Bernardo Leão Spiro

Sentinel lymph node procedure in patients with epidermoid carcinoma of the anal canal: early experience.

PURPOSE This study was conducted to assess the feasibility of the sentinel lymph node procedure in patients with epidermoid carcinoma of the anal canal. METHODS Between February 2001 and November 2002, 14 patients with epidermoid carcinoma of the anal canal and no clinical evidence of inguinal involvement were prospectively enrolled in the study. The sentinel lymph node procedure consisted of a combination of preoperative lymphoscintigraphy with technetium 99m dextran 500 injected around the tumor and intraoperative detection of the sentinel node with a gamma probe. Patent blue V dye was also injected at the periphery of the tumor to facilitate direct identification of the blue-stained lymph node. After removal, the sentinel node was studied by hematoxylin and eosin staining and immunohistochemistry for pancytokeratins (antigen A1 and A3). RESULTS Detection and removal of sentinel lymph nodes was possible in all patients. There was no correlation between tumor size and pattern of lymphatic drainage to the groin. Tumors located in the midline of the anal canal gave rise to bilateral sentinel nodes in eight of nine cases. In total, 23 sentinel lymph nodes were removed. One patient (7.1 percent) had a node identified as positive for metastatic carcinoma on immunohistochemical staining. Surgical complications were minimal. CONCLUSIONS The standardized technique was safe and highly effective in sampling inguinal sentinel lymph nodes in carcinoma of the anal canal. It also proved to be useful as an instrument to detect micrometastatic deposits in clinically normal nodes. Our early results suggest the sentinel lymph node procedure may have a role in guiding a more selective approach for patients with anal cancer. Additional studies in a larger patient population to determine the sensitivity and specificity of this method are warranted.

Sentinel Lymph Node Procedure in Patients With Epidermoid Carcinoma of the Anal Canal

AbstractPURPOSE: This study was conducted to assess the feasibility of the sentinel lymph node procedure in patients with epidermoid carcinoma of the anal canal. METHODS: Between February 2001 and November 2002, 14 patients with epidermoid carcinoma of the anal canal and no clinical evidence of inguinal involvement were prospectively enrolled in the study. The sentinel lymph node procedure consisted of a combination of preoperative lymphoscintigraphy with technetium 99m dextran 500 injected around the tumor and intraoperative detection of the sentinel node with a gamma probe. Patent blue V dye was also injected at the periphery of the tumor to facilitate direct identification of the blue-stained lymph node. After removal, the sentinel node was studied by hematoxylin and eosin staining and immunohistochemistry for pancytokeratins (antigen A1 and A3). RESULTS: Detection and removal of sentinel lymph nodes was possible in all patients. There was no correlation between tumor size and pattern of lymphatic drainage to the groin. Tumors located in the midline of the anal canal gave rise to bilateral sentinel nodes in eight of nine cases. In total, 23 sentinel lymph nodes were removed. One patient (7.1 percent) had a node identified as positive for metastatic carcinoma on immunohistochemical staining. Surgical complications were minimal. CONCLUSIONS: The standardized technique was safe and highly effective in sampling inguinal sentinel lymph nodes in carcinoma of the anal canal. It also proved to be useful as an instrument to detect micrometastatic deposits in clinically normal nodes. Our early results suggest the sentinel lymph node procedure may have a role in guiding a more selective approach for patients with anal cancer. Additional studies in a larger patient population to determine the sensitivity and specificity of this method are warranted.

Sentinel lymph node identification and sampling in women with early breast cancer using 99mTc labelled dextran 500 and patent blue V dye

