Correlation of 18F-FDG uptake on PET/CT with Ki67 immunohistochemistry in pre-treatment epithelial ovarian cancer. / Correlación de la captación de 18F-FDG de la PET/TC con el Ki67 de la inmunohistoquímica en el cáncer epitelial de ovario pretratamiento.

OBJECTIVE: Standardised uptake value (SUV) and volumetric parameters such as metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from 18F-FDG PET/CT are useful criteria for disease prognosis in pre-operative and post-treatment epithelial ovarian cancer (EOC). Ki67 is another prognostic biomarker in EOC, associated with tumour aggressiveness. The aim of this study is to evaluate the association between 18F-FDG PET/CT measurements and Ki67 in pre-treatment EOC to determine if PET/CT parameters could non-invasively predict tumour aggressiveness. MATERIAL AND METHODS: A pre-treatment PET/CT was performed on 18 patients with suspected or newly diagnosed EOC. Maximum SUV (SUVmax), mean SUV (SUVmean), whole-body MTV (wbMTV), and whole-body TLG (wbTLG) with a threshold of 30% and 40% of the SUVmax were obtained. Furthermore, Ki67 index (mean and hotspot) was estimated in tumour tissue specimens. Immunohistochemical findings were correlated with PET parameters. RESULTS: The mean age was 57.0 years old (standard deviation 13.6 years). A moderate correlation was observed between mean Ki67 index and SUVmax (r=0.392), SUVmean 30% (r=0.437), and SUVmean 40% (r=0.443), and also between hotspot Ki67 index and SUVmax (r=0.360), SUVmean 30% (r=0.362) and SUVmean 40% (r=0.319). There was a weaker correlation, which was inversely negative, between mean and hotspot Ki67 and volumetric PET parameters. However, no statistical significant differences were found for any correlations. CONCLUSIONS: SUVmax and SUVmean were moderately correlated with Ki67 index, whereas volumetric PET parameters overall, showed a weaker correlation. Thus, SUVmax and SUVmean could be used to assess tumour aggressiveness in pre-treatment EOC.

Dual time-point (18)F-FDG PET/CT to assess response to radiofrequency ablation of lung metastases.

AIM: To establish the usefulness of dual time-point PET/CT imaging in determining the response to radiofrequency ablation (RFA) of solitary lung metastases from gastrointestinal cancer. MATERIALS AND METHODS: This prospective study included 18 cases (3 female, 15 male, mean age 71±15 yrs) with solitary lung metastases from malignant digestive tract tumors candidates for RFA. PET/CT images 1h after injection of 4.07MBq/kg of (18)F-FDG (standard images) were performed at baseline, 1 month, and 3 months after RFA. PET/CT images 2h after injection centered in the thorax at 1 month after RFA were also performed (delayed images). A retention index (RI) of dual time-point images was calculated as follows: RI=(SUVmax delayed image-SUVmax standard image/SUVmax standard image)*100. Pathological confirmation of residual tumor by histology of the treated lesion was considered as local recurrence. A negative imaging follow-up was considered as complete response. RESULTS: Local recurrence was found in 6/18 lesions, and complete response in the remaining 12. The mean percentage change in SUVmax at 1 month and at 3 months showed a sensitivity and specificity for PET/CT of 50% and 33%, and 67% and 92%, respectively. The RI at 1 month after RFA showed a sensitivity and specificity of 83% and 92%, respectively. CONCLUSIONS: Dual time point PET/CT can predict the outcome at one month after RFA in lung metastases from digestive tract cancers. The RI can be used to indicate the need for further procedures to rule out persistent tumor due to incomplete RFA.

Usefulness of (18)F-FDG PET/CT in recurrent basal cell carcinoma: Report of a case.

We analyze the case of a patient with left periorbital infiltrating basal cell carcinoma treated with surgical excision in October 2010. Surgery included orbital exenteration and reconstruction using skin graft and radiotherapy. In May 2013 a MR imaging showed a mass in the left orbital fossa, suggesting a recurrence in the graft. A basal cell carcinoma recurrence with perineural invasion was confirmed in the biopsy. On (18)F-FDG PET/CT performed, a hypermetabolic activity was observed in the left periorbital area with extension to surrounding sinus and bones. The use of (18)F-FDG PET/CT in patients with advanced basal cell carcinoma has not been fully explored due to the rarity of this entity. This case demonstrates the usefulness of this technique to determine the extent of non-melanocytic recurrent skin tumors, and its value in the staging and treatment control, supporting the incorporation of (18)F-FDG PET/CT in the management of advanced basal cell carcinoma.

