Differences in regional bone metabolism at the spine and hip: a quantitative study using (18)F-fluoride positron emission tomography

SUMMARY

This study showed that regional bone blood flow and (18)F-fluoride bone plasma clearance measured by positron emission tomography are three times lower at the hip than the lumbar spine.

INTRODUCTION

Measurements of effective bone plasma flow (K (1)), bone plasma clearance (K ( i )) and standardised uptake values (SUV) using (18)F-fluoride positron emission tomography ((18)F-PET) provide a useful means of studying regional bone metabolism at different sites in the skeleton. This study compares the regional (18)F-fluoride kinetics and SUV at the hip and lumbar spine (LS).

METHODS

Twelve healthy postmenopausal women with no history of metabolic bone disease apart from two with untreated osteoporosis were recruited. Each subject underwent 60-min dynamic (18)F-PET scans at the LS and proximal femur two weeks apart. K (1), K ( i ) and SUV were measured at the LS (mean of L(1)-L(4)), femoral neck (FN), total hip (TH) and femoral shaft (FS). Differences between sites were assessed using the nonparametric Kruskal-Wallis test with a Bonferroni correction for multiple comparisons.

RESULTS

Values of K (1), K ( i ) and SUV at the FN, TH and FS were three times lower than at the LS (p = 0.003). Amongst the proximal femur sites, K ( i ) and SUV were lower at the FS compared with the FN and TH, and SUV was lower at the TH compared with the FN (all p < 0.05). The volume of distribution was lower at the TH and FS compared with the LS (p < 0.05).

CONCLUSION

The lower values of K (1), K ( i ) and SUV at the hip suggest that lower bone blood flow in the proximal femur is an important factor explaining the principal reason for the differences in bone fluoride kinetics between the LS and hip sites.

Lymphedema following irradiation in breast cancer: A cross-sectional study

e11569

Background: Nearly 15–30% of breast cancer patients (pts) face lymphedema (LE) following locoregional therapy, incidence being higher with surgery (Sx) & radiotherapy (RT) combination than with Sx alone. We intended to study the incidence of post-RT LE and associated symptoms. Method: We evaluated 104 unilateral breast cancer pts who had completed curative therapy (Sx + RT + chemotherapy ± hormone therapy HT), with a minimum follow up of 6 months. Besides demographic & treatment details, symptoms associated with LE and objective measurements of upper limb circumference were recorded using an indigenous questionnaire. Results: Median age was 45 years (range 28–65). Chest wall or breast RT was delivered using medial & lateral tangential portals (Cobalt-60 unit) in 88 pts & with 12 MeV electrons in 18 pts. Of all pts, 77 were given supraclavicular & axillary RT. HT was given to 72 pts. Pathological stages were: T1/2- 73, T3/4- 27, Tx-4; N0–44, N1–25, N2/3–33, Nx-2. Arm swelling was reported by 68 pts (mild-40, moderate-28). Other symptoms included reduced range of motion (mild-52, moderate-24), fatigue (48), pain (28), numbness (20), infections (12), shoulder droop (12) and local tenderness (8). Forty-four pts reported having psychological stress (mild-40, moderate-4). Nearly 60% had symptoms mandating change in physical activity (mild-56, moderate-8). Dominant hand was involved in 57 pts. Shoulder exercises were advised in 84 pts; compliance was poor in 16, average in 32, & good in 36. Only 36 pts were advised compression garments, compliance being poor in 28, average in 4 & good in 4. Objective measurements revealed a difference of ≥3 cm in 27 pts in mid-arm circumference (MAC) (median 5.5 cm, maximum 8 cm) & 34 pts in forearm circumference (FAC) (median 3.5, maximum 7 cm). There was no significant association between MAC or FAC with age, stage, body surface area, basal metabolic index, Sx type, chemotherapy or HT. Perceived LE and objective measurements correlated well. MAC difference >3 cm was seen in 28.5% (22/77) pts who received axillary RT and in 18.5% (5/27) of those who received only local RT. Conclusions: LE, with its associated complications, is often understudied in breast cancer survivors. Revision of Sx and RT policies (e.g., omission of axillary dissection & RT in selected pts) may help minimise LE.

No significant financial relationships to disclose.

Long-term clinical remission following radiotherapy in tracheal adenocarcinoma: review of the published work

A 55-year-old man with tracheal adenocarcinoma presented with difficulty in breathing and cough with blood-tinged expectoration. As the patient refused surgery, he was treated with definitive radiotherapy to the neck and superior mediastinum to a total dose of 50 Gy (initially 40 Gy by AP/PA portals followed by 10 Gy with a three-field technique). He showed significant symptomatic relief to radiotherapy and defaulted from further treatment. He remained asymptomatic for 7 years, following which he developed sternal metastases and a local tumour recurrence. This case illustrates that long-term clinical remission can be achieved by radiotherapy alone in this rare histological subtype of tracheal carcinoma.