The status of the homolateral axillary lymph nodes is still the most important prognostic factor in early stage breast cancer. The information obtained from the pathological examination of the lymph nodes guides is of critical importance in the decision process regarding the use of postoperative adjuvant therapy. However, lymph node axillary dissection can be followed by significant locoregional morbidity. The sentinel lymph node (SLN) technique was developed as a means of avoiding the full exploration of the axilla and consists in the identification of the first lymph node in the lymphatic drainage system of the breast tumour in the homolateral axilla. It has been demonstrated that the status of the SLN is highly predictive for the presence or absence of tumour involvement in the remaining lymph nodes in the axilla. In this study we evaluated the SLN technique using both 99mTc labelled dextran 500 and patent blue V dye in relation to the classical lymph node resection a series of 56 women with early breast cancer who attended the Breast Unit of the Academic Hospital of the Federal University of Rio Grande do Sul, Brazil. To our knowledge this is the first report in the literature of the utilization of 99mTc dextran 500 for the SLN technique. As there are no similar commercially available dedicated radiopharmaceuticals labelled for use in lymphoscintigraphy studies, we report on an effective method to label dextran 500 with 99mTc which proved to be simple, inexpensive and yielded similar results for SLN identification compared with those given in the literature. The median age of the patients was 57 years (range 32-82 years). Seventeen patients were age 50 years or less, and 39 patients were older than 50 years. The median tumour size was 2.0 cm (range 0.8-7.0 cm). The mapping of the SLN was possible in all cases during the transoperative period by using a hand-guided gamma probe and a blue dye. A median of 2.0 (range 1-5) SLN were excised per patient. The median of axillary lymph nodes excised per patient was 21 (range 10-36). The calculated sensitivity and specificity of the method were 95.6% and 100%, respectively. The negative predictive value and overall accuracy were 97% and 98.2%, respectively. In conclusion, the SLN technique was feasible and produced similar positive results as previously reported in the literature.

Scintigraphic sentinel node detection in breast cancer patients : paired and blinded comparison of 99mTc dextran 500 and 99mTc phytate

BackgroundBreast cancer surgery has evolved towards minimizing morbidity, maximizing cure rates and stratifying treatments according to disease stage. Sentinel lymph node biopsy is becoming standard practice in most centres. However, no standard radiopharmaceutical exists. ObjectivesTo blindly compare 99mTc dextran 500 and 99mTc phytate in the scintigraphic detection of sentinel lymph nodes. Endpoints were the detection of axillary or internal mammary lymph nodes, number of lymph nodes detected, detectability in the first versus the second hour of evaluation and the relationship between rate of detection and age or body mass index. MethodsForty-six patients with histological diagnosis of early breast cancer, without previous surgical treatment, were enrolled in our study. Each patient underwent lymphoscintigraphy twice: on one day with 99mTc dextran 500 and on another day with 99mTc phytate. Images were acquired 1 h and 2 h after tracer administration. ResultsEighty-eight lymphoscintigraphic studies were performed in 44 patients. On the first image (taken at 1 h), 34 patients from the 99mTc dextran group showed sentinel nodes compared with 28 positive examinations using 99mTc phytate (P=0.113). On the second image (taken at 2 h) 39 patients from the 99mTc dextran group showed positive results compared to 30 positive examinations using 99mTc phytate (P=0.036). There was no statistically significant correlation between the body mass index or age and the result of the lymphoscintigraphy. Conclusion99mTc dextran 500 is better than 99mTc phytate for use in a 2 h interval scintigraphic protocol because it demonstrates the sentinel node in a significantly higher number of patients and also showed more lymph nodes suitable for pathological examination.