[Screening with angiographic images prior to (99m)Tc-HMPAO labelled leukocyte scintigraphy in the diagnosis of periprosthetic infection]. / Cribado mediante angiogammagrafía previo a la realización de gammagrafía con leucocitos (99m)Tc-HMPAO en el diagnóstico de infección de prótesis articulares.

AIM: To evaluate the impact of the angioscintigrapy of the three phase bone scan as screening method to rule out infection of the hip and knee prosthesis prior to performing the (99m)Tc-HMPAO leukocyte scintigraphy. MATERIAL AND METHODS: A total of 120 (70 women, 50 men; mean age 71±11years) with clinical suspicion of hip (n=63) or knee (n=57) infection of the prosthesis and clinical suspicion of infection were evaluated prospectively. All patients underwent three-phase bone scan (angioscintigraphy, vascular and bone phase) and (99m)Tc-HMPAO-labelled white blood cell scintigraphy. Final diagnosis of infection was made by microbiological documentation or clinical follow-up for at least 12months. RESULTS: Eighteen out of 120 patients were diagnosed of infection of hip prosthesis (n=10) or knee prosthesis (n=8). The angioscintigraphy was positive in 15/18 infected cases and in 21/102 of the non-infected cases with a sensitivity of 83%, specificity of 79% and negative predictive value of 97%. Sensitivity and specificity of (99m)Tc-HMPAO leukocyte scintigraphy were 72% and 95%, respectively. If the leukocyte labeled scintigraphies had been used exclusively for patients with positive angioscintigraphy, this would have saved up to 70% of the (99m)Tc-HMPAO leukocyte scintigraphies performed. There were no cases of infection with positive labeled leukocyte scintigraphy and negative angioscintigraphy. CONCLUSION: Angioscintigraphy (blood flow phase of bone scan) is a useful technique for screening for hip and knee joint prosthesis infection, significantly reducing the need for (99m)Tc-HMPAO leukocyte scintigraphy without affecting the sensitivity of the technique.

[Presence of intramammary lymph nodes in the preoperative lymphoscintigraphy to locate the sentinel lymph node. Clinical significance]. / Presencia de ganglios intramamarios en la linfogammagrafía prequirúrgica para localizar el ganglio centinela. Relevancia clínica.

OBJECTIVE: The routes of lymphatic drainage from a breast cancer are the axilla (the most frequent) and the extra axillary regions. Among the latter, there are the so-called intrammamary lymph nodes (IMLN). This study has aimed to assess the incidence of IMLNs in our patients and study the evolution of these cases with IMLN in the lymphoscintigraphy. MATERIAL AND METHODS: Thirty-eight patients (out of 1725) with IMLN in the pre-operative lymphoscintigraphy were assessed. During the surgical procedure, using a gamma probe, IMLNs were located and excised. After their harvesting, a meticulous surgical field scan was performed. When the axillary sentinel node was positive for metastasis, a complete axillary lymphadenectomy was performed. In those where the axillary sentinel node was negative and IMLN was positive (IMLN+), axillary lymphadenectomy was also performed, except for one case. RESULTS: Thirty-four out of the 38 IMLNs were obtained (89.5%), because no lymphatic tissue was found in pathology analysis in three cases (8%) and in one patient (3%) IMLN was not found during surgery. Ten (26%) metastatic IMLNs were located and the remaining 24 IMLNs cases (63%) were metastasis-free. During the clinical follow-up, one patient with IMLN+ developed hepatic metastases. The remaining 33 patients did not present any recurrence. No follow-up data were available for three patients. CONCLUSIONS: IMLN and axillary sentinel node biopsy are recommended when both are depicted in preoperative lymphoscintigraphy. The axilla treatment will only depend on the axillary sentinel node status. Based on the data from other authors and our own experience, avoiding the axillary lymphadenectomy when a metastatic IMLN without axillary involvement seems reasonable.