Postoperative radiotherapy in head and neck squamous cell cancers: AIIMS experience

16514

Background: Squamous cell cancers of the head and neck are one of the most common malignancies in India. Most patients present in advanced stages of disease. Postoperative radiotherapy is generally an integral part of management in these patients. Methods: Patients of head and neck squamous cell cancers treated with surgery and postoperative radiotherapy at AIIMS between January 1999 to December 2004 were retrospectively analyzed. Results: A total of 386 patients were treated of which 281 were available for evaluation. There were 233 males and 48 females. Median age was 46 years (range 18–73). Site-wise distribution was: oral cavity- 202, larynx-55, hypopharynx-14, paranasal sinus-4, oropharynx-4, neck nodes with unknown primary-2. Post-surgical margins were adequate in 241, close in 5 (2%) and positive in 35 (12%). Pathological stage grouping was: Stage I- 11(4%), Stage II- 52 (18%), Stage III- 63(22%), Stage IV- 155 (55%). Neck node dissection was done in 245 patients and nodes were pathologically negative in 119 (42%). Extracapsular extension (ECE) was seen in 19(7%) patients. Bone/cartilage invasion was seen in 62(22%). Patients with high risk features (close/positive margins, ECE, 4/> positive nodes) were prescribed a dose of 64 Gy while the rest were planned to receive 60 Gy. 85% of patients completed the intended course of radiation. At a median follow up of 37 months, local recurrences were seen in 28 (10%), regional recurrence in 25 (9%) and distant metastasis in 10 (4%) patients. A second malignant neoplasm occurred in 6 patients (3-oropharynx, 2-oral cavity, 1-lung). Disease free survival (DFS) was 68%. ECE, post-surgical margin status and pathological lymph node status were significantly associated with DFS. Duration of postoperative radiotherapy and the surgery to radiotherapy interval did not significantly affect DFS. Conclusions: ECE, postsurgical margin status and pathological lymph node status significantly impact DFS in patients of surgically treated squamous cell cancers of head and neck. These patients require doses of adjuvant radiation >/=64 Gy.

No significant financial relationships to disclose.

Extensive bone metastases from basal cell carcinoma of the eye

The incidence of metastases from basal cell carcinoma is rare. We report a 66-year-old woman who had basal cell carcinoma of the outer canthus of the left eye. Six months following radical radiotherapy, she developed local recurrence for which an orbital exenteration was done. Four months later, she developed rapidly-progressive multiple skeletal metastases and died soon after.

Infiltrating ductal carcinoma of male breast: A retrospective study

10753

Background: A single-institution retrospective review of the clinical presentation, treatment and outcome of male breast infiltrating ductal carcinoma (IDC). Methods: Case records of 25 male patients with a histological diagnosis of infiltrating ductal carcinoma (IDC) of breast who were treated in a single institution between 1997 to 2004 were retrospectively reviewed. Results: Patients presented at a mean age of 56 years (range, 34 to 80 years). The presenting complaint was a painless lump in the breast in all the cases. The right breast was involved in 13 cases (52%). There were no cases of bilateral breast cancer. The distribution of patients by stage at presentation are: stage IIA (24%), IIB (20%), IIIA (8%), IIIB (40%), and IV (8%). None of the patients presented with stage I disease. One patient had lung metastases at presentation. Rest of the 24 patients (96%) underwent surgery (modified radical mastectomy, 22 patients; simple mastectomy, 2 patients). Fifteen patients (60%) received adjuvant local radiotherapy. All patients received adjuvant chemotherapy: As per departmental protocol, those presenting before 2000 were treated using a regimen of Cyclophosphamide, Adriamycin and 5-Fluorouracil. After 2000, Ebirubicin was substituted for Adriamycin. Three patients were further administered Docetaxel, the indication being disease progression after first line adjuvant chemotherapy. Estrogen & Progesterone receptor positivity was 64% and 60% respectively. Hormonal therapy (Tamoxifen 14 patients, Anastrozole 2 patients) was administered in these patients. The length of follow-up from time of presentation ranged from 4 to 100 months (mean, 28 months; median, 13 months). At the time of analysis, of the 25 patients, 18 patients (72%) remain disease free, whereas 7 patients (28%) developed progressive disease. Median survival was not reached at the present time. Conclusions: Breast cancer, specifically IDC tends to present at a later stage in males, due to a lack of screening for the disease. In the present series, as a result of the advanced stage of initial presentation, all patients received adjuvant chemotherapy. There is a need to improve awareness among males, of the possibility of a painless breast lump being the first symptom of an underlying malignancy.

No significant financial relationships to disclose.

Ca2+ current enhancement by alpha 2/delta and beta subunits in Xenopus oocytes: contribution of changes in channel gating and alpha 1 protein level

1. A combined biochemical and electrophysiological approach was used to determine the mechanism by which the auxiliary subunits of Ca2+ channel enhance the macroscopic Ca2+ currents. Xenopus oocytes were injected with RNA of the main pore-forming subunit (cardiac: alpha 1C), and various combinations of RNAs of the auxiliary subunits (alpha 2/delta and beta 2A). 2. The single channel open probability (Po; measured at 0 mV) was increased approximately 3-, approximately 8- and approximately 35-fold by alpha 2/delta, beta 2A and alpha 2/delta+beta 2A, respectively. The whole-cell Ca2+ channel current was increased approximately 8- to 10-fold by either alpha 2/delta or beta 2A, and synergistically > 100-fold by alpha 2/delta+beta 2A. The amount of 35S-labelled alpha 1 protein in the plasma membrane was not changed by coexpression of beta 2A, but was tripled by coexpression of alpha 2/delta (either with or without beta). 3. We conclude that the increase in macroscopic current by alpha 2/delta is equally due to changes in amount of alpha 1 in the plasma membrane and an increase in Po, whereas all of the effect of beta 2A is due to an increase in Po. The synergy between alpha 2/delta and beta in increasing the macroscopic current is due mainly to synergistic changes in channel gating.

Formic acid solvent system. II. Conductance and solvation studies of 1 : 1 electrolytes in formic acid

Conductances of some 1 : 1 electrolytes have been measured in the concentration range (5-100) x 10-3 mol l-1 in anhydrous formic acid at 25�. The conductance data have been analysed by Fuoss-Shedlovsky equations. Transference numbers of sodium and potassium formates have been measured in this solvent at 25� by a modified Hittorf's method in the concentration range (3-80) x mol l-1. Ionic mobilities, effective ionic radii and solvation numbers of various ions in solution have been calculated. Solvation of cations decreases with the increase in the crystal radii of the ions.