Long-term survival data on sentinel lymph node biopsy in anorectal melanoma

Sentinel lymph node (SLN) biopsy is currently the method of choice to assess the nodal status of patients with cutaneous melanoma. It has largely replaced elective lymph node dissection, sparing patients with negative SLN the morbidity associated with a complete regional lymphadenectomy. However, experience with the SLN procedure in anal melanoma has been limited to a few reported cases, probably due to the rarity of this tumor. Anorectal melanoma (AM) accounts for 1% of all anorectal malignancies. Most patients are diagnosed with advanced disease and have poor 5-year survival (0–22%). Although surgery is the mainstay of treatment, there appears to be no difference in survival whether wide local excision (LE) or abdominoperineal resection is performed. Locoregional metastases are frequent and may involve both inguinal and pelvic lymph nodes [1]. In this letter, we report a case of AM that had an unexpectedly favorable clinical evolution. Our patient was an 89-year-old diabetic woman presenting with an anal lesion that she first noticed 8 months earlier. It was a non-pigmented nodule, 3 cm in diameter, located at the dentate line. Inguinal palpation was unremarkable. Biopsy of the lesion showed an undifferentiated tumor, but the immunohistochemical analysis was positive for S-100 protein and HMB-45, thus establishing the diagnosis of AM. Staging workup did not detect metastases. Considering the general condition of the patient, treatment by wide local excision of the tumor along with SLN biopsy was proposed. Twelve hours before surgery, Dextran 500 labeled with Technetium-99 m was injected into the parenchyma around the primary tumor. Subsequently, lymphoscintigraphy demonstrated a SLN (hot spot) in the right groin (Fig. 1). On the following day, patent blue dye was injected at the same sites around the tumor. The inguinal area was scanned with a gamma probe, and a 3-cm incision was made over the hot spot. During inguinal dissection, the blue color of the SLN served as a guide to its location. After removal of the SLN, excision of the AM was performed. Histopathology and immunohistochemistry of the surgical specimen confirmed AM with tumor-free resection margins. The SLN was diagnosed as positive for metastatic melanoma. The patient refused any additional treatment but remained free of disease after 52 months of follow-up. Although the SLN procedure has been successfully tested in other anal tumors, the investigation into the SLN in AM is currently limited to 6 cases [1–4]. Long-term survival was not documented in any of them. In our patient, we used the same SLN procedure we had previously investigated in cases of epidermoid carcinoma of the anal canal and rectal adenocarcinomas invading the dentate line [5, 6]. Our technique, which consisted of a combination of blue dye and radio-colloid, was effective in sampling a SLN from the left inguinal area. Moreover, it allowed the detection of metastatic deposits within the SLN, which D. C. Damin (&) M. A. Rosito Division of Coloproctology, Hospital de Clinicas de Porto Alegre (Sala 600) and Department of Surgery, Federal University of Rio Grande do Sul, Rua Ramiro Barcelos 2350, 90035 903 Porto Alegre, RS, Brazil e-mail: damin@terra.com.br

Continuous positive airway pressure and body position alter lung clearance of the radiopharmaceutical 99mtechnetium-diethylenetriaminepentaacetic acid (99mTc-DTPA)

The purpose of this investigation was to evaluate the pulmonary clearance rate of 99m technetium-diethylenetriaminepentaacetic acid ( 99m Tc-DTPA) through the use of continuous positive airway pressure (CPAP) in different postures. It was a quasi-experimental study involving 36 healthy individuals with normal spirometry. 99m Tc-DTPA, as aerosol, was nebulized for 3 min with the individual in a sitting position. The pulmonary clearance rate was assessed through pulmonary scintigraphy under spontaneous breathing and under 20 and 10 cmH 2 O CPAP in the sitting and supine positions. The clearance rate was expressed as the half-time (T 1/2 ), that is, the time for the activity to decrease to 50% of the peak value. 20 cmH 2 O CPAP produced significant reduction of the T 1/2 of 99m Tc-DTPA in the supine position (P = 0.009) and in the sitting position (P = 0.005). However, 10 cmH 2 O CPAP did not alter the T 1/2 of DTPA in both positions. The postural variation from supine to the sitting position with 10 cmH 2 O CPAP (P = 0.01) and 20 cmH 2 O (P = 0.02) also reduced the T 1/2 of 99m Tc-DTPA. High levels of positive pressure in normal lungs resulted in faster 99m Tc-DTPA clearance. Moreover, the sitting position further increased the clearance rate of the 99mTc radioaerosol imaging in the two pressure levels studied. Key words: Continuous positive airway pressure, 99m Tc-DTPA, scintigraphy, posture.

Perfused lung volume to thoracic gas volume ratio (perfused lung fraction) in patients with COPD and in controls.

BackgroundThe deterioration of the ventilation-to-perfusion distribution in patients with chronic obstructive pulmonary disease (COPD) reflects structural changes affecting both the airways and the blood vessels. These changes result in lung perfusion abnormalities that may be quantified by lung perfusion single photon emission computed tomography (SPECT). ObjectiveTo compare the perfused lung fraction (PLF) in patients with airflow obstruction and controls. MethodsFourteen patients with COPD and 21 controls underwent spirometry, whole-body plethysmography, and lung perfusion SPECT. PLF was derived from the ratio of perfused lung volume (measured by SPECT) to thoracic gas volume (measured by whole-body plethysmography). ResultsIn the whole study sample, there were 18 (51%) women and 17 (49%) men, mean age was 46.2 (±20.3) years, range: 18–80 years). In the COPD group, PLF was 0.74 (±0.08), whereas in the control group PLF was 0.99 (±0.18) (P<0.001). PLF correlated directly with forced expiratory volume in 1 s to forced vital capacity (r=0.597, P<0.001). Perfused lung volume was 3.66 (±0.64) l in the COPD group compared with 2.71 (±0.70) l in the control group (P<0.001). ConclusionThe fraction of lung volume receiving blood from the pulmonary artery is reduced in patients with COPD. The degree of underperfusion seems to correlate with the degree of airflow limitation.

