitometry appears to be a simple and reliable technique for this purpose.

Lymphoscintigraphy for differential diagnosis of peripheral edema: diagnostic yield of different scintigraphic patterns

Edema of the limbs is a common reason for medical consultation, for which the lymphoscintigraphy is considered to be a reliable method for its differential diagnosis.

OBJECTIVE

To evaluate the usefulness of radionuclide studies in the differential diagnosis of edema, and the diagnostic yield of different scintigraphic patterns.

MATERIAL AND METHODS

A total of 61 patients, mean age 43 years, referred to our Department in the last three years for suspected lymphoedema, were considered. One patient was discarded due to lack of diagnosis, 56 had lower limb edema and 4 upper limb edema. After intradermal injection of two doses of (99m)Tc-nanocolloid, scintigraphic scans were made at 30 and 120minutes. The final diagnosis was based on imaging tests, clinical course, and response to treatment. We calculated the parameters of the diagnostic yield of four different scintigraphic patterns (presence of dermal backflow, asymmetry-alteration in inguinal/axillary nodes, presence of collateral pathways, and visualization of intermediate lymph nodes), considering them individually and jointly.

RESULTS

The best diagnostic yield was achieved by considering dermal backflow and asymmetry in inguinal/axillary nodes (accuracy 88.9%, specificity 96.4%, PPV 95.5%). Evaluation of intermediate lymph nodes and presence of collateral pathways contributed little to the diagnostic yield, showing poor sensitivity and high false positive rates.

CONCLUSION

The lymphoscintigraphy had high diagnostic yield, allowing early treatment of lymphœdema. The dermal backflow and asymmetry in inguinal/axillary nodes had the greatest diagnostic accuracy. Evaluation of intermediate lymph nodes and visualization of collateral pathways contributed little to improving the diagnosis.

SPECT-CT with 67Ga-citrate in the management of spondylodiscitis

Spondylodiscitis affects a small proportion of all patients with locomotor system infections, however its early diagnosis is important due to its potential morbidity. Magnetic resonance imaging is the diagnostic method of choice. Nonetheless, it has certain limitations and is not suitable for all patients. The conventional scintigraphic studies for evaluating spondylodiscitis are those performed with (99m)Tc-HDP and (67)Ga-citrate. However, their poor image resolution is a disadvantage of these techniques. The use of hybrid Single Photon Emission Computed Tomography-Computed Tomography (SPECT-CT) improves detection of the disease by combining functional and anatomical images. We present 9 patients with suspicion of spondylodiscitis who underwent sequential bone scintigraphy with (99m)Tc-HDP and SPECT-CT with (67)Ga-citrate, with positive findings confirmed by clinical monitoring for at least 6 months.

[Neurolymphomatosis: diagnosis of extension and assessment of response to treatment with PET-CT]

Neurolymphomatosis is a rare neurological manifestation of non-Hodgkin's lymphoma (NHL) and it may be its first and sole manifestation. Diagnosis is often difficult and nerve biopsy is generally required. However, this it is not always possible to perform or is not conclusive. We present the case of a 66-year-old woman diagnosed with giant B-cell NHL. After 6 cycles of chemotherapy, imaging and molecular biology techniques showed complete remission. At four months after treatment, the patient complained of low back pain of radicular distribution. CT and MRI imaging showed signs of lymphoproliferative activity of L5 and also lesions to thoracic nerve roots. A PET-CT was requested in order to complete the diagnosis and plan the treatment. Imaging confirmed the presence of tumor recurrence with neurolymphomatosis and also indicated lesions on the chest and abdominal level. Thus, it was decided to start a new line of chemotherapy, without performing the histological study through biopsy. This case illustrates the important role played by PET-CT imaging in neurolymphomatosis diagnosis. This technique can help the patient avoid more aggressive procedures, such as a biopsy, and can also be useful in the follow-up and assessment of the treatment response to NHL-diagnosed patients.

Neurocirugía radiodirigida: una aplicación novedosa de la Medicina Nuclear

Brain tumours show uptake with Thallium-201 Chloride with high target/background rate and they would benefit from radioguided surgery. We report a patient with a brain tumor that was Thallium positive in a brain SPECT. On the next day in the operating room we injected 50 MBq of Thallium-201. At 40 minutes we confirmed tumour uptake with a gamma-probe and with a biopsy sample. After brain tumor resection was completed by conventional method, we found pathologic activity in tumoral bed with the gamma probe, that showed persistence of increased activity. After a new evaluation, residual tumor tissue was located in the pathological uptake area and was removed. Control CT showed complete resection, although the Thallium SPECT carried out after surgery showed faint uptake in the anterior pole of the surgical bed. Radioguided surgery was evaluated as a useful and promising technique by the neurosurgeon.

[Verbal auditory agnosia: SPECT study of the brain]

Verbal auditory agnosia are rare in clinical practice. Clinically, it characterized by impairment of comprehension and repetition of speech but reading, writing, and spontaneous speech are preserved. So it is distinguished from generalized auditory agnosia by the preserved ability to recognize non verbal sounds. We present the clinical picture of a forty-years-old, right handed woman who developed verbal auditory agnosic after an bilateral temporal ischemic infarcts due to atrial fibrillation by dilated cardiomyopathie. Neurophysiological studies by pure tone threshold audiometry: brainstem auditory evoked potentials and cortical auditory evoked potentials showed sparing of peripheral hearing and intact auditory pathway in brainstem but impaired cortical responses. Cranial CT-SCAN revealed two large hypodenses area involving both cortico-subcortical temporal lobes. Cerebral SPECT using 99mTc-HMPAO as radiotracer showed hypoperfusion just posterior in both frontal lobes nect to Roland's fissure and at level of bitemporal lobes just anterior to Sylvian's fissure.

[Supracricoid laryngectomies with cricohyoidopexy. A clinical study of 6 cases]

A prospective study was carried out in 6 patients with cancer of larynx operated between 1986 and 1988. Technical aspects for supracricoid partial laryngectomy with cricohyoidopexy are described. Indications, follow-up and complications are discussed.

Serum TATI levels and clinical correlation in tumors of the head and neck

By radioimmunoassay (RIA) we studied tumor-associated trypsin inhibitor (TATI) in 152 serum samples, divided into three groups: 35 healthy subjects, used as controls; 25 individuals with benign pathology of the ear, nose and throat (ENT) region; 92 serial samples obtained from 69 patients with malignant disease of the head and neck. The malignant ENT group were classified in four stages according to the degree of tumor activity. The TATI concentrations (mean +/- SD) were as follows: control group, 16.0 +/- 3.4; benign group, 17.1 +/- 6.7; A0, 14.8 +/- 11.5; A1, 12.1 +/- 3.5; A2, 17.01 +/- 1.4; A3, 43.0 +/- 54.9.

[Epidural empyema; a complication of frontal sinusitis]

Two patients are presented with extradural empyema originating from the frontal sinus. The infection spread was in the first case via the diploic veins through the intact sinus wall, and in the second case after the destruction of the posterior wall of frontal sinus. The early diagnosis methods and surgical drainage are discussed. Braid scan and Computed tomography are the most useful methods for the evaluation of this pathology.