Unusual excretion of Tc-99m MDP in regional intestinal lymphangiectasia.

A patient with intestinal lymphangiectasia was previously found to have, on Tc-99m dextran lymphoscintigraphy, dilatation of the lymphatics in the distal ileum and ascending colon. Tc-99m MDP imaging showed findings consistent with stress fractures in the left and right fifth metatarsals and sites associated with intestinal lymphangiectasia.

Intraoperative injection of technetium-99m-dextran 500 for the identification of sentinel lymph node in breast cancer

PURPOSE to determine the efficacy of intraoperative injection of Dextran-500-99m-technetium (Tc) for the identification of the sentinel lymph node (SLN) in breast cancer and analyze time to label the SLN in the axillary region. METHODS a prospective study between April 2008 and June 2009, which included 74 sentinel lymph node biopsies (SLNB) in patients with breast cancer in stages T1N0 and T2N0. After induction of anesthesia, 0.5 to 1.5 mCi of Dextran-500-99m-Tc filtered 0.22 µm in a volume of 5 mL was injected intraoperative using the subareolar technique for SLNB. After labeling with the radioisotope, 2 mL of patent blue was injected. The time elapsed between injection and the axillary hot spot, the in vivo and ex vivo counts of the hottest nodes, the background count, and the number of SLN identified were documented. Data were analyzed using descriptive statistics with SPSS program, version 18. RESULTS we identified the SLN in 100% of cases. The rate of SLN identification with the probe was 98% (73/74 cases). In one case (1.35%) the SLN was labeled only with the blue dye. The mean dose of radioisotope injected was 0.97 ± 0.22 mCi. The average time to label the SLN was 10.7 minutes (± 5.7 min). We identified on average of 1.66 SLN labeled with the radioisotope. CONCLUSION the procedure for SLN identification with an intraoperative injection of the radioisotope is oncologically safe and comfortable for the patient, providing agility to the surgical team.

Comparação da linfocintilografia com dextrano 500 com a do fitato na pesquisa do linfonodo sentinela no câncer de mama

OBJETIVO: comparar a acuracia de dois radiocoloides na marcacao do linfonodo sentinela (LNS) por imagem. METODOS: as pacientes foram incluidas no periodo de maio de 2002 a abril de 2004. Neste estudo duplo-cego, a paciente foi submetida duas vezes ao mesmo exame, mas com farmacos diferentes, sendo que os farmacos, tecnecio-99m-dextrano 500 (dextrano) e tecnecio-99m-fitato (fitato), foram injetados, na mama, em quatro pontos na area peritumoral e no subcutâneo superficialmente ao tumor, com volume de 2 ml, contendo de 1,0 a 1,5 mCi, em aliquotas de 0,4 ml. Para a obtencao das imagens, duas horas apos a injecao do radiofarmaco, usamos gama-câmera com colimador de alta resolucao. A drenagem linfatica axilar foi identificada em imagens radiograficas estaticas, anterior e lateral. A estatistica para pares discordantes foi realizada pelo teste de MacNemar e pelo teste Z para proporcoes. RESULTADOS: na analise das 40 pacientes, obtiveram-se 15 pares com imagens positivas iguais, 4 pares com imagens negativas e 21 pares com imagens distintas, seja porque uma era negativa, seja porque o numero de LNS marcados era diferente. A analise do desempenho quanto ao sucesso e insucesso mostrou 35 e 27 imagens positivas e 5 e 13 imagens negativas, respectivamente para o dextrano e o fitato, sendo que das negativas 4 eram comuns. O estudo estatistico pelo teste de MacNemar mostrou p=0,026, com odds ratio (OR) = 0,11 e IC 95% 0,01<OR<0,85. A taxa de sucesso foi 67,5% para o fitato e 87,5% para o dextrano 500 e a avaliacao da acuracia pelos percentuais tambem foi significante, com p=0,032. Pela ANOVA o numero de LNS apontados, foi altamente significante, com p=0,008. CONCLUSAO: este estudo demonstra que a linfocintilografia com dextrano 500 indica linfonodos com mais frequencia que o fitato, quando usados com a mesma metodologia, na obtencao da imagem do LNS de tumores da mama.